European Palaeobotany and Palynology Conference 2026

The plant fossil record is, by its very nature, fragmentary, but some pieces of this puzzle preserve morphological and/or anatomical characters that provide direct insights into the ecology and physiology of extinct taxa. This "functional approach" allows paleobotanists to study plant evolution in a way that complements systematics, seeing fossil plants as once-living organisms that interacted with their environment. For example, a fossil trunk with a thick bark or evidence of new shoots produced from dormant buds suggest an ability to withstand stressful conditions. Interactions with other organisms can also be documented from isolated plant fossils, sometimes in great detail. This approach is also relevant for reconstructing functional traits at the level of a single organ or tissue. The distribution of tissues within a stem can be translated into mechanical properties. Fossil wood anatomy enables us to estimate its hydraulic properties and even to detect fine physiological processes such as tylosis formation. While such functional traits directly impact plant growth and survival, their documentation in the fossil record remains patchy due, in part, to our dependence on exceptional preservation. I will present advances made over the last 20 years in our understanding of the biology of two emblematic Paleozoic trees: (1) Archaeopteris, one of the earliest arborescent taxa and a major component of Late Devonian floras, and (2) Glossopteris, which dominated most Permian floras of Gondwana. I will also discuss how we can move forward our investigations of fossil plant biology and encourage its integration into future (paleo)botanical research.

The greatest diversity losses in Earth’s history occurred at the end of the Paleozoic Era, during the end-Permian extinction event (EPE). For life on land, plants are unparalleled archivists of the EPE, preserving evidence of ecosystem dynamics, biodiversity and biogeography changes, climatic instability, and carbon cycle (dys)function.

The EPE is characterized by the largest climate-state change of any mass extinction event, transitioning from coolhouse to hothouse, driven by massive and rapid greenhouse gas emissions. However, it is not yet clear how much influence other stressors (e.g., UV-B, phytotoxic metals) may have played in the downfall of terrestrial ecosystems.

This presentation will propose a simple hypothesis: greenhouse gas-driven climatic changes played the central role in the EPE. If this hypothesis is correct, and since most mass extinction events share a similar underlying cause, they can be placed on a spectrum of severity with the EPE as the worst-case scenario. While the timing and severity of each hyperthermal event are unique, the EPE could offer a standardized yardstick against which other events can be compared.

As the tempo and magnitude of these changes are being revealed, the relevance of the EPE to our presently warming world is becoming more relevant. Deep-time records offer our only observational window into ecosystem responses of greenhouse gas-driven climate changes over the longest-possible timescales. While the EPE represents climatic change beyond all IPCC future climate scenarios, it may presage longer-term forecasts, if our species doesn’t take drastic preventative action.

Direct evidence of animal–flower interactions in the fossil record is rare, but pollen preserved on or inside fossil animals provides unique insight into the evolution of pollination systems through time. In recent years, there has been accumulating evidence of flower visitation from the Cenozoic fossil record, and fossil flies, beetles, bees, birds, and bats bearing pollen have been discovered. Using fluorescence stereomicroscopy, micro-invasive sampling, and combined light, scanning electron, and transmission electron microscopy, fossil pollen extracted from animals and flowers has been identified with high taxonomic precision, allowing detailed reconstruction of Cenozoic pollination networks. The fossil record of direct bee-mediated pollination now extends back to the Paleocene (Selandian–Thanetian, 61.6–56 Ma) of Menat, France, representing the oldest known evidence of pollen transport by bees. Bee taxa including Probombus, Tithonanthidium, and Megachilinae carried pollen from Fabaceae, Fagaceae, Euphorbiaceae, Rutaceae, Cornaceae, Saururaceae, Nyssaceae, and Sapotaceae, indicating broad floral exploitation already during the Paleocene. The presence of Fabaceae pollen on multiple bee taxa suggests that legumes represented an important early floral resource. The Menat assemblage differs markedly from younger Eocene to Miocene biotas of Europe in both bee diversity and pollen composition. Middle Eocene assemblages from Messel and Eckfeld, Germany, preserve diverse bee–plant associations involving Araliaceae, Tilioideae, Euphorbiaceae, Nyssaceae, Elaeocarpaceae, Iridaceae, Olacaceae, Juglandaceae, and Sapotaceae. Recurrent associations, such as Araliaceae and Tilioideae pollen on several bee taxa (Electrapis, Protobombus), imply long-term continuity or widespread abundance of particular floral resources, whereas unique pollen occurrences may indicate more specialized interactions.

This keynote addresses the changing reality of palynology and palaeobotany through a historical lens. Drawing on examples from conference records, institutional structures, and personal accounts from the 1900s onward, it highlights a period in which both fields flourished. In contrast, the present landscape is increasingly characterised by fragmentation, specialisation, and reduced representation within individual departments. Patterns we all recognise as potential drivers of extinction.

Rather than framing this development solely as decline, the talk examines it as a form of disciplinary turnover, raising the question of whether current trends reflect natural evolution or signal a more critical tipping point. Particular emphasis is placed on the role of scientific context and historical awareness in interpreting both past and present research. Perhaps the understanding of the intellectual and socio-economic history of a field and its authors can contribute and inform its future development.

The keynote explores the importance of conferences and professional exchange as spaces where fragmented expertise can be reconnected. In an environment where individual researchers often represent narrow niches, these interactions become central to provide inspiration, knowledge transfer, and collective identity. Combining historical reflection with contemporary observations, the talk aims to provide a framework for thinking about continuity, adaptation, and resilience in palynology and palaeobotany.

During the Devonian, the two largest groups of euphyllophytes, the lignophytes and the ferns s.l., converged independently toward similar stele shapes (i.e., the architecture of primary vascular tissues). Throughout this period, stelar architecure in these groups evolved from ancestors with simple protosteles into a range of diversity that includes most of the stele types present in modern plants, as well as unique stele shapes not seen in modern tracheophytes. This early and broad diversification, the extant and extinct diversity of stelar architecture, as well as the architectural convergence observed across phylogenetically distant lineages, inspire questions about the potential selective advantage of different stele types. However, despite decades of research on this subject, the adaptive value of stele morphology is still debated. The two prevailing hypotheses propose either (1) that stele architecture is adaptive and has evolved under selection towards increased drought resistance, or (2) that stele shapes are non-adaptive byproducts - evolutionary spandrels - of developmental integration. We focus on the initial results of a project aimed at testing which of the two hypotheses best explains the evolution and diversity of stele shapes by developing a model capable of reproducing the entire range of stele diversity observed across vascular plants. In subsequent steps we plan to simulate the evolutionary trajectory of stele shape in the absence of selective pressures and under selection driven by drought resistance. The results of simulations will be compared against the diversity of Devonian stelar architectures and their distribution across known phylogenetic relationships of Devonian groups.

The Early Devonian Rhynie chert is one of the most exceptional fossil archives known for exquisitely preserved plants, microbes and animals. These fossils with cellular-scale structures have provided unique insights into early terrestrial life. The Rhynie animal assemblage is composed of various arthropods, including hexapods, myriapods and arachnids, implying a complex faunal structure and ecosystem. Although many of the arthropods are well described through the investigation of classical thin sections, we possess less information about their 3D morphology, especially of larger individuals, as fossils remain hidden within the solid chert matrix and are often destroyed when making thin sections. This is a critical limitation for understanding their 3D form and ecology. Here we present the entire 3D reconstructions and high-density community of Palaeocharinus, millimetre-sized principal predators in the Rhynie ecosystem, via the Digital Fossil Mining system. Their large lateral eyes, with anterior elevation, suggest wide frontal fields of view, and their raptorial chelicerae, movable from downwards to forwards, were likely useful for capturing and holding prey during pre-oral digestion. The sedimentary facies and mode of occurrence indicate that the featured chert block preserves Palaeocharinus and plenty of surrounding plants in situ, and that their annual population was high. These findings show that the Rhynie environment, one of the earliest land ecosystems, was covered by a 'tiny forest' of centimetre-sized plants capable of sustaining abundant adaptive predators.

The historical locality of Bjørnøya (Bear Island, Svalbard) yields one of the few known uppermost Famennian (~360 Ma) terrestrial floras, originally documented by pioneering paleobotanists A.G. Nathorst and H.J. Schweitzer. A forthcoming summer 2026 expedition aims to provide a comprehensive geological context for these plant-bearing strata, integrating high-resolution sedimentology and paleoecological analyses to reconstruct the architecture of these latest Devonian communities. Based on historical collections and new material, rhacophytalean ferns from Bjørnøya are re-evaluated using modern morphological insights to clarify the complex morphology and architectural development of Cephalopteris mirabilis. Initial co-occurrence and quadrat-based analyses suggest an ecological partitioning similar to the Catskill Formation (USA), where distinct lineages dominated specific microhabitats. The latest Famennian landscapes comprised lycopsid forests surrounding oxbow lakes and stands of arborescent sphenopsids assigned to Pseudobornia ursina. Understory vegetation was specialized on these water-saturated soils, consisting primarily of an undescribed seed plant morphotype. Concurrently, alluvial floodplains adjacent to these mires were heavily dominated by the scrambling, spiny rhacophytalean C. keilhaui. This fieldwork provides critical macrofossil compression material to propose comprehensive whole-plant concepts. Ultimately, this research offers a detailed reconstruction of the paleotropical vegetational shifts that occurred during a pivotal evolutionary window. This key period saw the rapid radiation of ferns, early seed plants, and arborescent lycopsids, providing a crucial evolutionary bridge toward the iconic Carboniferous coal swamp ecosystems.

Each organism possesses a unique chemical “fingerprint” known as the elementome, shaped by evolutionary history, mineral availability, and plant function. Portable XRF analysers have recently been used to study the elementomes of herbarium specimens and identify hyperaccumulator species, but this approach has not yet been widely applied to plant fossils. Here, we demonstrates that the palaeo-elementome reflects ecological changes associated with the Mid–Late Pennsylvanian Boundary (MLPB) turnover event. Fossils predating the MLPB contain higher concentrations of iron (Fe), aluminium (Al), and potassium (K), whereas post-boundary specimens are enriched in titanium (Ti), niobium (Nb), and zinc (Zn). Principal components analysis revealed a stronger chemical distinction between pre- and post-boundary fossil plants than between their surrounding sediment matrices, indicating that these chemical patterns are not solely the result of diagenesis or sediment chemistry. Instead, the palaeo-elementome likely preserves aspects of original plant biology, including functional traits and plant–environment interactions. These findings establish the palaeo-elementome as a promising new proxy for investigating plant functional traits in deep time. Further development of this approach could improve understanding of nutrient use, plant function, and vegetation responses to environmental change and crisis events in deep time, while also contributing to broader research on fossilization and diagenetic processes.

Plant-insect interactions form the basis of virtually all modern terrestrial trophic networks. However, when and how this modernisation occurred remains unclear. Following the origin of herbivory during the Devonian, minimal levels of plant consumption have been reported in late Palaeozoic studies. From this, it has been hypothesised that during the Middle Pennsylvanian (late Carboniferous), detritivory was the dominant feeding strategy in Euramerican floras. The diversification of herbivorous species did not occur until the Late Pennsylvanian period, coinciding with the comprehensive expansion and solidification of contemporary trophic networks during the Early Permian epoch. In this communication, we challenge this view with the quantification of herbivory damage on the ecosystem of Nord-Pas-de-Calais (France). Through the study of the associational record on Medullosales, we assess the diversity and intensity of plant damage through time (Early-Middle Pennsylvanian). This pteridosperm group is a key component of the Carboniferous wetland biome, covering a wide array of ecological niches, proving to be a good indicator of trophic network complexity. Total plant damage from 4133 fossil specimens was evaluated, recording 703 feeding events belonging to 65 damage types, which covers all modern feeding strategies except mining. Significantly, results reveal that neither herbivory diversity not intensity is greatly affected by total Medullosales richness; however, together with Medullosales abundance, plant damage seems to be influenced by the rise and fall of glacial phases. This highlights the sensitivity of plant-arthropod interactions to global environmental changes, even at its early stages of development.

Digital Fossil Mining (DFM) is a new technique established by one of us (YI) that enables all fossils and other inclusions within a rock to be recorded as high-resolution tomographic images in a fully digitized form. The method has already produced significant results, including the discovery and reconstruction of marine organisms and terrestrial plants preserved in Cretaceous calcareous concretions. The Rhynie Chert is an ideal material for the application of DFM, and here we report some initial results, together with its future potential. Two chert blocks have been subjected to serial grinding and imaging. One represents a peaty soil and contains accumulated plant remains, several types of sporangia, and fungi. The second is a large block that preserves plants growing on peat during a series of depositional events, documenting their progressive burial by repeated influxes of sediment. These data have made it possible to obtain an integrated view of changes in species composition, life histories, and ecosystem structure among plant communities influenced by continual sediment accumulation. For individual plants, we have succeeded for the first time in reconstructing their original 3D forms and have clarified certain morphological features previously less understood. Research on associated organisms, including arthropods and fungi, is also progressing. DFM can address a wide range of questions spanning from biology to earth sciences and has opened new directions for Rhynie Chert research. In addition, the resulting visualized digital environment has considerable potential for educational use in museums and other public settings.

Silica sinters deposited by hot-spring activity form Lagerstätten with abundant three-dimensional, cell-preserved fossils, as exemplified by the Rhynie chert. Palaeoecological interpretations of fossil sinters have drawn on modern large-scale geothermal provinces to infer their environmental settings and formation processes. Well-documented modern examples of silica sinters recording persistent terrestrial vegetation around hot-spring systems remain limited. Here, we present a new depositional facies model of silica sinter from a forested island-arc setting in Japan. We describe the preservation of present-day forest vegetation that coexists with ongoing sinter deposition. At Nakabusa Hot Springs in central Japan, thermal waters gently emerge from numerous small seeps on densely forested slopes. The thermal waters flow down through narrow channels with little disturbance to the forests, forming silica sinters. Solar-driven evaporation promotes silica precipitation and sinter growth. These sinters are subdivided into four depositional facies characterised by the incorporation of abundant modern plants from the surrounding forests, together with temperature-specific microbes. The forested hot-spring setting may serve as a valuable modern analogue for understanding the formation processes of plant-rich fossil sinters. The model provides a broader basis for palaeoecological interpretations of silica sinter Lagerstätten throughout the geological record.

Lycophytes are the most ancient lineage of vascular plants, first appearing during the Silurian (~420Ma). They underwent a divergence into two lineages: zosterophylls and lycopsids. Despite the zosterophylls initial success, they underwent a rapid decline during the mid-Devonian and vanished by the end-Devonian. By contrast, lycopsids diversified, and persist today. Explaining these divergent evolutionary trajectories remains a central question in plant evolution. Increased occupation of terrestrial environments forced early land plants into competition for space: evolutionary innovations such as roots may have provided the lycopsids with greater ecological flexibility and resilience to environmental change, underpinning their long-term survival. This project addresses this using a trait-based approach, with the first reconstruction of a zosterophyll based on 3D data. Specimens are from the Rhynie Chert Lagerstätte, a fossilised hot spring system preserving specimens in exceptional, 3D detail thanks to the silicious rich waters from the hot spring vents. Using a novel serial grinding tomography called ‘digital fossil mining’ has allowed us to sequence entire specimens encased in rock- capturing thousands of images which can be used for reconstruction. Preliminary results reveal the zosterophyll Trichopherophyton teuchansii lacked the characteristics of true roots, including root caps and hairs. In addition, it had a helical arrangement of sporangia. 3D reconstructions allow us to draw side by side comparisons between the characteristics of rooting systems, shoots and reproductive structures in lycopsids and zosterophylls and refine our understanding of key evolutionary innovations in the earliest land plants.

Recent fossil discoveries and advances in plant phylogeny have renewed debate about the most recent common ancestor (MRCA) of land plants and the evolution of its fundamental organs and tissues. Here, we re-examine the conducting system of Horneophyton lignieri (≡ Hornea lignieri), one of seven land plants preserved in the Rhynie Chert. Kidston and Lang (1920) originally described its conducting tissues as a stele composed of a ring of phloem surrounding a solid xylem core of tracheids—a view largely accepted in subsequent literature, though not without challenge.

Using confocal laser scanning microscopy combined with 3D modelling, we obtained higher resolution reconstructions of cell morphology than previously possible with white-light microscopy. Our analyses show that H. lignieri lacks discrete xylem and phloem tissues, contradicting long-standing interpretations. Instead, the conducting system is dominated by tissues bearing transfer-cell-like wall structures, comparable to those recently documented in charcoalified early land plants from other localities. Both cell type and cell wall architecture vary systematically with position in the plant.

These findings suggest that the ancestral conducting system of land plants comprised a single, multifunctional cell type capable of both solute transport and water conduction. Consequently, H. lignieri should not be regarded as a tracheophyte. Our results support emerging models in which the MRCA of land plants possessed a morphologically and cellularly complex body plan.

Despite representing an inherent phase in the life cycle of embryophytes, gametophytes are exceedingly rare in the fossil record compared to sporophytes. Nevertheless, such findings are critical for understanding the physiology and evolution of early land plants. The Early Devonian Rhynie chert (UK) has been instrumental in this regard, notably through the works of Remy and Remy (U. Münster) in the 1980s, who documented the first unequivocal examples from this assemblage. Over the years, additional putative gametophytes of early land plants have been described in other assemblages, including those attributed to Sporogonites, a possible bryophyte, and Cooksonia, the earliest known vascular plant. However, although widely acknowledged, the interpretation that thalloid structures represented their gametophytes remains tentative. Here, we report gametophytes preserved in organic connection with sporophytes of Sporogonites and Cooksonia from the Lochkovian compression assemblage of Impofu Dam (South Africa). Sporogonites is reconstructed as a polysetous organism comprising an axial unbranched gametophyte bearing distally multiple unbranched sporophytes. The gametophyte of Cooksonia consists in an isotomously-branched axial system terminating in multiple archegoniophores, each supporting sporophyte axes markedly narrower than the subtending gametophyte axis. These findings refute previous interpretations of the gametophytes of both taxa as thalloid structures and demonstrate that the sporophytes of the earliest land plants remained nutritionally dependent on the gametophyte. Importantly, since these taxa represent the earliest known representatives of their respective lineages, new insights into the ancestral life cycle of land plants can be provided.

Stomata are openings in the epidermis of plants, bounded by turgor-driven guard cells that open and close to control water loss, gas exchange, and regulate internal temperature. The fossil record preserves evidence that stomata are ancient and highly conserved features that develop on above-ground plant organs of the majority of plant groups and were likely present in the common ancestor of all extant plants. Furthermore, phylogenomic and comparative functional and developmental studies suggest that early land plants possessed a large complement of the stomatal genetic toolkit and were functionally similar to living groups with the capacity to respond to changes in atmospheric CO2 concentration. Here, we leverage a new technique to extract larger fragments of exceptionally preserved fossils from the Rhynie chert (~407ma, Scotland, UK) fossil site, combined with cell segmentation to quantify stomata and epidermal patterning in leafless species using Aglaophyton majus and Rhynia gwynne-vaughanii as case studies. Our results show that stomata are distributed around the full cylindrical surface of axes and aligned with the growth direction. Moreover, stomatal density is highly variable within species, significatively lower than previous estimates and much lower than in modern leaves, and lacks a correlation with axis diameter. Our statistical analysis of cell size and shape confirms the presence of subsidiary cell-like cells in both species. This combined evidence suggests that a robust and complex epidermal patterning mechanism was present in A. majus and R. gwynee-vaughanii.

Numerous lignitized fruits and seeds have been recovered from commercial clay pits of the middle Eocene Cockfield Formation of the Claiborne Group. One fruit type, comprising five specimens, previously studied with reflected light and scanning electron microscopy, was further investigated with Keyance shadow effect microscopy and micro-CT scanning technology to elucidate the inner morphology. The fossils are lenticular endocarps, nearly circular in apical view. Four, five, or seven cylindrical locules, most or all with an enlarged seed, are arranged in a ring in the interior of the endocarp. Near the upper part of the endocarp are subapical extra-locular cavities alternating with the locules. Near the equatorial rim of the endocarp are lateral extra-locular cavities, equal in number to the locules. The exact means of emergence of the radicle is uncertain, but it appears that the radicle penetrates a small opening at the apex of the locule or pushes through the very thin upper layer of the locule. The characters of the fossil are mostly shared with those of fruits of the subfamily Spondioideae of the family Anacardiaceae. The fossils, however, do not match any single modern or fossil genus, especially differing in the method of germination. Therefore, a new genus of Anacardiaceae is proposed. This new genus, along with other extant genera, including Cyrtocarpa, Dracontomelon, and Lannea, and extinct genera, including Pentoperculum, Pseudosclerocarya, and Spondicarya, known from the Eocene of North America and Europe, shows that fruits of Anacardiaceae, especially Spondioideae, were already diverse and widespread by the Eocene.

The early Late Miocene hominid locality Hammerschmiede (OSM4, MN9, Bavaria, Germany) is well known for its diverse and important fossil vertebrate fauna, but the botanical record remains poorly understood. The unique carpoflora from a fine grained river channel fill (HAM 4, channel lag/ upper bars) has been collected and studied over the last years. The depositional setting reflects neither a typical limnic carpoflora nor a bedload carpodeposit sensu Gee (2005). The assemblage, with over 2000 finds, shows an overwhelming dominance of Vitaceae and only few aquatic and terrestrial elements.
A key initial question was to verify the fossil status of several exceptionally well preserved endocarps that are morphologically indistinguishable from modern counterparts. For these specimens, we combine SEM-EDX and organic petrography, quantifying elemental compositions (including carbon and nitrogen) and documenting maceral assemblages, reflectance and pyrite occurrence in polished blocks, in comparison with extant and independent fossil reference material. On this basis, the taxonomy of the seeds and fruits is reassessed, allowing at least ten genera to be securely documented from HAM 4 and substantially expanding the known carpological record of the site. Differences in preservation are then used to explore taphonomic pathways and possible transport mechanisms, including hydraulic sorting and biotic enrichment. In a final step, the combined taphonomic and taxonomic indicators are used to outline a first botanical palaeoecological interpretation of the HAM 4 floodplain system, focusing on likely source habitats and the broader placement of the assemblage within warm temperate Neogene floristic elements and complexes sensu Mai (1995).

The Plio–Pleistocene travertine flora from Dreveník (Slovakia) represents an important macrofloral assemblage across the Late Pliocene–Early Pleistocene transition. The Dreveník flora comprises a total of 37 taxa, including 35 plant species and two family-level taxa. Four gymnosperm species representing four genera and one family-level taxon were recognised in the studied material, including Ginkgo adiantoides (Unger) Heer, Torreya cf. nucifera Siebold & Zucc., Pinus sp. and Picea sp. The remaining 31 species belong to angiosperms and represent 24 genera together with one additional family-level taxon. The fossil taphocoenosis includes, among others, Cercidiphyllum crenatum (Unger) R.W.Br., Liquidambar europaea A.Braun, Cotoneaster sp., Zelkova zelkovifolia (Unger) Bůžek & Kotl., Ulmus cocchii C.T.Gaudin, Fagus haidingeri Kováts, Betula subpubescens (Göpp.) G.Worobiec, Populus tremula L., and Phillyrea aff. latifolia L.

Particularly significant is the occurrence of well-preserved acarodomatia in leaves assigned to Parrotia persica (DC.) C.A.Mey. Both pit- and pocket-type domatia are present in the axils of secondary veins and represent an important diagnostic feature supporting assignment of the material to the extant species rather than to morphologically similar genera of Hamamelidaceae. The studied material therefore contributes to the discussion of the taxonomic value of domatia in fossil Hamamelidaceae and to the distinction between Parrotia persica and the broadly interpreted fossil species Parrotia pristina (Ettingsh.) Stur. The Dreveník flora is important for its mixture of Neogene and extant taxa and represents one of the latest occurrences of typical Neogene taxa in the region.

The Western Himalaya, with its unique biodiversity, complex topography and sensitivity to both South Asian Summer Monsoon (SASM) and Western Disturbances (WDs), acts as a key region to decode past climatic and associated ecological changes. Here we present a high-resolution multi-proxy based vegetation and climate reconstruction, and human-environment interactions in the Western Himalaya since ~21.7 ka BP, using peat and sediment records from Sangla Kanda, Suptal Lake, and Bhojbasa Kame Terrace.

Modern pollen-vegetation relationships were established using surface samples, forming a baseline for interpreting fossil pollen data. Multiproxy analyses, including palynology, TOC%, stable carbon isotopes (δ¹³C) and microcharcoal combined with AMS radiocarbon dating, enabled detailed reconstruction of past environmental conditions. The records captured major climatic events such as the Last Glacial Maximum , Younger Dryas , Early Holocene warming , 8.2 ka event, 4.2 ka event, Medieval Warm Period and Little Ice Age.

Results indicate that vegetation responded sensitively to monsoon variability, with steppe taxa dominating during dry phases and arboreal expansion during moist intervals. High-altitude sites primarily reflect climatic forcing, whereas mid-elevation sites show stronger anthropogenic influence. Evidences of human activities are evident by the presence of Cerealia Poaceae, Cannabis, Rosaceae (Apple, Apricot) pollen and microcharcoal, particularly after ~5 ka BP with intensification during last 2 millennia.

The study demonstrates regionally coherent climatic events but varied in expression with altitude and local conditions. It highlights the combined role of monsoon variability, elevation, and human activity in altering the Himalayan ecosystems, providing critical insights for understanding future ecological scenario.

Quercus subgenus Cerris is one of the two subgenera in Quercus, with around 140 species in the sections Ilex, Cerris and Cyclobalanopsis. The sects. Ilex and Cyclobalanopsis are mostly evergreen, while the sect. Cerris is almost deciduous. They prefers to different ecological habitats, climate and geographical ranges, providing palynologists a key to reconstruct vegetation and associated climate using pollen. However, classifying subgenus Cerris pollen is challenging due to overlaps in pollen size, sculpture and aperture under LM or even SEM. This study focuses on aperture and sculpture of three sections of the subgenus Cerris to refine diagnostic keys.
Pollen sculpture patterns under LM between the sects. Cyclobalanopsis and Ilex are very similar, but can be largely distinguished under SEM according to aggregated granular with the sect. Cyclobalanopsis and rod-like/rugulate elements with the sect. Ilex. The sect. Cyclobalanopsis contains about 90 species native to tropical and subtropical Asia, thus their fossil pollen can be practically indicative warm and humid climate associated with Eastern Asian Monsoon, while pollen of mountain oaks in western alpine areas of China can be an indicator of cold and seasonal dry climate. Pollen sculpture of the sect. Cerris shows scattered verrucate, and its pollen type is tricolpate, thus safely to be distinguished from the sects. Cyclobalanopsis and Ilex (mostly tricolporoidate-tricolporate). To improve paleoecological interpretation, SEM-aided identification and calibration are effectively used in classifying subgenus Cerris pollen types into different sections in western China’s alpine lakes, and improved vegetation and climate reconstruction, spanning LGM to late Holocene.

In the Iberian Peninsula, pine forests played a fundamental role in shaping Late Quaternary landscapes, both through the occupation of treeless areas following fires and climate change, and through the stabilization of environments less suitable for other arboreal communities (sands, steep slopes, etc.). Based on macrofossil evidence from different regions of the Iberian Peninsula, it is now well established that Pinus sylvestris L.- Pinus nigra J.F. Arnold group, and Pinus pinaster Aiton occupied areas very close to the Atlantic coast during the Late Pleistocene, before retreating towards higher elevations or latitudes with the Holocene climate amelioration.

Nevertheless, the scarcity of Holocene palaeobotanical evidence regarding coastal P. pinaster and montane P. sylvestris populations leaves the autochthonous status of the present populations uncertain. Within the framework of the ODISEA project, botanical macro-remains and micro-remains of three sites have been studied between 2021 and 2025. The results demonstrate, for the second half of the Holocene: a continuous although low-frequency presence of Pinus in the Serra do Gerês (Portugal) in a landscape dominated by heath; an uninterrupted coastal persistence of Pinus in Southwestern Iberia, including P. pinea and P. pinaster, with sparse Quercus representation; and the long-term stability of P. sylvestris forests in the Central System, particularly in the Sierra de Guadarrama (Spain) even at mid-elevations (rather than exclusively at high altitudes).

This publication is part of the project PID2020-119836GB-I00 funded by 482 MCIN/AEI/ 10.13039/.

Extensive work has been done on modelling plant hydraulics incorporating all organ parts of extant plants. However, these approaches have only initially been applied to extinct plants, yet as whole-plant concepts are exceptionally rare in the fossil record. During the last decades, some studies attempted to create a conductivity model for the medullosans based on the dimensions and interconnectivity of the tracheids in the secondary tissue only. The medullosans were key elements of late Paleozoic tropical ecosystems. They exhibited large and complex fronds that could reach several meters in length, attached to slender stems with a complex dissected stele and numerous vascular bundles, pointing to a great water conductivity potential. We apply innovative modelling approaches to detailed architectural and anatomical reconstructions of specimens from the Chemnitz Fossil Forest (early Permian), both at tissue and cellular scales. The hydraulic model encompasses the stem and frond vascular systems including their interface.
Preliminary results show that the peripheral vasculature (PVS) in Medullosa stellata conducted 98% of the stem water, whereas the pith vascular strands (CAS) conducted only 2%. This result supports our previous hypothesis that the function of the CAS was to supply the stem apex and leaf primordia with water, whereas the PVS mainly supplied the active fronds. This result represents a first step towards assessing the hydraulic functioning of the extinct medullosans to better understand their macroevolutionary history, including radiation and extinction patterns.

Coal balls with anatomically plant remains have largely been used for the reconstruction of the Permo-Carboniferous peat-forming vegetation. New materials of coal balls have recently been found from the Lower Permian Taiyuan Formation of Yangquan City, Shanxi Province, North China. The peat-forming plants of the Asselian No. 11 coal seam include Lepidodendron spp., Lepidophylloides sp., Sigillariopsis taiyuanense, Stigmaria spp., Sphenophyllum spp., Astromyelon sp., Stewariopteris sp., Botryopteris sp., Etapteris sp., Psaronius spp., Pecopteris spp., Scolecopteris spp., Myeloxylon sp., Sutcliffa sp., Shanxioxylon taiyuanense, Cordaites spp., and Amyelon spp.. Quantitative analysis demonstrate that cordaitaleans were the dominant elements of the peat-forming forest, accounting for about 56.9 % of the total biomass. Tree ferns and sphenopgytes were subdominant, taking 32.8 % and 9.7 % respectively. Lycopsids and seed ferns were very rare. The composition of the peat-forming vegetation is different from that of the non-peat-forming communities in North China Craton, where the seed ferns and lycopsids took the majority of the assemblage during the early Permian. Our finding represents the fifth locality with early Permian coal balls in North China. Comparing with these peat-forming communities, it shows a great heterogeneity in floral composition of peat-forming swamps. Cordaitaleans were the dominant components of the coal-forming vegetation, accounting for 45-50 % of the biomass, whereas lycopsids accounted for 20-25 % in the Xishan, Yanzhou, and Xuzhou coalfield. However, lycopsids were overwhelmingly dominant in the Ningwu coalfield, constituting at least 68 % of the assmblage.
Key words: Taiyuan Formation; Cathaysian Flora; Coal-ball flora; Peat-forming swamp; Permo-Carboniferous

The traditional interpretation of Gondwana sediments as exclusively fluvio-lacustrine has been increasingly challenged by evidence supporting Permian marine incursions following the Late Palaeozoic Ice Age. Both peninsular and extra-peninsular Gondwana successions in India preserve indications of marine influence within predominantly non-marine sequences, reflected in fossil occurrences and sedimentological signatures. However, many fossil-bearing horizons have been degraded or lost due to mining, erosion, weathering, fossil collection, and limited accessibility.

This study employs a multiproxy approach integrating biotic and abiotic datasets to reassess marine-influenced strata from several sub-basins of the Damodar Valley Basin and Gondwana-equivalent successions in Sikkim. Samples from opencast mines and outcrop sections were analyzed using organic and inorganic geochemical techniques. Fourier Transform Infrared Spectroscopy (FTIR) identified carbonate absorption bands at 1460 cm⁻¹ and 880 cm⁻¹, suggesting marine influence. Biomarker analyses revealed abundant C29 regular steranes and 4-methylsteranes, indicating predominantly terrestrial organic matter deposited under brackish conditions. Trace-element geochemistry from the Giridih Basin, particularly Th/U and Sr/Ba ratios, points to deposition in brackish to shallow-marine environments. Elevated sulphur concentrations and the occurrence of framboidal pyrite in the Ashoka coal seams further support episodes of marine incursion. Palynological assemblages from Sikkim contain leiospherids, indicating affinity with brackish to marine settings, while ichnological evidence from the Ramgarh Basin, including burrows such as Diplocraterion and Skolithos, is consistent with marine depositional conditions.

Together, these independent lines of evidence provide strong support for marine influence during Barakar sedimentation and suggest a persistent marine connection across multiple Gondwana basins during the Permian.

The Early Triassic of the Sydney Basin (southeastern Australia) records successive floral communities dominated by arborescent seed ferns (Peltaspermales, Umkomasiales) and conifers (Voltziales), and shrubby isoëtaleans (Pleuromeiaceae, Isoëtaceae). These changes track the climatic instability following the end-Permian event (ca. 252.3−251.9 Ma), likely driven by recurrent outgassing pulses from the Siberian Traps Large Igneous Province after its main eruptive phase. Stable carbon isotope stratigraphy links the floristic turnovers to extreme warming during the late Smithian thermal maximum (ca. 249.9−249.4 Ma), followed by two cooling phases: the Smithian-Spathian event (SSE; ca. 249.4−249.1 Ma), and the end-Early Triassic event (EETE; ca. 248.1−247.4 Ma).

Between the SSE and EETE lies a distinctive interval of kaolinitic mudrocks with high hematite content, characterised by pervasive oxidation that imparted in them a red colouration (i.e., red bed). X-ray fluorescence (XRF) data indicate intense chemical weathering, reflected by sodium- and potassium-oxide depletion and chemical index of alteration values averaging ~92. Despite this weathering signature, recovered palynomorphs exhibit unexpectedly remarkable preservation. Sedimentological evidence indicates a major palaeocurrent shift during the upper Early Triassic, coinciding with a geochemical trend revealing a change in sedimentary provenance from plutonic to volcanic sources. Biostratigraphy demonstrates that palynomorphs were contemporaneous with red bed deposition, suggesting that sediment likely underwent an initial phase of weathering prior to being transported and deposited, followed by additional alteration under a warm, humid Spathian climate.

These findings highlight that continental red bed deposits can remain viable targets for palynological sampling despite superficial sedimentary and geochemical evidence for intense weathering.

The Dolomites are well-known for their exceptionally well-preserved Triassic successions, providing key records of the Carnian Pluvial Episode (CPE). Occurring around 234 to 232 Ma, the CPE corresponds to a major phase of global climatic change during the Late Triassic, commonly associated with increased humidity and enhanced siliciclastic input into sedimentary basins, as well as significant biotic turnover affecting both terrestrial and marine ecosystems (Dal Corso et al., 2020). This study focuses on sections located within the Heiligkreuz Formation (Dolomites, Northern Italy) (Pecorari et al., 2023). The aim is to identify sedimentological and palynofacies signals associated with the CPE. Lithological observations are integrated with palynofacies analysis and carbon isotope data. Initial results on particulate organic matter indicate a strong dominance of phytoclasts thoughout the sections, with limited variability and no significant variation in the relative abundance translucent and opaque phytoclasts. In contrast, palynomorphs, including spores and pollen grains, are generally well preserved and relatively abundant.

Dal Corso, J., Bernardi, M., Sun, Y., Song, Y., Seyfullah, J. L., Preto, N., Gianolla, P., Ruffell, A., Kustatscher, E., Roghi, G., Merico, A., Hohn, S., Schmidt, R. A., Marzoli, A., Newton, J. R., Wignall, B. P. & Benton J. M. (2020). Extinction and dawn of the modern world in the Carnian (Late Triassic), Sciences Advances, 6(38), 1-12.
Pecorari, M., Caggiati, M., Dal Corso, J., Cruciani, G., Tateo, F., Chu, D., Gianolla, P. (2023). Weathering and sea level control on siliciclastic deposition during the Carnian Pluvial Episode (Southern Alps, Italy). Palaeo3 617, 111495.

Algae represent an exceptionally diverse assemblage of organisms that belong to evolutionarily distinct lineages. Unfortunately, there is no evidence of fossil algae from the Cenozoic sedimentary strata to date. In this research, we present the first evidence of three multicellular algal specimens from the Miocene: i) tree-like, branched algae akin to contemporary Cladophora Kütz. (Cladophoraceae: Cladophorales: Chlorophyta), ii) elongated, filamentous, unbranched algae resembling modern Zygnema C. Agardh (Zygnemataceae: Zygnematales: Charophyte), and iii) Moniliform "bead-like" filamentous algae similar to Neo-Proterozoic algae Arctacellularia Hermann found as a mixed algal tuft on cuticular fragments of a compressed monocot leaf recovered from the middle Siwalik sediments (Late Miocene; 12–8 Ma) in Himachal Himalaya, India. This extraordinary preservation of epiphytic fossil algae offers insight into the freshwater conditions that existed during the Siwalik depositional period (Late Miocene). Furthermore, this report contributes significant information regarding the evolution of lower vascular plants throughout deep time.

In today's ecosystems, various groups of organisms live in dead plant material; in most cases, these are saprotrophs that participate in biological decomposition, thereby returning the plant components to the nutrient cycle. In the Early Devonian Rhynie ecosystem, this is unlikely to have been much different; however, descriptions of such organisms are rather rare, even though decaying plant parts and even entire accumulations of them (litter layers) are frequently found in the chert. Here, I present several distinctive microscopic structures found in partially decomposed land plant axes from the Rhynie chert, which clearly belong neither to the plant itself nor to any known plant-associated organism. Rather, they appear to be the remains of other life forms that had already completed their activities within the plant some time before it became fossilized, either as parasites or as saprotrophs, or they originate from organisms that simply used plants or their dead parts as a habitat. However, some of these could also be artefacts that closely resemble natural structures. Nevertheless, it is worthwhile to document and critically evaluate all of these structures, as they too can provide insights into the biodiversity of plant-associated and possibly saprotrophic life in the Rhynie ecosystem.

Microorganisms have been key components of terrestrial ecosystems for over 400 million years, performing roles similar to those they fulfill in modern environments. Despite their frequently excellent preservation in ancient fossil deposits, microorganisms are challenging to document due to their small size and the limitations of brightfield microscopy. Fluorescence-based imaging techniques offer new ways to overcome these limitations by improving image quality, enabling three-dimensional modelling of microscopic structures, and distinguishing different organic materials.

We applied these methods to cherts – silica-rich sedimentary rocks – formed in environments dating from 400 to 300 million years ago. Key deposits include the Rhynie cherts (Scotland), the Massif central cherts (France), and coal balls – carbonate mineral precipitates that formed in the original peat before it underwent coalification – from the UK. These deposits all offer a record of some of the earliest interactions between plants and microorganisms and reveal how they adapted to the changing face of terrestrial habitats.

Confocal Scanning Laser Microscopy (CSLM) reveals detailed structures through high-resolution optical sectioning, while Fluorescence Lifetime Imaging (FLIM) differentiates structures based on fluorescence decay linked to chemical composition. These combined methods allow microorganisms to be studied with greater precision and help clarify the biological affinities of ancient microorganisms and the nature of their associations with plants.

The affinities of Prototaxites are currently strongly debated. A further question is why Prototaxites is found together with Pachytheca in Silurian/earliest Devonian sediments from their earliest records. The small number of large, trunk-like, Emsian and younger Prototaxites share similar anatomy with the more numerus older fragments. All comprise aggregations of tubes that show similarities with fungal anatomy, an interpretation reinforced by their frequent occurrence with fragmentary hymenial tissues and geochemical evidence of heterotrophic nutrition. By contrast Pachytheca comprises spherical colonies of septate filaments that radiated from the central interweaving mass though a presumed mucilaginous matrix, with geochemistry indicative of autotrophy.
The above data were largely obtained from carbonized fossils. Both taxa are very rare in the Rhynie chert. Nevertheless, of the pachythecas studied here, three were juvenile enclosed in a partial hymenial layer, the fourth being positioned close to sterile P. taiti, hymenial layers and potential cords. Considering Prototaxites, in addition to the above, there are two examples of P. taiti recorded in an assemblage of presumed drifted plant and microbial remains.

We found no evidence for organic connection in this allochthonous material, but the consistent association of the two taxa is strongly suggestive that they originally colonised the same catchment region, and this was very rare in an area dominated by hot springs. Pachytheca being spherical could have rolled through pools, only becoming trapped among accumulations of shed ephemeral fertile material of Prototaxites. The origin of the fragments of typical Prototaxites escapes us.

Prototaxites was the first giant organism to inhabit the terrestrial surface, represented by columnar fossils reaching up to eight meters in height from the Early Devonian. Its peculiar anatomy has led to debate over its systematic affinity for more than 165 years. Currently, two main hypotheses exist: Prototaxites was either a fungus or a member of an entirely extinct lineage. Today, morphological observations can be complemented by molecular-scale analytical techniques, providing new data on fossil material and shedding light on longstanding palaeontological questions. Here, we demonstrate how supervised and unsupervised machine-learning approaches applied to Fourier Transform Infrared Spectroscopy (FTIR) data from iconic 407-million-year-old Rhynie Chert fossils, including new and historical specimens of Prototaxites taiti, can help resolve questions surrounding their uncertain biology. We contrasted the molecular composition of Prototaxites with that of fungi and other fossils preserved with it in the chert. Our results reveal that Prototaxites was chemically and anatomically distinct from contemporaneous fungi. Coupled with high-resolution morphological investigations using confocal laser microscopy, and biomarker analyses, these findings cast doubt on the fungal affinity of Prototaxites, instead suggesting that this enigmatic organism is best assigned to a distinct extinct eukaryotic lineage. Moreover, these results interrogate the biological nature of other nematophytes, like Nematoplexus.

Before land plants came to dominate terrestrial habitats, metre-tall, columnar organisms of unknown systematic classification – known by the generic name Prototaxites – were the largest land-dwelling organisms during the Early and Middle Devonian. The size and biomass of these organisms suggest that Prototaxites provided a potentially rich food source for arthropods and other terrestrial organisms capable of utilising their robust tissue.

Our study of three silicified Prototaxites stem fragments revealed a complex system of tunnels, some of which feature chamber-like expansions and are filled with coprolites of two morphotypes: both are characterised by a prismatic shape with a hexagonal cross-section and differ only in size and shape. The partial healing of the feeding tunnels, similar to that recognised in modern fungi, proves that the tunnels were formed during the organism’s lifetime.

The fact that hexagonal coprolites are now found exclusively in insects, which possess six rectal pads for shaping and compressing faecal matter, suggests that insects adapted to an endophagous lifestyle already existed in the Early Devonian. The simultaneous presence of smaller, elongated coprolites in the same feeding tunnels points to coprophagy – the earliest evidence to date of this behaviour in terrestrial land-dwelling organisms.

The new discovered feeding tunnels in Prototaxites at various early Devonian sites in Germany indicate that insects appeared much earlier in early terrestrial habitats, a finding that is consistent with the predictions of molecular phylogenetic studies on the emergence of the Pterygota.

The Rhynie cherts (~407 Ma), a Devonian hydrothermal hot spring system, contains the most complete early terrestrial ecosystem (Garwood et al., 2020; Rice et al., 2002). Taxonomically diverse fossilised arthropods (Dunlop & Garwood, 2018) within the cherts are preserved in a precipitated silica sinter in cellular detail, providing unparalleled insight into the form and function of early terrestrial communities. Here, we utilise non-destructive high-resolution 3D imaging of Rhynie chert thin section collections to assess microscopic arthropod sensory structures. We identify a new structure within the hairs of Palaeocharinid Trigonotarbids, revealing a chemosensory lifestyle for the earth’s oldest terrestrial predator, revising our understanding of how the first terrestrial arthropods adapted to life on land.

The vegetation history of Lake Srebarna in northeastern Bulgaria spans the Holocene period, tied to climate fluctuations and millennia of human land use. Pollen analyses provide a detailed timeline of regional flora and landscape changes. Today, Lake Srebarna is a shallow freshwater lake that transitions into the Danube River floodplain. The aquatic and wetland flora is highly distinct. The vegetation is dominated by massive rcommunities of Phragmites australis and Typha species. Open water sections support Nymphaea, Hydrocharis, and Potamogeton. Adjacent wet meadows support rare, protected aquatic plants like Salvinia natans and Stratiotes aloides.

Throughout the Holocene, climate and landscape in this area were shaped by a complex interplay of natural climate variability, Danube flooding regimes, and human activity. The Danubian Dobrudza and Ludogorie districts were dominated by extensive oak woods, hornbeam (Carpinus betulus), lime (Tilia), elm (Ulmus), and hazel (Corylus) in the Atlantic Period (ca. 8,000–5,000 BP). Later (ca. 5,000–2,500 BP), mixed oak woods persisted, with lime and elm decreasing, and hornbeam and beech (Fagus) becoming prominent. Pollen records show the first significant anthropogenic impact (ca. 2,900–1,600 BP), marking early pastoralism and cereal cultivation. Woodlands began to degrade and open up due to agricultural clearing. The Modern Period is characterized by extensive woodland clearance and the introduction of non-native species (such as Pinus nigra, poplar, and black locust) into abandoned agricultural lands surrounding the lake.

Acknowledgments: The authors thank Horizon Europe and the DANUBE4all Project (GA no. 101093985) for financial support.

A central question in palaeoenvironmental research is whether and how past climatic changes influenced shifts in settlement patterns, subsistence strategies, and land use. This study investigates the interactions between vegetation dynamics, climate variability, and human land-use practices in northeastern Germany during the Late Bronze Age to Early Iron Age (ca. 1270–580 BC), a period marked by major socio-environmental transformations across Europe. There is a significant gap in high-resolution palaeoenvironmental research from northeastern Germany. To address this, we apply a multiproxy approach to a sediment core from Lake Kleiner Tornowsee (KTO). By combining pollen analysis, geochemical proxies, tephra identification, local pollen-based climate reconstructions, and climate model simulations, this research reconstructs environmental and anthropogenic changes and explores how settlement dynamics and land-use intensity responded to climatic variability, cultural developments, and environmental stress during the Late Bronze Age and Early Iron Age.

Keywords: Cultural transformation, Settlement dynamics, Climate change, Pollen-based climate reconstruction, Climate model simulation

The continuous interaction between humans and the environment has strongly shaped the plant landscape of southern Greece. In particular, the Peloponnese, with its complex topography and climatic variability, encompasses centuries of human occupation. A plethora of palaeovegetation records derive from Peloponnesian lowland regions; however, the mountainous areas remain poorly documented. Within this context, the Rakita wetland, located on a plateau of Mount Panachaiko (northwestern Peloponnese), represents a valuable palaeoenvironmental archive. The high-resolution Rakita record provides insights into past vegetation dynamics, as well as evidence of land use and landscape exploitation over the last millennium. The rich palynological archive indicates a transition from open vegetation to a more forested landscape in the Middle Byzantine period. Up-core, a retreat of woodland is observed, associated with the intensification of human activity, particularly animal husbandry and agriculture. In the course of the Ottoman/Venetian periods, a gradual expansion of the forest is recorded, although anthropogenic influence remained significant. Finally, the 19th century CE is marked by a shift in land cover towards herbaceous-dominated vegetation. Bearing a decadal temporal resolution, the upper part of the sequence allows direct comparison of the palynological findings with detailed historical sources, including taxation registers, cadasters, and censuses produced by the Ottoman and Venetian authorities.

A well-preserved biota consisting of plant macrofossils, palynomorphs, insects, molluscs, crustaceans, actinopterygians and hybodontiforms has recently been recovered from the El Mono Formation in the Atacama Desert. Paleontological and sedimentological data indicate that this assemblage was deposited in a dominatingly lacustrine setting. The quality of preservation justifies classifying this site as a Fossil-Lagerstätte. Systematic sampling carried out since 2023 has yielded a rich flora dominated by the seed fern Dicroidium and its associated reproductive structures Umkomasia and Fanerotheca, alongside the sphenophytes Equisetites and Neocalamites. Less represented elements include cycadaleans, bennettitaleans, putative lycophytes and conifers, although this relative composition likely reflects a taphonomic and transport bias. This assemblage is consistent with a typical Late Triassic Gondwanan Dicroidium flora, reflecting a period of floral adaptation toward increasingly humid environments. Palynomorphs expand the floristic diversity, revealing the additional presence of bryophytes, dipteridaceans/matoniacean ferns, caytonialean seed ferns and a higher diversity of conifers, belonging to the voltzialean and coniferalean linages. Furthermore, the recurrent presence of charcoal points to paleowildfires, likely associated with warmer conditions punctuating an otherwise humid climate. Preliminary U-Pb detrital zircon geochronology data constrain the depositional age to the Middle to Late Norian (Maximum Depositional Age of ~211–214 Ma), coincident with the global record of enhanced warm and humid conditions during this interval. The El Mono flora thus provides a snapshot of the intensifying climatic conditions of a highly dynamic environment at the dawn of the modern ecosystems in Southwestern Gondwana.

The Yangcaogou Flora, a well-preserved Upper Triassic plant assemblage from Western Liaoning, NE China, comprises 77 species in 34 genera and provides a window into East Asian terrestrial ecosystems within a Pangaea framework. We quantify its taxonomic diversity and regional heterogeneity to illuminate the tectonic, climatic, and biogeographic controls on vegetation in Late Triassic terrestrial ecosystems. The U–Pb zircon geochronology places deposition in the Norian–Rhaetian interval (~226 Ma), enabling robust cross-basin correlations. A comparative analysis between the Ordos and Yangcaogou Basins reveals pronounced regional differences in diversity. Our results highlight how tectonics, climate, and biogeography jointly sculpt East Asian Late Triassic ecosystems, and the co-occurrence of northern and southern floristic elements also indicates the unique climatic regimes in Pangaea, offering insights for reconstructing Late Triassic paleoclimates and paleogeography in the region.
Keywords: Liaoning, gymnosperms, Norian, paleoclimate, plant fossils, U-Pb dating

Pararaucaria patagonica seed cones are remarkably well-suited for in-depth study of their phyllotaxis and architecture thanks to the highly detailed preservation of their gross morphology and anatomy. Originating from the Middle Jurassic of Argentina, these cones can be either long and cylindrical or short and ovoid at maturity. Although superficially distinct, numerous anatomical studies have confirmed that both forms belong to Pararaucaria patagonica. However, it is currently unknown how these cones’ phyllotaxis and construction result in this varied morphology. Here we present two strategies for the construction of slender conifer cones: stretching or stacking the cones’ seed spirals. Micro-CT and digital segmentation were used to reconstruct the internal seed arrangement of Pararaucaria patagonica in three-dimensions, revealing 2,3 phyllotaxis. Statistical analysis shows that cone width does not increase with length, but their parastichies rotate more times around the axis as the cone lengthens. Because Pararaucaria is extinct and has no living relatives, Picea orientalis was selected as a modern analog representing a long, thin cone. Although morphologically similar, these cones have 3,5 phyllotaxis with widths that scale with cone length. Additionally, its parastichies stretch to fit increased cone length, instead of adding more rotations. In contrast to Pararaucaria and Picea orientalis, araucariaceous cones, exemplified by Araucaria mirabilis, widen their girth and parastichies instead of lengthening. Furthermore, we demonstrate that the ontogeny of a fossil seed cone can be predicted by its phyllotaxis and parastichy chirality. These results shed light on the relationship of phyllotaxis and conifer seed cone construction.

Biotic pollination represents a key mutualistic interaction in terrestrial ecosystems, strongly influencing the evolutionary history of plants and animals, yet its origins remain debated. Palynivory, the consumption of spores and/or pollen, has been proposed as a precursor to insect-mediated pollination. Here, we review the fossil record of invertebrate bromalites (coprolites and gut contains) containing spores and pollen from non-angiosperm plants across the Paleozoic and Mesozoic, synthesizing data accumulated since earlier studies. Our analysis reveals a stepwise evolutionary trajectory. Early records from the Silurian–Devonian are dominated by detritivorous consumption of a variety of spores, indicating opportunistic feeding. During the Carboniferous, increasing plant and insect diversification coincides with greater dietary specialization and the first evidence of pollen consumption. In the Permian, a shift from sporivory- to pollinivory-dominated systems occurs, likely linked to environmental changes and the rise of seed plants. In contrast, the Mesozoic record is sparse, limiting interpretation of later evolutionary trends. The fossil record of palynivory is strongly biased by preservation, methodological limitations, and uncertainties in the botanical affinity of the spores and pollen. Although often considered a precursor to biotic pollination, direct links between pollen consumption and gymnosperms pollination mutualisms remain difficult to establish. Among the different non-angiosperm plants supposed to be involved in pollination, only cheirolepidiacean pollen grains have been found in bromalites so far. This review highlights the need for standardized and targeted methodologies to better document palynivory and clarify its role in the evolution of plant–insect interactions.

The detection and documentation of rare, early angiosperm fossil pollen remain challenging due to low abundance in Lower Cretaceous deposits and limitations of traditional palynological microscopy approaches. The newly developed All-in-One Mounting Method (A1MM) introduces a correlative microscopy approach for the detection and documentation of fossil pollen, while enabling a higher sample throughput. A1MM integrates scanning electron microscopy (SEM), light microscopy (LM) and fluorescence microscopy (FM) with optional downstream Airyscan imaging. Combining SEM, LM and FM imaging facilitates efficient detection and sufficient documentation of early angiosperm pollen as exemplified in material from Portugal (Barremian). SEM provides information on exine ornamentation, while LM and FM contribute complementary information on the grain’s overall morphology, aperture type and exine architecture. Subsequent Airyscan imaging may complement the obtained information with insights on the pollen wall ultrastructure. Permanently mounted material on microscope slides preserves the spatial context of the pollen and produces a permanent record of the specimen for potential typification of new taxa. The A1MM workflow is designed to produce correlative and complementary information on the pollen grains. The digital dataset of complementary visualization techniques enables morphological comparison and taxonomic revision. Datasets generated with A1MM may contribute to emerging digital palynology approaches and may bridge these with traditional LM and SEM approaches.

As components of modern forest ecosystems, woody angiosperms are the legacy of a complex evolutionary history rooted in the Cretaceous. To understand how woody angiosperms rose to global dominance from the Early Cretaceous to the Santonian, we analyzed their fossil wood record based on an exhaustive literature review, focusing on the paleodistribution and regional composition of angiosperm fossil wood. The first records of angiosperm fossil wood date back to the Aptian–Albian. During these stages, woody angiosperms achieved a global distribution and crown groups, such as fabids (Euphorbiaceae), malvids (Anacardiaceae), asterids (Theaceae), and lamiids (Icacinaceae), were present in temperate, subtropical, and tropical regions. A shift occurred during the Santonian marked by an increase in taxonomic diversity, notably within the fabids and malvids in tropical and subtropical climates. Although magnoliids and ANA-grade taxa were distributed at high latitudes, such as Antarctica, during the Santonian, asterids remained concentrated near the Equator. By the end-Cretaceous, woody angiosperms were established across diverse biomes, ranging from temperate to tropical regions. The absence of records in steppe and arid regions may reflect taphonomic and sampling biases rather than an absence of woody angiosperms in these regions. However, this pattern may also suggest that woody angiosperms had not yet emerged or expanded there. We propose that the mid-Cretaceous expansion of humid environments, together with a rise in wildfire frequency created new ecological opportunities for the diversification of woody angiosperms. By exploiting these newly available niches, woody angiosperms may have outcompeted established gymnosperm lineages.

This project investigates the interplay between climate forcing and ecosystem response during Middle Eocene hyperthermal events (48–47 Ma), brief periods of rapid warming with major carbon cycle and biological changes. These events offer insight into climate sensitivity and biological adaptation for evaluating future scenarios. The study is structured around two complementary components. First, we aim to reconstruct the background climate conditions of the hyperthermals by using the Messel Pit (a UNESCO World Heritage site in Germany) as a terrestrial archive, relying on stomatal density measurements and the application of a gas exchange model to fossil plants (Konrad et al., 2008). While GDGT-based temperature reconstructions are already available for Messel, independent constraints on atmospheric CO₂ are lacking. To address this, based on published protocols (Harper et al., 2024), we will generate a high-resolution CO₂ curve from boron-isotope (δ¹¹B) analyses of foraminifera from ODP Site 1263, which represents a marine counterpart to the Messel sequence. Second, we will assess the biological response of plants to these climatic perturbations. A systematic morphometric analysis of Messel fossil plants will be used to track adaptive changes and evaluate how plant functional traits responded to changes in CO₂ concentrations. By integrating marine geochemistry with terrestrial palaeobotany, this multi-proxy approach will provide a more complete picture of the environmental context and biotic responses during Eocene hyperthermals.

Eastern Australia was subjected to extensive intraplate volcanism throughout the Cenozoic and lava fields and volcanoes attest to our volcanic past. Floras buried by volcaniclastics include autochthonous elements, e.g. carbonised wood and roots in basalt flows, trees buried by ash falls and floras buried by volcanic activity. Transported leaves and branches occur as dispersed foliage in high energy ash flows (lahars) and pyroclastics or as dispersed leaves and fruits in lacustrine sediments in lakes and other depositional environments. Weathering of volcaniclastics releases silica resulting in the development of silcretes. These sub-basaltic silcretes are autochthonous assemblages consisting of palaeosols, leaf litter, ground-dwelling ferns, soil horizons and roots. The acidic (humic) and anoxic conditions provide ideal geochemical conditions for the deposition of silica and subsequent permineralization of plant remains. Soft tissue preservation of exocarps of fruits, actively growing vegetative shoots (fern croziers), bark of trees, roots and root nodules indicate burial by volcaniclastic sediments was rapid. The remarkable preservation of these plants provides the opportunity for high resolution studies of their plant anatomy. The autochthonous floras that occur in these sub-basaltic silcretes in eastern Australia are therefore discrete ‘time capsules’ of the local vegetation growing at that site at that time. These floras, however, remain little studied and represent a completely new set of data to understand the vegetation history of Australia. I will use our current work on the Melastomataceae, Casuarinaceae, Proteaceae and Pteridaceae to highlight some of the challenges in studying and interpreting these new floras.

The diversification of epiphytic and climbing plants during the late Paleozoic has commonly been linked to the development of densely vegetated swamp forests dominated by marattialean tree ferns that formed relatively closed canopies. Within the early Permian Wuda Tuff Flora, the zygopterid fern Nemejcopteris haiwangii was previously interpreted as a ground-cover plant characterized by a rhizomatous stem and upright phyllophores bearing primary pinnae arranged perpendicular to the frond plane. Although hook-like prickles on its axes had been suggested to aid climbing, unequivocal fossil evidence supporting such a growth habit has remained unavailable. Here we report several exceptionally preserved specimens that document direct physical associations between the fronds of N. haiwangii and trunks of Psaronius, demonstrating that this fern used tree hosts for climbing support. The prickles distributed along the axes indicate a hook-assisted climbing mechanism; however, their limited size and rigidity suggest that the species possessed only weak climbing capabilities and was probably unable to ascend into the upper canopy. Considering the sedimentological and ecological setting of the peat-forming swamp environment, we infer that the evolution of climbing in N. haiwangii may have represented an adaptation to periodic submergence rather than a strategy primarily driven by light competition. This interpretation provides an alternative explanation for the remarkable abundance and diversity of climbing plants in late Paleozoic coal-swamp ecosystems.

The Eastern Himalayan region of Sikkim preserves Gondwana-equivalent sediments exposed within tectonic windows and unconformably overlain by older lithological units. Owing to thrust-related deformation and limited preservation, both mega- and microfossil records are sparse. Early reports of the Glossopteris-Gangamopteris flora were provided by Hooker (1854), Mallet (1874), Acharya et al. (1979), and Singh (1990). However, these studies documented only a few species and lacked detailed morphotaxonomic analyses, leaving the floral diversity and precise age of the succession poorly constrained. Existing palynological data broadly assign the strata to the Damuda-equivalent succession (Late Sakmarian-Early Wordian).

The present study investigates the Gondwana flora exposed along the Nayabazar-Legship road section, Sikkim, to refine its floristic composition, biostratigraphic age, and palaeoecological significance. Megafossils are preserved mainly as impressions and are commonly weathered or deformed, obscuring diagnostic characters. The assemblage is dominated by Glossopteris, Gangamopteris, Paracalamites, Vertebraria, and associated scale leaves, with small and reduced leaf forms being particularly abundant.

Palynological analysis yielded key marker taxa, including Scheuringipollenites barakarensis, S. maximus, Faunipollenites varius, F. singrauliensis, Parasaccites korbaensis, P. obscurus, Striatopodocarpites magnificus, and Indotriradites indicus. These taxa correlate the succession with the Barakar Formation of Peninsular India and indicate an Early Permian (Artinskian) age. The assemblage further suggests deposition under warm and humid climatic conditions. The co-occurrence of Glossopteris-Gangamopteris flora and Scheuringipollenites supports assignment to a Barakar-equivalent horizon of Late Artinskian age. This study enhances understanding of Eastern Himalayan palaeobotany through improved documentation of morphotaxonomic diversity, biostratigraphy, and palaeoecology of extra-peninsular Gondwana floras.

We report several cases of upright permineralized stumps and in situ fossil forests preserved in felsic volcanic ash or reworked volcanigenic sediments in upper Permian strata exposed in coastal outcrops of the high-palaeolatitude Sydney Basin, Australia. The stumps are rooted in coal seams and are associated with transported logs and organic debris. Adpression floras in associated fluvial strata host low-diversity macrofloras of glossopterid gymnosperms and various herbaceous sphenopsids and ferns. Although preservational quality of the woods is variable, secondary xylem characters are consistent with glossopterid wood anatomy reported from other regions. Ring characters indicate growth under strongly seasonal conditions. However, intraseasonal perturbations to wood production were common, possibly induced by episodic ash falls and herbivore/pathogen attack. Individual forest horizons contain different stump size profiles suggesting a range of forest maturities are represented. Any one in situ stump horizon should not be considered representative of all Gondwanan Permian forests. In general, glossopterid forests appear to have had characters broadly similar in stature to modern boreal forested mires, with tree densities of over 1300 trunks ha-1. Multiple intercalated coal and tuff beds hosting upright stumps in individual stratigraphic sections indicate repeated burial events and recolonization of the land surface by forested mire vegetation on decadal to centennial time scales. As in modern boreal forests of volcanically active regions, such as the Kamchatka Peninsula, ash falls appear to have provided little impediment to the survival and persistence of the glossopterid coal-forming vegetation through the Guadalupian to Lopingian in humid high-latitude southeastern Gondwana.

The Paleocene–Eocene Thermal Maximum (PETM; ~56 Ma) represents one of the most rapid global warming events of the Cenozoic, yet terrestrial ecosystem responses in Central Asia remain poorly constrained. Here, we present a quantitative palynological record from the Xining Basin (northeastern Tibetan Plateau), spanning the late Paleocene to early Eocene, to reconstruct vegetation and climate dynamics across the PETM. Late Paleocene assemblages are dominated by xerophytic steppe-desert taxa, indicating arid conditions within the basin, while the signal from surrounding highlands suggests the presence of relatively warmer and more humid vegetation. At the onset of the PETM, these arid-adapted taxa rapidly decline and are replaced by temperate broadleaved species, accompanied by increases in pteridophytes and other angiosperms. This shift indicates a transition to markedly warmer and more humid conditions, likely driven by intensified monsoonal precipitation. During the early Eocene, vegetation partially returns to more mixed assemblages, with some areas showing signs of renewed drying while others remain relatively humid. Our results point to a pronounced regional increase in humidity during the PETM and early Eocene, contrasting with model simulations that predict drier conditions in subtropical regions. This discrepancy highlights the importance of regional controls on hydrological responses to global warming and underscores the value of terrestrial proxy records from Central Asia for improving paleoclimate reconstructions.

A new group of early land plants, the Eophytidae (eophytes), was recently proposed. It is based on specimens exceptionally preserved by charcoalification from the late Silurian (Pridoli) Ludford Lane and Early Devonian (Lochkovian) North Brown Clee Hill Lagerstätten. One of the chief characteristics of eophytes is that they produced cryptospores. Taxa with in situ spores contain either permanent dyads or tetrads, including both naked or envelope enclosed forms. Co-occurring plants produced trilete spores and are grouped with the protracheophytes or tracheophytes (‘rhyniophytes’). When originally proposed the eophytes were considered to be sister group to the polysporangiophytes (protracheophytes + tracheophytes). However, it seems more likely, based on cryptospore distribution, that they are the basal most stem group land plants (embryophytes) and are sister group to all other land plants (bryophytes + tracheophytes). In this talk I will discuss the reasoning behind placing the eophytes as stem group embryophytes and introduce a new taxon of eophyte.

The Battery Point Formation, exposed in eastern Quebec (Canada), hosts mid- to late Emsian fossil assemblages preserved as adpressions and permineralizations. At least 17 euphyllophyte taxa are known to date from permineralizations in this unit. We add to these five new euphyllophyte morphotypes described from permineralizations. Three of the five have Psilophyton-type tracheids typical of early euphyllophytes: one morphotype with a trilobed mesarch actinostele; a second morphotype with elliptical xylem (in cross section) and 2-3 mesarch protoxylem strands; a third morphotype with elongate xylem with lobed ends and probably mesarch protoxylem. The other two morphotypes have tracheids with circular-oval bordered pits indicative of cladoxylopsid affinities. One of them has an actinostele with three major ribs, two of which are bisected, and probably exarch xylem maturation, reminiscent of cladoxylopsid roots. The other is a larger cladoxylopsid with a typical deeply lobed and dissected actinostele-plectostele with multiple protoxylem strands per xylem lobe. These new morphotypes increase the taxonomic diversity and morphological disparity of euphyllophytes known from the Battery Point Formation. The group appeared in the late Silurian >425 Ma ago but euphyllophyte diversity remained modest during the first 15 million-years and increased significantly in the second half of the Early Devonian. Euphyllophyte diversity in the Battery Point Formation, unparalleled in coeval and older Devonian localities, provides the oldest snapshot of the effects of the first major radiation of the clade, suggesting that this early burst of diversification was fast and had probably started by the beginning of the Emsian.

Dispersed spore and pollen assemblages come from 134 boreholes drilled in the Kladno-Rakovník Basin, Czech Republic. The stratigraphic position of the Lubná group of coals, a member of the Radnice Formation, is Bolsovian (Moscovian). The assemblages consist of 167 species belonging to 53 genera. All three Lubná coal seams (Lower, Middle and Upper) represent different types of environment as documented by the palynological record. The oldest environment of the Lower Lubná group of coals is characterized by a raised ombrotrophic bog with dominance of Densosporites, spores produced by sub-arborescent lycopsids of the genus Omphalophloios. The Middle Lubná group of coals with prevalence of Lycospora, produced by the arborescent lycopsid Lepidodendron, is characteristic of a rheotrophic low-lying bog. The environment that formed the younger Upper Lubná group of coals was different, with a dominance of spores (smallest monoletes) from arborescent marattialeans. Palynology provides thus evidence of three distinct ecological environments that formed the three Lubná coal seams within ca 4 Myr (309 to 305 Myr).

The intra-continental Saar-Nahe basin formed in a half-graben structure during the variscan orogeny recording 40 mio years in 6500m of Carboniferous to Permian deposits.
Large scale coal formation occurred in the Westphalian and Stephanian stages of the upper Carboniferous. Excellent preservation of plant fossils focused interest on the floras since the 19th century with emphasis on taxonomical classification.

The completeness of the upper Carboniferous sequence and the abundance of macrofossils also allow for a detailed reconstruction of the vegetation succession throughout the major environmental changes that occurred towards the Permian.

Here we present six floras from the center of the Saar-Nahe basin located in the vicinity of Saarbrucken. Overall, the flora assemblages are characterized by lycopsids, filicopsids, pteridosperms, sphenopsids and cordaites. In the stratigraphic succession, the dominance of the various groups significantly changes where especially the loss of lycopsids and the increase in pteridosperms and cordaites in the Stephanian reflects the intensifying global drought towards the Permian. Interestingly, higher lycophyte abundance is observed in the youngest flora, which may relate to more local geomorphological and environmental conditions within the basin.

With a temporal resolution of less than 10 mio years between the floras and the highly regional representation of the upper Carboniferous, this study advances our understanding of the climatic changes associated with the large scale tectonic reorganization during the late Paleozoic.

Atmospheric CO2 and drought are key parameters of climate change. Both have profound impact on plant performance and therewith on both the carbon and hydrological cycle. Analysis of stable carbon isotope ratios in plant tissues is a common methods to determine ecophysiological responses as this data can provide information about a plant’s photosynthetic activity throughout its life.

Here, we investigate plant response and interaction of ancient lineages including lycophytes, sphenopsids and cordiatales, which have evolved under vastly different climatic conditions and persisted through several shifts major shifts in global climate. To test adaptation, we analyze δ13C values of well-preserved upper Carboniferous plant fossils from the Saar-Nahe basin (Germany). Here multiple sites with contrasting habitat ecologies are available that allow to elaborate on the potential wet/dry tolerance of individual plant taxa. For the sphenopsids, we moreover provide selected supplementary data from the Mesozoic and Cenozoic as well as historical herbarium specimen and modern representatives of Equisetum. Results of fossil and (sub-)modern δ13C values are compared to further evaluate the effects of increasing drought in combination with changing atmospheric CO2 on the general performance and photosynthetic potential of ancient plant lineages, with a focus on horsetails.

The Late Palaeozoic Ice Age (LPIA) was the Earth’s most intense Phanerozoic glacial event, now seen as a dynamic succession of glacial and nonglacial intervals during Carboniferous–Permian times. It has been hypothesized that the LPIA is linked to a CO2 decline partly driven by the colonization and diversification of land plants. Based on a new comprehensive compendium of late Palaeozoic (middle Mississippian–Guadalupian) plant families, summarising key information for global vegetation patterns, and temporal variations of floras due to palaeogeography, we have recently characterised the Palaeophytic–Mesophytic transition using a series of diversity rate metrics and multivariate analyses, including network analysis. The observed pattern of global biodiversity changes of vegetation has been related to LPIA glacial and nonglacial phases, as well as latitudinal and tectonically driven landscape changes. In this communication, new analyses show the impact of palaeogeography on this late Palaeozoic vegetation transition. Thanks to recent palaeoclimatic and palaeogeographical models, vegetation changes have been reconstructed within the main plant palaeokingdoms (phytochoria), i.e., Euramerica, Cathaysia, Angara and Gondwana, providing a new comparative framework. Results reveal highly palaeogeographical-based dynamics of heterogeneous changes from the late Palaeozoic coal swamps. For instance, while Pennsylvanian tropical wetlands in Euramerica collapsed, the early Permian swamps in high latitudes such as Angara and Gondwana underwent a great expansion. Importantly, results further reveal a major diversification pattern of tropical Cathaysian floras during the Permian similar to the observed diversification in higher latitudes. It supports phytogeography plays a crucial role in our understanding of floristic changes through time.

Among the seven families and ca. 4,000 living species of Laurales, unisexuality appears to have evolved multiple times across the order. To better understand the various pathways driving the evolution of sexual systems, the full morphological diversity of unisexual flowers and their associated sexual systems (e.g., monoecy vs dioecy) must be considered. Here, we reconstruct the evolution of sexual systems in Laurales using an undated and a new tip-dated phylogeny. We conducted Bayesian phylogenetic analyses using a morphological dataset of 62 floral characters that sampled 28 fossil flowers and 193 extant taxa of Laurales. To reconstruct the evolution of sexual systems, we tested four different character state transition models based on previous hypotheses of evolutionary transitions between sexual systems. Stochastic character mapping under the best-scoring model was used to reconstruct evolutionary transitions along the phylogeny. While phylogenetic placements of most Cretaceous fossil flowers differed between the undated and tip-dated analyses, results were robust between the two topologies when reconstructing sexual system evolution. Transitions to dioecy primarily occurred through two pathways: 1) direct transition from hermaphroditism to dioecy with structurally perfect and functionally unisexual flowers or 2) with an intermediate transition from hermaphroditism to monoecy with imperfect flowers before a transition to dioecy with imperfect flowers. Reversals to hermaphroditism were rare while reversals from dioecy to monoecy with imperfect flowers were frequently inferred. Our results indicate that Laurales has undergone numerous independent transitions to unisexuality through multiple pathways, suggesting that different molecular and evolutionary mechanisms have driven some of these transitions.

The Normapolles complex is one of the most distinctive and enigmatic elements of the Late Cretaceous. To date, thirteen genera of mesofossil flowers and fruits associated with this taxonomic complex have been identified. However, our understanding of the organization and architectural arrangement of these reproductive structures within inflorescences remains limited.

Here, we report a new Normapolles taxon based on well-preserved fossil flowers, fruits, and inflorescences from the Klikov Formation. They are linked by the abundant occurrence of the same type of pollen adhering to their surfaces. The fossils were investigated with SEM and X-ray tomography and are described as a new extinct taxon.

The flowers are arranged in compound dichasia, each unit composed of one central bisexual flower terminating the primary inflorescence axis, two lateral bisexual flowers terminating the secondary inflorescence axes and four peripheral pistillate flowers, two on each secondary axis in lateral position. All flowers are sessile, disymmetric, dimerous, and epigynous with two whorls of two tepals each. Bisexual flowers have four stamens with long, narrow filaments. The gynoecium is bicarpellate and syncarpous with a partially inferior and unilocular ovary. The fruit is a one-seed nut.

Multiple, well-preserved specimens provide detailed morphological information on the inflorescences, flowers, fruits, and seeds across different developmental stages. The combination of characters shows potential affinities with representatives of several fagalean lineages, particularly Betulaceae and Juglandaceae. This finding further expands our understanding of the diversity of the Normapolles complex during the Late Cretaceous.

Needle-leaved conifer shoots are among the most abundant plant fossils found in the Upper Cretaceous sediments of southern Alberta, Canada, and typically are assigned to the subfamilies Taxodioideae or Sequoioideae (Cupressaceae sensu lato). Their taxonomic delineation, however, remains challenging due to the incompletely understood phenotypic plasticity of these taxa. Most Canadian Late Cretaceous ambers are thought to have been produced by cupressaceous trees of the fossil-genus ‘Parataxodium’ Arnold et Lowther based on amber inclusions and amber chemistry. This generic assignment is based solely on the amber inclusions, which are rare and incompletely preserved. Additionally, the taxonomy of the comparative material has been subject to a decades-long debate. We quantify the morphological variation of extant species of the Sequoioideae and Taxodioideae, the Grassy Lake amber inclusions, and the three-dimensional silicifications from the Horseshoe Canyon Formation originally used as comparative material for the amber inclusions. Furthermore, we compare the disparity between the fossils and extant species, and test for species delimitation. Our results show that extant taxa can be distinguished macromorphologically but the silicified shoots and amber fossils show greater variation, especially with regard to phyllotaxis. While the silicified fossils display remarkable stability in their micromorphology, allowing their delimitation, the amber inclusions displayed two distinct, hitherto overlooked, shoot morphologies assignable to Cupressaceae sensu lato. Combined with the lack of cuticular preservation, which prevents appropriate comparisons, these results invalidate an assignment of the amber inclusions to ‘Parataxodium’.

A diverse and well-preserved assemblage of ~163 spore–pollen taxa from a Cretaceous–Paleogene (K/Pg) boundary interval within the marginal-marine Oyster Bay Member of the Salish Formation (OBM), Vancouver Island, Canada, reveals an attenuated terrestrial floral response to the end-Cretaceous mass extinction. Local extirpation of ~15% of Cretaceous taxa contrasts with the substantially higher turnover documented from the Western Interior Basin (WIB) of North America. Latest Maastrichtian assemblages are dominated by fern, lycophyte, and bryophyte communities occupying humid coastal lowlands, whereas Danian palynofloras record a gradual reorganization toward conifer-dominated forests with a persistent fern understory and increasing representation of anemophilous angiosperms. Several characteristic K-taxa, including Liliacidites complexus, Tricolpites microreticulatus, Tschudypollis thalmanii, and Retibrevitricolporites beccus, persist above the boundary, demonstrating diachroneity between continental-margin and interior palynofloras. Unlike most North American K/Pg successions, the OBM lacks a distinct fern-spore spike; although Cyathidites and Laevigatosporites increase within the boundary interval, assemblages remain taxonomically rich and compositionally heterogeneous, indicating ecological resilience rather than ecosystem collapse and opportunistic fern proliferation. The palynoflora is characteristic of the Continental Margin floristic province and includes numerous endemic and long-ranging taxa that reflect paleogeographic isolation of the Georgia Basin. Persistent occurrences of palm pollen, including Arecipites spp., Spinizonocolpites spp. (aff. Nypa), and Pandaniidites typicus, indicate warm, humid, frost-free subtropical conditions. Collectively, these data suggest that maritime climatic buffering ameliorated the effects of the Chicxulub impact winter along the continental margin, fostering ecological stability and sustaining coastal refugia through the K/Pg transition.

Taxonomic databases and digital identification tools have become essential resources in palaeobotany. In wood anatomy, the InsideWood database gathers thousands of standardized descriptions and photographs with an identification key. Similarly, the Plant Fossil Names Registry provides comprehensive information on fossil plant taxa, including nomenclature, type specimens, stratigraphic and geographic distributions, and fossil category (e.g. wood, leaf, and fruit). In modern palynology, the Palynological Database (PalDat) offers detailed species-level descriptions, illustrations, and bibliographic references.

In contrast, sporomorph (pollen and spores) palaeopalynology still lacks comprehensive digital identification tools. Existing resources are generally limited to catalogues and do not integrate species-level diagnoses, descriptions, botanical affinities, stratigraphic ranges, and illustrations within an interactive identification framework comparable to InsideWood. The development of such a tool would considerably improve the efficiency and reproducibility of taxonomic identification, particularly for early-career palaeopalynologists (e.g. Bachelor’s, Master’s, and PhD students).

Here, we present a new identification key for Paleogene pollen and spores from Eurasia, with an initial focus on Türkiye. The key is hosted on the Xper3 platform. This first version includes 176 Turkish taxa (illustrated with light microscopy microphotographs) and 73 descriptors. Additionally, we provide a new set of anatomic diagrams for pollen and spores, which will be openly accessible. Our long-term goal is to progressively expand the database to achieve broader taxonomic coverage and to include additional regions and geological periods.

The Early Eocene Climatic Optimum (EECO; c.53–49 Ma) is one of Earth’s hottest times marked by high global temperatures that allowed forests similar to modern tropical regions to thrive within the polar circles. These polar ecosystems were subject to an extremely seasonal light regime and atmospheric CO2 levels vastly different to any modern forests. Although the taxonomic composition of many ancient polar floras is well established, their forest structure at high latitudes remains largely unresolved.

The fossil plant assemblage of the Macquarie Harbour Formation (53–50 Ma) in Tasmania, southeastern Australia, was situated near the south polar circle (65–70°S). While Tasmania represented the last land bridge between Australia and Antarctica, its flora likely expanded along Antarctica’s margin.

Recent excavations have resulted in hundreds of leaf compressions that received detailed systematic study, thus offering a window into the extinct southern polar forest biome. We utilise this flora to study the vertical and horizontal forest structure (stratification, canopy openness) by using geochemical and morphological proxies for canopy structure as well as additional lines of evidence from systematic studies. We present the first results and methodological approaches to characterise this vegetation within the southern polar forest biome.

The western Amazon was extensively influenced by marine incursions. This is evident from the fossil record, which includes mangrove pollen, dinoflagellate cysts and microforaminiferal organic linings. Rhizophoraceae were common, but also Florschuetzia-type pollen were observed in cored sediments from westernmost Brazil. Here we investigate whether sonneratioid mangroves of Southeast (SE) Asian origin extended into the Amazon. To do this, we revisited the Brazilian core 1AS-4a-AM and applied light and scanning electron microscopy (LM and SEM) to selected sporomorphs. We also revised the temporal range of Florschuetzia occurrences and reassessed the morphological description of Florschuetzia impostora by applying confocal microscopy. Based on this study, we amend and extend the description of F. impostora (D’Apolito et al. 2021) and present a new species: Florschuetzia amazonica sp. nov.. Both species strongly resemble F. trilobata and F. ovalis, described from SE Asia, but their specific morphological traits, disjunct distribution and short-spanned abundant occurrences differentiate them. In the Amazon, Florschuetzia mangroves were associated with a high abundance of palms and mangrove-associated ferns, suggesting it occurred in the back-mangrove zone, landward of the Rhizophoraceae belt. We conclude that Early Miocene (or older) dispersal events from South East Asia contributed to a richer and more complex mangrove ecosystem in northern South America than is seen today.

When ecosystems are devastated by environmental crises and mass extinction events, recovery is rarely immediate. Instead, the first plants to reclaim these disrupted landscapes are often hardy opportunists that establish short-lived pioneer communities before more complex forests can return. We show that a similar ecological response followed the end-Triassic mass extinction, approximately 201 million years ago.

We show that the extinction of ‘seed-ferns’, such as Lepidopteris, was followed by a short-lived proliferation of sphenopsids (horsetail) and lycopsids (club mosses). New fossil discoveries from Lower Jurassic (Hettangian) deposits in Sweden record the last known appearance of the distinctive pleuromeian lycopsids. These fossils allow us to link the parent plant, Lycostrobus scottii, with both its large and small reproductive spores. Using occurrences of the characteristic megaspore Nathorstisporites hopliticus, we track the distribution of L. scottii across the critical interval spanning the Triassic–Jurassic transition and reconstruct its geographic and temporal history.

Our phylogenetic analyses identify Lycostrobus scottii as the youngest representative of the Pleuromeiaceae and recover this family as the sister group of the Chaloneriaceae. Taken together, the evidence suggests that pleuromeian lycopsids briefly flourished on a global scale in the wake of the end-Triassic ecological collapse. As Late Triassic forests disappeared, these resilient herbaceous plants rapidly spread into newly available habitats, forming widespread pioneer vegetation during the earliest Jurassic.

The Triassic-Jurassic (T-J) boundary saw global ecological upheaval driven by volcanism, with extremely elevated atmospheric CO2 (>2000 ppm) and temperatures (GMST >24°C). Extensive community turnover and desertification are accompanied by directional changes in heat avoidance leaf traits. We explore the interaction of traits, constrained by fossils (paleo-traits: leaf width (w), maximum stomatal conductance (gs,max) and xylem vulnerability to cavitation-induced embolism (ΨC)) and simulated paleo-climate (HadCM-3B) using a process-based ecosystem model (paleo-BGC). We test whether trait coordination (1) limits forest cover and (2) results in the same pattern of community turnover observed at two well-studied T-J sites.

Simulations reveal that the order of magnitude reduction in leaf size conferred extensive biogeographic and metabolic advantages for taxa with small leaves.
Slowed plant water use due to aridity and changes in stomatal anatomy reinforced the need for other modes of heat avoidance. Simulated maximum T-J leaf temperatures at several CO2 levels are compared to leaf thermal tolerance and acclimation from neo-botany.

Our process-based simulations connect fossil evidence to mechanisms of plant survival known from modern ecosystems to better understand paleo-ecosystems. At the same time the fossil record can increasingly inform better vegetation projections under anthropogenic CO2 emissions scenarios, and clarify our future.

The Early–Middle Jurassic represents a key greenhouse interval marked by major environmental perturbations associated with the Karoo–Ferrar Large Igneous Province events (K–FLIPs) and the Pliensbachian–Toarcian boundary event. Although marine records have documented coupled carbon- and mercury-cycle disturbances during this interval, their expression in terrestrial ecosystems remains less well constrained.

Here, we present a plant-based, multi-proxy dataset derived from fossil ginkgo leaves collected from discrete stratigraphic horizons across an approximately 20-million-year interval in the Lower–Middle Jurassic succession of the Qaidam Basin, China. Fossil leaves were analysed for leaf morphology, stomatal characteristics, total organic carbon (TOC), carbon isotope composition (δ¹³C), atmospheric CO₂ reconstructed using a leaf gas-exchange model, and mercury (Hg) concentrations.

The results reveal stratigraphically coherent variations in δ¹³C values, Hg concentrations, and reconstructed atmospheric CO₂ across the studied interval. Intervals characterized by more negative δ¹³C values are commonly associated with elevated Hg concentrations and higher reconstructed CO₂ levels, whereas intervals with less negative δ¹³C values generally show lower Hg concentrations and lower reconstructed CO₂. Although alternative processes, including wildfire activity, cannot be entirely excluded, the observed coupling between carbon-isotope shifts, Hg enrichment, and reconstructed CO₂ is consistent with large-scale volcanic activity contributing to simultaneous perturbations of the carbon and mercury cycles.

These findings provide terrestrial plant-based evidence for coupled biogeochemical-cycle perturbations during an Early–Middle Jurassic greenhouse interval. More broadly, they highlight the value of fossil leaves as integrated archives for reconstructing atmospheric composition, mercury loading, and ecosystem-scale responses to extreme environmental events in deep time.

The present study documents a macrofloral assemblage from Eriksdal in southern Sweden. The assemblage includes leaves, seeds, pollen-bearing microsporangia, wood, roots and is complemented by palynological and sedimentological analyses to provide a comprehensive paleoenvironmental reconstruction of the site. Our results indicate forests dominated by ginkgophytes and mixed-conifers (cypress, cheirolepids, araucarias) with ferns as understory components. Of particular significance is the identification of a leaf bed interpreted as an autumn fall of ginkgo foliage, associated with seeds exhibiting preservation of organic seed coat tissue. UV fluorescence microscopy and SEM were employed for characterization of selected macrofloral remains. Integrated sedimentological and palaeobotanical data indicate that this plant assemblage developed in a floodplain under warm and humid climatic conditions during the Bajocian. These findings advance our understanding of past terrestrial ecosystems in southern Scandinavia, offering a deep-time perspective on vegetation–climate interactions in Northern Europe.

Furthermore, drawing upon principles of paleophysiology, we present a comparative analysis of stomatal responses between several extant plants cultivated under experimentally elevated CO2 concentrations and their ancient Mesozoic relatives. Specifically, fossilized leaves of Ginkgoites regnelli from Eriksdal were examined and compared with those of extant Ginkgo biloba grown under elevated CO2 regimes designed to mimic Mesozoic atmospheric conditions. Through this innovative approach, we aim to provide insights into stomatal physiology, which constitutes the current base of several paleoatmospheric CO2 proxies

Noeggerathiales are an extinct group of plants that existed during the Late Palaeozoic, with approximately 20 genera and 97 species reported to date. Although their first description dates back more than 200 years, the research on the phylogenetic relationships among the various genera within this order remains limited, and Noeggerathiales have only recently been assigned to the progymnosperms based on the reconstructed whole-plant Paratingia wuhaia. Owing to preservation biases and the uniqueness of their morphological characters, it remains unclear whether all reported genera and species represent a single natural taxonomic group. In the present review, the temporal and geographical distribution of the fossil record of Noeggerathiales is summarized, and a phylogenetic analysis is conducted based on currently available fossil data. With respect to the chronostratigraphic distribution of foliage organs, Noeggerathiales may have first appeared in the Euramerican floral realm, later gradually extended to other regions of that realm, subsequently migrated to the Cathaysian floral realm, and flourished there until the end of the Permian. Phylogenetic analysis supports a close relationship of all known noeggerathialeans to progymnosperms, although they are mainly known from partial organs rather than whole-plant reconstructions.

Tree ferns dominated the tropical and subtropical forest canopies of the late Carboniferous to early Permian, most belonging to the eusporangiate order Marattiales. However, most Paleozoic tree fern fossils are preserved as isolated organs, such as fragmented pinnae or petrified rachis segments, thereby limiting integrated morphological and anatomical studies. The early Permian Wuda Tuff Flora of Inner Mongolia, China, a T0 fossil Lagerstätte known as the “vegetational Pompeii”, has yielded abundant tree fern fossils, including numerous organically connected specimens bearing both fertile and vegetative organs. Here we describe a new tree fern genus based on such specimens from the Wuda Tuff Flora. The type species possesses tripinnate fronds with pecopterid pinnae. Petioles and pinnae axes bear unicellular trichomes and contain endarch, C-shaped vascular bundles with two laterally involute to revolute ends, representing the stewartiopterid-type configuration characteristic of Marattiales. Fertile pinnae occur on the lower part of fronds, with strongly contracted pinnule laminae. Synangia comprise four sporangia attached to the midvein by a short pedicel, differing from all previously reported marattialean synangia, which are typically borne on lateral veins. Sporangial walls are uniseriate and lack an annulus. Spores are trilete, microechinate, 13–20 μm in diameter. This new genus integrates classic marattialean anatomical features with a leptosporangiate-like uniseriate sporangial wall, representing a mosaic of character states indicative of a transitional lineage. This discovery significantly expands early Permian tree fern diversity and provides crucial evidence for understanding the evolutionary dynamics and morphological innovation among Paleozoic ferns.
Key words: Marattiales, synangium, diversity, transitional lineage

Highly allochthonous plant megafossil assemblages from Bearreraig, Skye, offer a rare opportunity to study the well preserved anatomy of several Middle Jurassic tracheophytes. Deposited in fully marine stenohaline conditions offshore from multiple river discharges, the 14 plant-bearing horizons spanemphasized text ~110 m (5 MYr) of early Aalenian to early Bajocian strata. They have yielded ~16 disarticulated organ-species that represent a minimum of nine whole-plant species: one equisetalean (one pyritised axis), four filicalean ferns (frequent fusainised pinnae, occasional rachises), one cycad (rare permineralised leaves, seeds), one bennettite (rare permineralised leaves), and at least two conifers (common permineralised leafy shoots, insect-bored woody axes, wood fragments; rare cones). Calcitic nodules enclosing the plant megafossils also contain diverse assemblages of well preserved miospores (dominantly bisaccates), and representatives of many major groups of contemporaneous marine biota, collectively establishing Bearreraig as the reserve Aalenian–Bajocian stratotype. Detailed palaeobotanical descriptions of permineralised organs have thus far encompassed the two cycadophyte leaves (Nilssonia tenuinervis, Otozamites mortonii) and two coniferous ovulate cones belonging to new genera of Cupressaceae that were subjected to XRT examination. Scitistrobus duncaanensis is assigned to subfamily Cunninghamioideae, whereas Pyrostrobus gerontostorros – the subject of ongoing research – is tentatively assigned as a stem-group to the more derived subfamily Sequoioideae, constituting by far its earliest known member. Both cones exhibit charred exteriors and the accompanying fern fossils are reliably fusainised, suggesting that periodic wildfires caused low-temperature crown-fires in an open coniferous forest while wholly consuming the fern-dominated understorey.

Out of the seed plants of the Mesozoic, the order Ginkgoales stands out due to a combination of several factors. Not only were they present from the beginning of Triassic until the K/Pg mass extinction, but their geographic range was also global with remains having been found on all continents (including Antarctica). Perhaps most importantly, however, a single species -Gingko biloba- has weathered the tides of extinction, enduring into the present and providing us with a unique opportunity to witness a fraction of the diversity that the order once had. Yet, this lone survivor creates additional challenges to our understanding of the evolution of the group. The morphological variability of the leaves of this single species is considerable, and often exceeds the variability used to distinguish between different extinct species.

In order to gain insight on how much of the diversity in the fossil record may be a result of intraspecific variability, we tried to quantify the variability present within the extant species to then compare it with what observed within single fossil localities and species. To achieve this, we measured the shape over 500 leaves from living Ginkgo trees from around the globe using topologic data analysis, TDA, a mathematical process that comprehensively quantifies the characteristics of the shape, making it possible to infer evolutionary/genetic distances between two individual specimen by there topologic similarity. This represents the first step to generate a large database of leaf shape including fossil Ginkgoales from across their temporal and spatial distribution.

When looking at Earth history, there are four recognisable durations where resin production and preservation were greatly enhanced. These were the (1) Late Triassic (Carnian), (2) Cretaceous, (3) Eocene, and (4) Oligo-Miocene amber bursts. The rather short Carnian amber burst has been linked to the major climatic upheaval of the Carnian Pluvial Episode and its consequences for the terrestrial realm. Recently, numerous different factors have been put forward to explain the Cretaceous Period’s extensive richness in amber deposits. In contrast, the two younger amber bursts had not yet not been subjected to the same level of investigation. Here, we examine the Eocene amber burst in depth. During this ice-free epoch numerous deposits, including the largest in the world (Baltic amber), were formed. To understand what might underlie this resinous interval, we created a carefully scrutinised and curated database of 62 Eocene amber deposits in total, with many others having to be excluded on various grounds. We also collected additional geological and biological information on each in order to assess their depositional settings. We highlight issues that affect inferring large-scale dynamics or triggers such as potential prospecting and collection biases, and sometimes poor availability of dating and/or sedimentological information. Despite these issues, we show extensive distribution of amber deposits across most of the world, and through the whole of the Eocene, not linked to any particular climate event.

The Paleogene was marked by a sudden rise in temperatures, which peaked during the Paleocene–Eocene transition and was followed by a climatic optimum during the early and middle Eocene. In the Paris Basin, the presence of palm trees (Arecaceae) in the fossil record has been documented since 1810. Numerous palm leaves, fruits, stems, and pollen grains have been described over the last 200 years. Recently, new palm stems, fruits, and seeds were discovered at the Rivecourt (Thanetian) and Le Quesnoy (Ypresian) sites in the Oise region. The aim of this study is to describe the evolution of palm trees in the Paris Basin during the Paleogene through re-examination of the fossil record combined with new discoveries. Studies of fruits, seeds, and stems revealed the presence of the genera Phoenix, Sabal, and Oncosperma as early as the Paleocene. These genera are also recorded throughout the Ypresian climatic optimum based on pollen, leaves, fruits, and seeds, before declining later, probably as a result of climatic deterioration at the Eocene–Oligocene transition. The genus Nypa first appeared during the Ypresian and persisted through the Lutetian, as evidenced by fruit and pollen records. Altogether, the Arecaceae provide evidence for the persistence of a relatively stable tropical flora in the Paris Basin for nearly 15 million years, as well as for the continued presence of mangroves during the Eocene. Today, these genera occur in tropical and subtropical floras of Asia and the Americas, reflecting the complex biogeographic history of the palm family.

The Eocene collision of Indo-Pakistan into Asia and resulting biotic exchanges contributed to the immense biodiversity of tropical Asia. However, paleobotanical data with robust age controls from pre-interchange Indo-Pakistan are rare, limiting constraints for testing these hypotheses. Previously, mammal assemblages from the early Eocene (ca. 54–50 Ma) Ghazij Formation in Balochistan, Pakistan showed an into-India dispersal pattern. Here, we report the first plant macrofossils, insect damage, and comprehensive palynological data from the Ghazij Formation. The palynofloras indicate an environmental transition from coastal marine settings (lower Ghazij), to freshwater and coastal palm swamps (middle Ghazij), and to increasingly terrestrial ecosystems with persistent marine influence (upper Ghazij). We found palynomorphs typical of modern Southeast Asian forests in the lower and middle Ghazij, an interval of negligible mammalian interchange with Asia, including Podocarpus, Dacrydium, Casuarinaceae, Nypa, Barringtonia, Dipterocarpaceae, and Alangium. Additional pollen taxa from the upper Ghazij include Croton, Malvaceae, Polygonaceae, and Onagraceae. The macroflora is dominated by leaflets similar to Pometia (Sapindaceae), found throughout the Asian tropics today, and multiple Fabaceae and Arecaceae morphotypes. Rarer morphotypes include possible Menispermaceae, Rhamnaceae, Araceae, and the ferns Acrostichum and Salvinia. Insect-feeding damage is diverse and abundant, totaling 42 damage types—some of the highest richness of insect herbivory in the fossil record, when adjusted for sample size. Our finding of several extant Southeast Asian taxa as palynomorphs in the pre-collision lower and middle Ghazij is consistent with established hypotheses. However, pre-collision palynofloras from Southeast Asia are too sparse to entirely rule out a prior presence.

The study of plant-insect interactions in the fossil record is one of particular significance, as it not only gives us a better understanding of the evolution of such relations, through time and space, but also provides information on how said interactions, and by extension the wider ecosystem, reacted to ancient global changes. The Paleocene-Eocene Thermal Maximum (PETM) is major but brief environmental crisis that drastically reduced the diversity of plant-insect interactions, at least in North America. Recent studies in other parts of the world, such as South America and Europe, suggested that these effects might have been more regionalised than previously assumed, but the picture is far from clear in Europe, where early Eocene data are sparse.

In this study, we describe the diversity of plant-insect interactions in the Ypresian assemblage of Monte Bolca, in Northern Italy. We then compare these interaction patterns to those observed on older Paleocene assemblages (Gelinden in Belgium, Menat and Sézanne in France). These assemblages reveal a stark increase in interaction diversity following the Paleocene-Eocene boundary, mirroring what had been observed in North America at the same period, although with a much higher Paleocene diversity to start with in Europe. These results contrast with the reactions to the K/Pg extinction, which are far less pronounced in European floras. Finally, we also use this opportunity to generate new protocols to assess the effects of preservation bias in measuring plant-insect interactions, allowing fairer comparisons between assemblages.

The late middle Eocene, subpolar flora from Anglesea (Victoria) is a uniquely informative paleobotanical assemblage from terminal Gondwanan Australia, yet much of its diversity remains undescribed. Using light, fluorescence, and confocal microscopy, we re-examined Anglesea legacy collections (>2,000 organically preserved leaves and corresponding cuticle slides) housed at the Melbourne Museum and report four new angiosperm families in the flora: Dilleniaceae, Euphorbiaceae, Monimiaceae, and Atherospermataceae; and one new conifer genus, Acmopyle (Podocarpaceae). The Dilleniaceae leaves have random reticulate tertiaries, glandular teeth, and brachyparacytic stomata, placing them in the Neotropical subfamily Doliocarpoideae. Euphorbiaceae are represented by one peltate leaf with teeth, disc-shaped scales, and sunken cyclocytic stomata, similar to the Old-World genus Macaranga. The Monimiaceae fossils have festooned semicraspedodromous secondaries, irregular glandular teeth, and brachyparacytic stomata, comparable to the Australasian genera Hedycarya and Wilkiea. The Atherospermataceae leaves have festooned semicraspedodromous secondaries and gland-tipped teeth; we recognize three new species: one of the Australian endemic Doryphora, with striated cuticle and stephanocytic stomata; one of Laurelia (New Zealand and southern South America), with strong secondary loops and stephanocytic bicyclic stomata; and one of an extinct genus, with irregular teeth and papillate cuticle. The tropical rainforest podocarp Acmopyle is represented by one leafy branch with bilaterally flattened leaves bearing hypoplastic stomata. Additionally, we observed accessory transfusion tissue in Podocarpus platyphyllum, providing direct anatomical evidence for an ever-wet ecosystem. These discoveries expand the diversity and biogeographic connections of the Anglesea flora and Paleogene Australia, emphasizing the conservation value of extant rainforests that preserve Gondwanan survivor lineages.

Extant Banksia, an iconic Australian genus, have a series of xeromorphic traits (sclerophyllous leaves and bark; sunken stomata; typically revolute or recurved leaf margins) and are primarily serotinous. Because they are well-adapted to the dry, fire-prone environments of modern Australia, their presence in the fossil record is often interpreted as an indication of seasonality or aridity (Hill, 1998; Carpenter et al., 2014). These interpretations often conflict with other lines of evidence, including sedimentology, for their occurrence in wet palaeoenvironments (Korasidis et al., 2019) or even other plants in the same assemblage (McCurry et al., 2022). This study investigates three Banksia species (B. angusta, B. cooksoniae, B. laevis) that are found co-occurring in a thin stratum within the large Middle Miocene (~15 my) Yallourn Coal Seam; part of the Gippsland Basin in Victoria, Australia. This layer has been designated the “Banksia layer,” because of the predominance of Banksia macrofossils. These three Banksia have distinct morphological features, indicating different life strategies and adaptations to the low-nutrient pedogenic conditions and frequent fires that plagued the emergent marsh ecosystem they inhabited. Seven infructescences recovered from Yallourn, have been CT-scanned, and related to their respective species. These three species are redescribed using their leaves, cuticles, and infructescences. By conducting a morphological comparison with extant Banksia, the nearest living relatives are identified for the three Yallourn Banksia, and their life strategies compared and evaluated from a palaeoenvironmental perspective. Having these species co-occurring in a water-logged, peatland environment invites further investigation of how Banksia evolved in Australia.

Plants could be considered as ‘living rocks’ based on their multi-elemental composition. They play a disproportionately important role in terrestrial biogeochemical cycling of elements compared with other living organisms, particularly at times of extreme environmental change such as mass extinction intervals. It is widely acknowledged that terrestrial plants are ecosystem engineers however considering their potential to alter soil and sedimentary profiles via the processes of weathering, decomposition and homeostais this paper will put forward the hypothesis that plants are lithosphere engineers or modulators of sedimentary profiles. Results from evolutionary decomposition and weathering experiments will be reviewed and integrated with new data on transcriptomic and plant elementome responses to extreme paleo-atmospheres experiments. These multidisciplinary data sets will be used to introduce the concept of the paleo-elementome for application to fossil plants and to hypothesize what the fossil plant paleo-elementome can tell us about plant mass extinction and terrestrial ecosystem collapse in the geological past.

The plant fossil record is naturally biased and quantifiable leaf traits vary greatly by preservation conditions. Like all living organisms, plant chemical composition consists of a suite of bioelements, essential for survival, homeostasis and competition. Here we extend the ‘biogeochemical niche’ and ‘elementome’ hypotheses to deep-time floras on the basis that stable isotopes of many elements are demonstrably unaltered in compression fossils.

To test this, we use well-established chemical analysis methods of herbaria, and, for a broad fossil application and replicability, we use both non-destructive and high-spatial precision methods: portable X-ray Fluorescence and Laser Ablation Inductively Coupled Plasma Mass Spectrometry. While many other studies report fossil leaf chemical compositions, none use a holistic multi-elemental approach, capturing all present and detectable elements.

Our study reports the multi-elemental composition of fossil leaves from the Jameson Land Basin, East Greenland, which span the end-Triassic mass extinction (ETME). To ensure sufficient replication, we used ecologically dominant taxa of five distinct morphogenera.

Our data indicate an observable elemental shift in taxa that are continuous through time (across the ETME) and highlight distinct compositional differences between taxonomic groups. The study demonstrates a regional-scale elemental profile independent of depositional setting and distinguishable from host rock; supporting detection of a fossil leaf ‘palaeo-elementome’. Coupling fossil plant palaeo-elementomics with ETME palaeoecological shifts in the Jameson Land flora, facilitates establishment of a novel plant chemical ecology method in the field of palaeobotany.

Increased occurrences of malformed spores and pollen during several of the mass extinctions of the Phanerozoic suggest that land plants plants were subjected to significant environmental stress during these crises. For the end-Triassic mass extinction, synchronicity between elevated concentrations of Hg in sedimentary successions and increased amounts and severity in malformations of fern spores suggest that Hg emitted from the Central Atlantic Magmatic Province contributed to mutations in ferns. Spores from extant plants growing in severely contaminated sites have previously been reported to contain elevated amounts of heavy metals, but it has not been clear where exactly the elements are situated in the spores; whether they are incorporated in the cells only, the walls only or both. In order to investigate whether traces of atmospheric pollution from large igneous province volcanism during the end-Triassic mass extinction is preserved in the fossil fern spores we used synchrotron Nano-XRF to analyse: 1) normal and mutated fossil fern spores from the Triassic-Jurassic boundary succession at Stenlille, Denmark; 2) extant spores from ferns grown on normal and Hg-contaminated soils in a laboratory setting; and 3) spores from a fern collected from a heavily polluted site in Slovakia. Our preliminary results have implications for how elements are differentiated in the spores and highlight the importance of element uptake pathways in fossil spores.

Malformed pteridophyte spores occur abundantly in conjunction with the end-Triassic mass-extinction (ETME), ~201.6 million years ago, one of the ‘Big Five’ mass-extinction events of the past 500 million years. Based on high concentrations of sedimentary mercury (Hg) in beds that contain abundant malformed spores, it has been hypothesized that volcanogenic Hg-emission from large-scale volcanism in the Central Atlantic Magmatic Province exerted stress on standing and pioneering vegetation, causing malfunctions in meiosis. Here, we provide strong evidence for anomalously high Hg among the plant survivors of the ETME using synchrotron X-ray fluorescence scanning of the earliest Jurassic fossil fern Phlebopteris angustiloba from southern Germany. P. angustiloba is a member of the Matoniaceae, which produced malformed spores within the Deltoidospora-Concavisporites complex that are common in the same beds that contain the fern fossils. Comparative XRF and XANES synchrotron-scanning of extant ferns growing in high-mercury environments in Slovenia, Slovakia, and the Czech Republic, suggest that ferns can tolerate elevated Hg-levels and store it in their placentas with the help of sulfurous compounds.

Leguminosae is a monophyletic family composed of ca. 19,000 species distributed worldwide and growing from deserts to wet tropical forests. The Leguminosae fossil record is relatively abundant and diverse, comprising leaflets, wood, fruits, flowers, and pollen. Nevertheless, this diversity – in particular when based on the leaf fossil record – should be interpreted with caution because distantly related extant Leguminosae species commonly show similar leaflet morphology resulting from convergent evolution. Here, we revise Oligocene leaflets from Southwest Europe (France and Spain) previously attributed to Mimosa and Mimosites and compare them with other Cenozoic European records to clarify their taxonomy. Several fossil-species were synonymized, and three new taxonomic combinations were established under the fossil-genus Parvileguminophyllum. Morphological comparison with extant legumes reveals affinities with Mimosa and Senegalia species thriving in seasonally dry tropical climates (Aw/As Köppen types). However, palaeoclimatic data from the localities in which the here studied Parvileguminophyllum species occurred indicate that the fossil-species grew in humid subtropical conditions (Cfa/Cwa). The results indicate that the Parvileguminophyllum fossil-species became extinct during the Miocene, a period marked by increasing global aridity. Our analyses suggest that cooler temperatures and more frequent frost events were the primary drivers of this extinction. This interpretation challenges the long-standing assumption that Paleogene leguminous fossil-species from South Europe reflected xeric environments and radiated during intervals of increasing aridity, a view that may stem from their morphological resemblance to extant taxa growing in arid environments.

Lake Sevan represents one of the most important freshwater ecosystems in the Caucasus region and serves as a unique center of biodiversity. Paleoenvironmental and palaeobotanical investigations from the Tsovinar-1 peat section reveal that Middle to Late Holocene lake-level fluctuations strongly influenced terrestrial and aquatic biodiversity in the region. Analyses of pollen, macro- and micro-plant remains, and fossil algae demonstrate that humid periods supported the development of forest vegetation, aquatic ecosystems, and extensive wetlands, whereas drier phases promoted the expansion of steppe communities and reduced aquatic habitats.

Pollen and carpological records document a diverse aquatic flora, including Nymphaea alba, Menyanthes trifoliata, Ceratophyllum, Potamogeton, and Myriophyllum, indicating a richer freshwater biodiversity than exists in the Sevan basin today. Fossil seeds of Menyanthes trifoliata and fruits of Ceratophyllum demersum var. platyacanthum, together with pollen of the relict tree Zelkova carpinifolia, confirm the former presence of these taxa in the region. However, these species are absent from the modern flora of the Lake Sevan basin, demonstrating substantial changes in biodiversity and ecosystem composition during the last 6000 years as a consequence of long-term climatic and environmental transformations.

The study also highlights the importance of fossil algae and cyanobacteria as bioindicators of ecological change. Taxa such as Pediastrum, Botryococcus, and Gloeotrichia reflect variations in lake level, trophic conditions, and water quality, providing valuable insights into long-term ecosystem evolution and emphasizing the importance of biodiversity conservation under ongoing climatic and anthropogenic pressures.

This work was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – 558487406.

The Eastern Adriatic provides a promising archive of Holocene plant biodiversity, framed by post-glacial climatic recovery and anthropogenic environment tempering processes which ultimately sculpted the modern Mediterranean biome. This study synthesizes regional palynological and geochemical datasets, focusing predominantly on published studies from the Kornati Archipelago and Mljet to track spatial and temporal shifts in regional Adriatic flora. Early Holocene pollen records from key coastal sites like the island of Cres and Vransko jezero near Biograd document the dominance of mesic forest taxa such as deciduous oak, hazel and pine.

Progressive anthropogenic pressure can be discerned through the appearance of cereal pollen at Čepić polje, olive and grape at Bokanjačko blato, Roman vineyards along the Neretva and persistent charcoal and burn horizons at Prapoče. The evidence traces a Neolithic-to-Roman arc of clearance that gradually replaced evergreen and deciduous oak forests with maquis, garrigue and pasture enhanced by abrupt events including the 8.2 ka cooling, sapropel S1 deposition, and Holocene sea-level fluctuations.

Cave deposits from Spila na Procjepom on Mljet island confirmed Mediterranean evergreen forest dominance alongside clear anthropogenic degradation toward maquis, while a Kornati islands’ marine core resolved the local imprint of the 8.2 ka event, vegetation responses to sea-level rise, and persistent low-intensity human pressure.

Our study seeks to address and resolve several remaining issues, such as differentiating between climate-driven or anthropogenic influences on the Kornati flora, determining the precise timing of Mediterranean sclerophylly appearance, and how the insular biogeography of these islands mediated the 8.2 ka response.

The spatially complex area of the Southern Caucasus is a unique laboratory to study the regional impact of global climatic changes on vegetation. Pollen archives from the Armenian Highlands and western Georgian lowlands reflect the diversity of landscapes as well as the regional differences of Early Pleistocene Glacial-Interglacial variability.
In southern Armenia, pollen data document a clear vegetation response on orbitally forced climatic changes with open vegetation during glacial as well as less pronounced interglacial phases, and the expansion of woody vegetation during and after very warm and humid interglacials. Furthermore, the age of the numerous macro floral assemblages could be constrained to the warm and more humid parts of the climatic phases, confirming the expansion of forests at that time. Still, diversity remains low in this overall dry environment.

In western Georgia, pollen data show no change in lowland vegetation despite some fluctuations in pollen assemblages. Climate remained warm and humid throughout the Early Pleistocene supporting broadleaved mixed beech forests. Accordingly, pollen richness and diversity decrease only slightly with time due to stepwise extirpation of thermophilus taxa during glacial phases while evenness remains high in the relatively stable environment. Here, the uplift of the Caucasus mountain range counteracted global climatic forcing.

This unique interplay of global climate, regional topography and tectonic effects led to favorable climatic conditions for the development of the Colchic vegetation refuge in western Georgia and the high biodiversity in the Caucasus in general.

3D-printed pollen models have been extensively used in research, education and outreach. Wilson (2023) introduced the 3D Pollen Project using confocal laser scanning microscopy (CLSM) to produce accurate series of tightly-focused cross-section images through pollen grains, then produced 3D-printable surface files. Here I present 3D-printed pollen models for over 50 Chinese plant species (MPV 1.0, Make-Pollen-Visible Project), using high-resolution and multiple images of scanning electron microscopy (SEM) to reconstruct STL (Standard Tessellation Language) files for 3D-printing. The sculpture patterns are clearly visible, almost identical to SEM pollen images.
China’s vegetation types are remarkably diverse, encompassing over 30,000 species of seed plants. However, a substantial number of plant species have yet to carry out detailed pollen morphological investigation. Thus both new pollen flora illustrated with pollen images by light microscope (LM) and 3D-printed pollen models are useful in future palynological practice, and especially the 3D-printed pollen models are better for beginners of pollen analysis than 2-dimension pollen images to have a full understanding of pollen morphology. More 3D-printable pollen surface files are awaited to be produced in this project.

The Aptian–Albian transition (c. 113 Ma) represents a major upheaval in global vegetation with the rapid distribution and diversification of angiosperms. In southern England, this interval is represented by the Lower Greensand Group (c. 119-112 Ma), a series of shoreline/nearshore deposits derived from the London-Brabant landmass – the youngest and last truly known terrestrial sediments derived from Mesozoic Britain. Previous work has provided foundational taxonomic context as well as an overview of the broad nature of the vegetation. Following this, we quantitatively examine the taxonomic composition of pollen and spores from outcrop and borehole samples from southern England to expand on our knowledge of mid-Cretaceous sporomorph assemblages in this area. In this poster, we outline our preliminary results with an overview of the taxonomic composition and evaluation of the regional presence of angiosperm pollen during this time. Through harmonising the taxonomic classification of Aptian–Albian pollen and spore in different geographical regions, we aim to integrate our findings into the reconstructions of large-scale patterns of plant biodiversity, such as the latitudinal diversity gradient, to understand how angiosperms became core components of global ecosystems.

We report the first systematic description of Permian plant macrofossils from the Lower Permian Gipshuken Formation on Spitsbergen, Svalbard, Arctic Norway. Several conifer shoots from a fossil plant horizon in the lower Vengeberget member are assigned to the genus Quadrocladus. The plant-bearing interval occurs within stacked anhydrite–dolomite–marl successions of the Vengeberget member that record a shallow marine to supratidal sabkha system on an extensive carbonate platform in a semi arid climate, characterized by hypersalinity, low taxonomic diversity, and evidence for palaeosol formation and vegetation growth on exposed shoals and platform interiors. The Quadrocladus shoots display pronounced xeromorphic traits, notably very short and narrow leaves, consistent with adaptation to water stress in semi arid, periodically desiccated playa–sabkha settings. Comparison with younger occurrences from the Kungurian Tregiovo flora and Late Permian Angaran and Zechstein successions shows that the Spitsbergen record is so far, both the oldest and the northernmost known occurrence of Quadrocladus. These findings imply a boreal, semi arid origin for this xeromorphic, stress tolerant conifer and provide a key high latitude data point for reconstructing Early Permian vegetation dynamics and the subsequent palaeobiogeographic expansion of Quadrocladus across Pangaea.

The occurrence of plant fossils on oceanic islands has been reported in numerous archipelagoes worldwide, although these records remain typically understudied. This is also the case for the Canary Islands, where palaeobotanical research is still limited. In addition, most of this research has been focused on the fossil localities from Gran Canaria Island, being the plant fossil record from the rest of the archipelago less studied. Here, we present the palaeoflora from seven Middle Pleistocene fossil localities, exceptionally preserved within pyroclastic deposits from the Fasnia Member (Diego Hernández Formation) of the Bandas del Sur region, on Tenerife Island. With this aim, gathering of stratigraphical and taphonomical data and collection, preparation and registration of fossil material were carried out. A total of 441 remains were studied. Next, they were described and compared with current plant individuals. The preliminary results indicate the presence of roots of cf. Phoenix; stems of Euphorbia canariensis L; leaves from cf. Visnea, cf. Sideroxylon, cf. Jasminum, cf. Pistacia; and stems and leaves from cf. Kleinia and Aeonium sp. in anatomical connection. The taphonomical analysis suggests the autochthony or parautochthony of the remains. These data allow us to reconstruct the paleoflora that developed on the south of Tenerife Island during the Middle Pleistocene, which will be useful for understanding the biota's response to environmental changes on mid-latitude oceanic islands.

The Borkowice-Radestów ceramic clay mine in Borkowice village is located near Przysucha in the Holy Cross Mountains subbasin in Poland. The exposed sediments belong to the middle-upper part of the late Hettangian Przysucha ore-bearing Formation and represent marginal marine sediments of barrier–lagoon origin. The sample gathered from kaolinitic clays, provided by the late prof. G. Pieńkowski, contains spores and pollen grains and plant macroremains, mainly ginkgophyte Czekanowskia leaves, some with endophytic fungi.

Spores and pollen grains belong to various plant groups, including bryophytes, lycophytes, sphenophytes, ferns, cycadaleans, bennettitaleans, caytonialeans and other seed ferns, erdtmanithecaleans, and conifers. Palynological analysis shows differences between samples of the same age from other localities from the northern Mesozoic margin of the Holy Cross Mts and indicates that the plant cover in the Borkowice area differs from other places, probably due to local conditions.

Preliminary identification of plant macroremains points to a rather poorly diversified flora dominated by Czekanowskia and other ginkgophyte taxa. Badly preserved Neocalamites sandstone casts, associated with dinosaur tracks, were also found.

Dark septate endophytic (DSE) fungi colonising the tissues of Czekanowskia leaves were investigated. A characteristic feature of DSE fungi is the production of microsclerotia. The Jurassic microsclerotia from Borkowice resemble the leaf-like morphotypes of modern DSE microsclerotia and constitute a new and important fossil record of plant–fungal interactions in the Mesozoic.

This research was funded by the National Science Centre (grant no. 2022/45/B/NZ8/02000) and by statutory funds of the W. Szafer Institute of Botany, Polish Academy of Sciences.

The upper member of the Saq Formation (Sajir Member) of Saudi Arabia is characterized, in its upper part, by strongly bioturbated, medium to fine-grained sandstones with intercalations of matrix-supported conglomerates passing upwards to laminated mudstones. At outcrop, these beds are relatively rich in fossils including trace fossils, lingulids and graptolites, which indicate a Dapingian to late Darriwilian age. In the subsurface, the Sajir Member yields a distinctive palynological assemblage characterized by cryptospore dyads, monads of uncertain affinity (“sporomorphs”), and morphologically distinct acritarchs which mostly exhibit short stratigraphic ranges and are thus important as stratigraphic (and possibly paleoecological) markers. The acritarchs are dominated by non-spinose, discoidal forms exhibiting variously perforate/foveate ornamentation and by thin- to thick-walled spherical morphotypes with granulate to reticulate surface ornamentation, or exhibiting thin flanges surrounding thick-walled central bodies. As such, the acritarch assemblage contrasts with the more typical contemporaneous acanthomorphic-dominated assemblages known from many peri-Gondwanan successions. Several taxa correspond to forms previously reported from Saudi Arabia and Oman but left in open nomenclature, whereas others appear to represent undescribed morphotypes and potentially new taxa. The sporomorph component includes cryptospore dyads and other simple terrestrial palynomorphs, possibly indicating an early diversification of land-derived microfloras along the northern Gondwanan margin during the Early to Middle Ordovician. Some similarities are noted with an independently dated Dapingian palynological assemblage described from the Fossil Mountain locality in Utah, USA. The distinct taxonomic composition of the assemblage suggests deposition in a terrestrially-influenced shallow marine environment, consistently with the sedimentological context.

The study investigated climatic and ecological stress of selected gymnosperms from the Upper Triassic (Norian) to the Upper Jurassic (Kimmeridgian), in samples collected from eight sites representing the Norian, Hettangian, Bathonian, and Kimmeridgian stages. Carbon (δ13C) and nitrogen (δ15N) isotope ratios were measured to evaluate environmental stress and nitrogen availability in different habitats, and stomatal indices and cell density were analyzed to study plant responses to changes in environmental conditions.

δ13C values served as indicators of environmental stress, because photosynthetic pathways discriminate differently against 13C under stressful conditions. More negative δ13C values indicate lower stress and greater environmental stability. Within the Norian two localities showed relatively less negative values (around −24‰), suggesting higher stress levels, whereas one Norian locality (−29.29‰) and the Hettangian locality (−30.76‰) reflected the most stable environmental conditions. Bathonian and Kimmeridgian values ranged from approximately −26‰ to −27‰, indicating moderate stability.

δ15N values provided information on nitrogen availability and competition within ecosystems. Norian samples showed relatively uniform values (~5‰), while samples from the Hettangian and one Bathonian locality showed lower values (~2‰), indicating improved nitrogen access. Exceptionally negative δ15N values registered at other Bathonian (−5.79‰) and Kimmeridgian localities (−5.09‰), suggesting unusually high nitrogen availability in these areas. The correlation was observed between the variation of SI and cell density values in different plant species and the differences in 13C and 15N values from the same localities.

This research was funded by the National Science Centre (2022/45/B/NZ8/02000) and the W. Szafer Institute of Botany, PAS.

This study presents a new morphotype of lignified leaves from the South Bohemian basins. New material consisting of leaf fragments from the Coniacian of the Klikov Formation come from a drill core in vicinity of České Velenice. The Klikov Formation is 350 m thick, primarily filled with material of fluvial origin consisting of fossil leaves, charcoalified mesofossils and silicified tree trunks.

Fragmented fossil leaves from the České Velenice borehole were gained by bulk maceration and sieving. The material was selected based on leaf macro- and micro- morphology. The cuticle of tiny, dentate leaves is difficult to macerate because of their fragility caused probably by certain degree of charcoalification. The cuticles observed are described as moderately thick to thick sometimes papillate, showing anomocytic and cyclocytic stomata often surrounded externally by pronounced wrinkling. It is particularly of interest that entire multicellular trichomes have been preserved on cuticles.

A preliminary reconstruction of the Klikov vegetation defines palaeoenvironments: 1) river floodplains dominated by platanoids and lauroids, 2) exposed soils dominated by bryophytes and small monocots, and 3) upland vegetation colonised by the Normapolles complex, mesophytic-xerophytic ferns, and gymnosperms. Within this framework, the studied leaf cuticles exhibit xerophytic features typical of the upland environment. This study offers a rare glimpse into the composition and xerophytic adaptations of Coniacian upland vegetation, enriching our understanding of the Klikov Formation flora.

Acknowledgements: This study was financially supported by the Czech Science Foundation (GAČR) 23-05142K.

Solar ultraviolet-B radiation (UV-B, wavelengths 280–315 nm) has fundamental influence on terrestrial biological processes, due to its characters of high energetic, ability of breaking chemical bonds, and damage to DNA and cell membranes. The ultraviolet absorbing compounds (UACs) in palynomorphs act as key protective components against the deleterious effects of UV-B radiation and have been proposed as a proxy for reconstructions of past UV-B radiation. To investigate plants’ abilities in synthesising UAC and producing pollen grains under UV-B radiation, controlled experiments are useful to isolate the effects of specific drivers. We therefore compared UAC signals in both potted cultivars and branch cuttings in a controlled setting using a UV-B treatment and control. We assessed both pollen malformation rates and the quantity the UAC signals through both thermally assisted pyrolysis gas-chromatography mass-spectrometry (THM-py-GC-MS) and Attenuated Total Reflectance Fourier transformed Infrared Spectroscopy (ATR-FTIR). Overall we find differences in the malformation rates and UACs when comparing potted cultivars and branch cuttings. We also find a moderate negative correlation between malformation rates and UAC signals, suggesting the role of UAC in protecting stability in mitosis stages. Our findings overall contribute to understanding on influence of different forms of materials controlled experimental settings.

Pollen is the most common terrestrial fossil with extensive use in paleoenvironmental and palaeoecological studies. Given that pollen from anemophilous taxa can be transported considerable distances there is a need to assess how well the niche of taxa can be modelled using pollen distribution data. The aim of this study is to test whether pollen records can be used in niche models to predict tree ranges using climate variables and elevation data. Which can then be applied to our understanding of using fossil pollen records to model the potential distribution of taxa in the past. Here we examine whether maximum entropy (MaxEnt) modelling can be used to predict comparable niche estimates using modern pollen distribution data and known species distribution records. Eight conifer genera were selected: Cathaya, Cryptomeria, Cunninghamia, Keteleeria, Pseudotsuga, Sciadopitys, Sequoia and Tsuga. Based on the measure of overlap between the modelled ranges using the different distribution records, the models show high comparability for Pseudotsuga, Sequoia and Tsuga, some comparability for Cathaya and Keteleeria and no comparability for Cryptomeria, Cunninghamia and Sciadopitys. Differences in comparability between the models runs using pollen distribution and genus distribution records are present and likely driven by pollen dispersal mechanisms and deforestation. The results of this study indicate that caution must be taken when interpreting the most likely niche space (MLNS) predicted using fossil pollen distributions due to differences in pollen dispersal and levels of deforestation.

The first Carex L. fossils from Macaronesian archipelagos were found in 1859, within the 1.3 Ma (Late Pleistocene) Porto da Cruz sediments (PdCs) in Madeira Island. These were described by O. Heer (1809-1883) in 1864, as belonging to two taxa: i) ‘1. Carex?’: based on leaf and isolated achene fossils morphologically similar to “C. myosuroides Lowe”(nom. illeg.), an extant plant recently redescribed as a new Madeiran endemic C. sequeirae Míguez & al., and ii) ‘2. Carex?’: based only on leaf fossils. Later, in 1882 leaf and spike fossils were collected in PdCs but not studied. Since then, Madeiran Carex fossils have been neglected. Here we briefly illustrate and discuss, based on historical and new data, the taphonomy, palaeoecology and palaeobiodiversity of Carex from the Early Pleistocene of Madeira Island. Briefly, the fossils occur as impressions/compressions within a fluvial deposit, locally associated with a lenticular silty limestone layer that covers a palaeosol. Taphonomically, the sedges were growing in the margin of a palaeostream and were quickly buried in situ, allowing their preservation as whole plants or as dispersed organs. Comparison of extant Madeiran native (including endemic) Carex spp. and the fossils, especially the spikes, utricules and achenes using optical microscopy and scanning electron microscopy allowed the preliminary identification of two fossil morphotypes: one aff. C. sequeirae and the other aff. C. lowei Bech., although achenes of the latter are half the size. Additional detailed morphological and anatomical comparison will allow the systematic position of the Madeiran sedge fossils to be disentangled.

During the Late Triassic, forests in the Central European Basin developed under a seasonal subtropical climate. Although fossil wood from this interval is abundant, its paleoclimatic and paleoecological significance has so far remained largely unexplored. Here we investigate a silicified log and associated wood fragments from the Löwenstein Formation near Bayreuth in southeastern Germany. These fossils are assigned to Agathoxylon sp. based on araucarian radial tracheid pitting and araucarioid cross-field pitting, representing the first unequivocal record of this genus from the Bayreuth region. Height reconstruction using an allometric tree growth model from a trunk diameter of 0.65 m suggests that the source tree reached approximately 43 m, indicating tall, long-lived conifers and old-growth forest elements in the Norian landscape. More than 20 successive growth rings, including biennial narrow rings, yield a mean sensitivity of 0.67, reflecting interannual variability driven by alternating wet–dry seasons typical of a semi‑arid sub-tropical setting; false rings further record episodic water stress during the growing season. Anatomical evidence of both white-rot and brown-rot decay documents post-mortem saproxylic activity. Together, these data reveal a dynamic ecosystem in which large conifer trees endured fluctuating climate stresses while providing substrate for diverse fungal decomposers, thereby shedding light on nutrient cycling processes in Triassic continental forests. Our results highlight the importance of fossil wood in reconstructing ancient forest resilience, with implications for understanding vegetation dynamics under contemporary climate change.

Here we present coccolith imprint, or “ghost”, fossils preserved on the surfaces of palynomorphs. These unusual fossils have now been found on pollen, dinoflagellate cysts, prasinophyte algae, and acritarchs (in this case, probably green algae). Following a review of, to our knowledge, all known reports of coccolith imprints, we show that these fossils occur globally and have been found in every geologic period since the appearance of coccoliths in the Triassic. The fossils themselves are difficult to distinguish under light microscopy and generally appear as small round- or oval-shaped features on palynomorph surfaces. Indeed, caution should be applied when identifying these fossils since they can closely resemble, and therefore easily be mistaken for, a range of features, including apertures, surface ornamentation and pyrite framboid voids. However, fluorescence microscopy can assist in their identification, and scanning electron microscopy can unequivocally reveal their presence. This study highlights the utility of the traditional palynological method to calcareous nannofossil research. With this approach, we emphasize the need for increased awareness of coccolith imprints preserved on palynomorphs, but also demonstrate how their occurrence can help with biostratigraphy and reconstructions of past environments.

Wildfires were widespread in terrestrial Cretaceous ecosystems on a global scale. As the product of incomplete combustion, charcoal is chemically inert and highly insusceptible to microbial decay, making it an exceptional medium for reconstructing the taxonomic composition of floras affected by wildfires. During the Early Cretaceous, a ‘high-fire’ period of Earth’s history, a complex evolutionary feedback loop has been hypothesized to have existed between high fire frequencies and the rapid radiation of early angiosperms. Despite the evolutionary significance of this floral transition, detailed taxonomic and ecological studies of charcoal-bearing localities remain scarce due to severe mechanical compaction in the vast majority of clastic sediments. This study investigates excellently preserved Cretaceous charred plant remains found within fissure fills in Devonian reefal limestones in the Sauerland region (W-Germany). Serving as classical taphonomic Konservat-Lagerstätten, these fissures protected brittle charcoal from mechanical stress, yielding uncompacted, three-dimensionally preserved specimens. Morphological and anatomical investigations utilize standard micropaleontological screen washing and sieving, followed by high-resolution Scanning Electron Microscopy (SEM). Preliminary results reveal a diverse morphological range of charcoalified remains, prominently characterized by conifer wood and leaf tips showing distinct cellular diagnostic features, alongside various (fragmentary) pinnule remains of ferns. This exquisite preservation provides a crucial taphonomic window to evaluate new aspects of the structural diversity and palaeoecological dynamics of terrestrial vegetation during a critical phase of the mid-Mesozoic terrestrial revolution.

Cycads are the extant gymnosperm clade with the greatest ecological diversity, with species adapted to deserts, mangroves, and wet tropical forests. They display a wide range of growth forms, including subterranean stems, aerial trunks, and even epiphytic habits, as in Zamia pseudoparasitica. Cycads are also exceptional among gymnosperms for their high level of insect pollination. Recent studies suggest that cycad species richness is relatively recent, with most extant clades diversifying during the Mid-Miocene. Interestingly, the ghost lineage represented by the leaves of the Ctenis clade disappeared during the same period. These fossil plants differed markedly from extant cycads by the presence of anastomosing venation. However, the relationship between fossil stems and extant cycads is still unclear. The present study focuses on cycad stem anatomy and related fossil taxa such as Medullosales or Callistophyton.

We analysed the anatomy of fossil stems present in the collections of the Senckenberg Research Institute and Natural History Museum, and performed multiple measurements of the arrangment of the leaf bases, microanatomy, and we constructed 3D models of the specimens for geometric morphometrics. We then revised the literature on fossil cycad stems, finding that several species exhibit unusual anatomical features, including sterome-like tissues, extrafascicular bundles, and vascular cylinders with inverse secondary xylem differentiation. We discuss the impact of the Mid-Miocene transition on extant cycad diversity, particularly within Zamiaceae, in relation to stem anatomy and microanatomy characteristics.

Ginkgoales were an important component of Mesozoic floras, yet their modern diversity is restricted to the single living species Ginkgo biloba L. The long evolutionary history and conservative leaf architecture of this group make fossil ginkgoaleans valuable for exploring plant diversity, morphological persistence and environmental adaptation through geological time. Here, we present a systematic and morphometric study of Early–Middle Jurassic ginkgoalean fossils from the Dameigou area and nearby localities in the Qaidam Basin, northwestern China.

A total of 128 specimens from eight fossil-bearing horizons were examined, with emphasis on three common genera: Ginkgoites, Baiera and Sphenobaiera. By integrating macro-morphological observations, cuticular characters and multivariate analyses of measurable leaf traits, ten species are recognised from the studied succession. The results demonstrate that ginkgoaleans were taxonomically and morphologically diverse in the Qaidam Basin during the Early–Middle Jurassic. Quantitative analyses further show that leaf macrocharacters can support genus-level classification, especially for specimens without preserved cuticles, although species-level identification remains difficult because of overlapping leaf forms and possible heterophylly. In contrast, epidermal and cuticular features provide additional evidence for refining taxonomic assignments.

Several species, including Ginkgoites qaidamensis (Li) Zhang & Wang, G. longifolius Harris and Sphenobaiera spectabilis (Nathorst) Florin, occur across multiple stratigraphic levels and show limited morphological change through time. This pattern suggests a degree of morphological stability among Jurassic ginkgoaleans, even under changing local environmental conditions. Overall, the Qaidam material provides an important record for understanding the diversity, classification and evolutionary resilience of Ginkgoales during the Early–Middle Jurassic.

The bryophyte fossil record is notoriously scarce due to different biases, most of which are associated with their size and the lack of researchers specialized in this group. Among the ~650 fossil bryophyte taxa recognized to date, hornworts (Anthocerotophyta) are represented by only four taxa, of which two are only tentatively assigned to the group. Here we report new fossil hornwort specimens from Miocene strata (~7 Ma) in eastern Romania. The fossils are found in a 1-meter-thick layer of grey clayey marls that represents a shallow lacustrine to paludal depositional environment.

The gametophyte thalli, up to 6-7 mm across and ~1 mm thick, are rosette shaped with lobed outline and their anatomy is well preserved. Multiple large empty chambers (0.5-1.0 mm) present close to the lobe tips probably correspond to mucilage cavities. There is no dorsiventral differentiation in the histology of thalli, but there is a system of radiating narrow canals that dichotomizes following the general morphology of the thallus. The sporophytes, >5mm long, have bases deeply embedded in the gametophyte thalli. They have a central tissue resembling a columella forming a bundle of 16 cells and a surrounding layer of variable thickness (mostly 1-2 cells thick). The variable thickness of this layer indicates that the sporophytes are probably missing some of the outermost cell layers. These new hornwort fossils represent a 25% increase in the number of known fossil hornworts (now with five fossil types) and represent the only fossil record of Cenozoic age for the group.

A small filicalean stem, Tubicaulis weiningensis sp. nov., was discovered in the Late Permian Emeishan Basalt Formation of western Guizhou, China. It represents the first record of this genus in the Cathaysian Flora. The new fossil consists of a large central stem surrounded by a few petiole bases and adventitious roots. The stele is an ectophloic dictyoxylic siphonostele with a few leaf gaps. The leaf traces in the cortex change from an initially thick rod-shaped to abaxially curved C-shaped, with the tips incurved. When the leaf trace separates from the stele, it bears endarch protoxylem strands. Irregularly shaped sclerenchyma bundles are distributed in the concave region of the leaf trace vascular bundle. Root traces emerge laterally from the tips of the leaf traces. The adventitious roots extending along the long axis of the stem indicate an erect growth habit of a small fern. Previously reported Tubicaulis species possess a primitive protostele, and from the Early Carboniferous to the Late Permian the stele gradually became parenchymatized. The present fossil exhibits an ectophloic dictyoxylic siphonostele, representing the advanced stele type in the genus. The fossil record shows that from the Pennsylvanian to the Lopingian, the stele of Tubicaulis evolved from a protostele without leaf gaps to a siphonostele with distinct leaf gaps, accompanied by an increase in parenchyma. The future discovery of more types of filicalean stem fossils in western Guizhou will provide further evidence for understanding the evolution of ferns and community paleoecology.
Keywords: fern, Permian, Anachoropteridaceae, stele, evolution, erect growth

Palynology and palynofacies are central to stratigraphic and palaeoenvironmental interpretation of the Middle Jurassic Brent Group, one of the main reservoir intervals of the North Sea. However, several parts of the succession are dominated by anomalous palynological assemblages, including leiosphaerid-like forms, indeterminate spheromorphs, degraded bisaccate-like structures, and palynomorph-sized plant fragments of possible bryophytic affinity. These intervals have commonly been treated as poor-recovery horizons or taphonomic noise, although they may preserve evidence of salinity stress, organic-matter sourcing, and coastal ecosystem instability.

Here we present new data from Well 30/11-14, Norwegian Sector, based on 52 core samples spanning a c. 210 m interval through the Heather, Tarbert, and Ness formations. More than 12,000 palynomorphs and 13,350 organic particles were counted, yielding 103 palynological taxa, including 74 terrestrial and 29 marine taxa. Quantitative palynological and palynofacies data reveal strong stratigraphic variation in marine, brackish, and terrestrial components. Spheromorph-rich assemblages, locally exceeding 80%, occur in tidal-flat, tidal-channel, and offshore facies, whereas amorphous palynomorphs reach more than 90% in selected levels. These patterns suggest repeated shifts in restriction, salinity, oxygenation, and terrestrial input.

Ongoing SEM and TEM analyses indicate that these problematic forms are not taxonomically or environmentally uniform. Some bisaccate-like structures are unlikely to represent true pollen, dominant spheromorphs may include algal forms linked to salinity-stressed conditions, and several Dissiliodinium willei-like specimens show low-relief sutural features only visible under SEM. This study reframes problematic assemblages as palaeoenvironmental evidence rather than analytical noise.

In recent years, variations in acritarch morphotypes and morphological parameters, particularly process (appendage) length, have been studied to understand the palaeoecology of acritarchs and environmental changes, for example, salinity, temperature, and oxygenation. The acritarchs from the Early-Middle Ordovician of the island of Öland, Sweden, have been studied with a focus on taxonomy and biostratigraphy. Recently, Calero-Gordon et al. (2025) investigated the palaeoecological distribution of acritarch assemblages from two Middle Ordovician sections on the island. Following these studies, several open questions remain. In this study, based on the same sections, changes in the morphology of selected acritarch morphotypes are analyzed across a regressive event recorded in the Öland shelf sequence. Our dataset includes investigations on additional morphotypes, in particular the fusiform acritarchs, the sphaeromorphs and the baltisphaerids, that are here subdivided into two groups with the presence or absence of basal plugs. Measurements of the process length and the central body diameter across these groups, combined with statistical analysis, reveal distinct patterns, most probably related to water depth: baltisphaerids without basal plugs and fusiforms dominate in shallower water settings (Hälludden section), while baltisphaerids with basal plugs are more abundant in deeper water settings (Hagudden section). Process length increases with water depth, whereas small-sized forms become rare in deeper water environments. The presence of basal plugs possibly represents an adaptation for flotation and water-column stability. Sphaeromorph acritarchs appear palaeoecologically widespread and are morphologically stable. Overall, this study confirms that detailed acritarch morphometrics can refine palaeoenvironmental reconstructions beyond their traditional biostratigraphic role.

Dinoflagellates play a key role in marine ecosystems and are known for producing organic-walled cysts (dinocysts), which are valuable for reconstructing paleoceanic and climatic variability. Analyses using Attenuated Total Reflection Micro–Fourier Transform Infrared Spectroscopy (ATR–micro FTIR) have identified the molecular structure of dinosporin, the primary constituent of the dinocyst wall. Dinosporin is a stable, carbohydrate-based biomacromolecule that may exhibit variable contributions from certain functional groups (Meyvisch et al., 2023).

Recently, we assessed the compositional stability of dinosporin during early diagenetic processes associated with the fossilization of modern dinocysts fossilization of modern dinocysts, across shallow to deep-marine settings spanning the Upper Pleistocene to Holocene. Our findings demonstrate that dinosporin remains largely unaltered, reiterating its remarkable biomolecular stability. However, the integrity of dinosporin under extreme climatic perturbations remains poorly constrained.

Therefore, we are investigating the response of dinocyst wall chemistry to global warming by combining experimental and paleontological approaches. Cultures of living dinoflagellates are subjected to controlled environmental stressors analogous to major geological events, namely the Paleocene–Eocene Thermal Maximum (~56 Ma) and the Late Maastrichtian Warming Event (~66 Ma). In parallel, fossilized dinocysts from these intervals will be analysed.

A combination of spectrochemical techniques, including ATR–micro FTIR, and mass spectrometric methods will be employed to characterize molecular modifications, trace-element incorporation, and adaptive responses in cyst wall chemistry. Integrating experimental and fossil evidence will improve our understanding of dinocyst resilience to rapid climate change and contribute to the development of novel biomarkers for reconstructing past and future environmental variability.

Ecosystem- and Climate change are politically important and exciting topics of particular public interest. Palaeoclimate analyses play a crucial role when differentiating between anthropogenically and ‘natural’ climate change. In popular media, results of such analyses are often reflected in a simplified, confusing, or even altered way. Particularly the methods behind presented (palaeo-)climate data are often not revealed to non-scientists.

A good way to introduce ‘natural’ ecosystem and climate change to non-scientists and to increase their understanding of scientific research are simplified case studies. Here, we show such studies with focus on pollen analysis. We discuss the applicability of such studies to museums, schools, and university teaching, with focus on three-day pollen course developed for primary school children. In this course, theoretical background to vegetation and climate development is combined with haptic and artistic activities, resulting in simple self-made ecosystem models for the Pleistocene-Holocene transition. We furthermore show how modifications of such courses can be implemented in shorter public events or in teaching.

Estimating plant diversity through geological time is confounded by several biases. These can arise from the structure of databases as well as from the nature of plant fossils. Occurrence-based databases such as the Paleobiology Database (PBDB) record successful fossil sampling, and therefore cannot distinguish between true absence and false fossil absence caused by missing rock record. In addition, the database’s implicit proxy for rock availability, stratigraphic formations, is partly informed by subdivision of strata using faunal and floral turnover (i.e. biozones), causing bias towards higher formation number in fossiliferous vs non-fossiliferous strata. Plant fossils present an additional challenge because they are commonly represented by isolated organs that are non-uniformly preserved through time and space, and vary in informativeness and taxonomical resolution.

To investigate the extent of bias affecting our understanding of the plant fossil record, we used the Macrostrat database, which quantifies rock availability using lithological area and unit thickness (i.e. rock volume) independently of fossil occurrence data, thereby reducing occurrence and formation biases. We expanded Macrostrat’s South American coverage and constructed structural equation models integrating multiple rock-availability metrics derived from both databases with two curated, organ-specific diversity estimates through the Phanerozoic from the PBDB, namely leaves (1) and pollen & spores (2).

Our analyses reveal that sampling proxies exert heterogeneous effects on different organ records, with the rock volume showing a substantially stronger influence on leaf diversity than on pollen & spore diversity. We discuss the resulting implications for estimates of plant diversity through time and space.

The Barremian fossil site of Las Hoyas (Cuenca, Spain) constitutes one of the most relevant Konservat-Lagerstätten for the study of Early Cretaceous continental ecosystems, standing out for the exceptional preservation of its biota. In this context, the palaeobotanical record provides a unique opportunity to address the palaeoecological reconstruction of the wetland system, particularly through the analysis of poorly studied plant macrofossils.

This work analyses two complementary assemblages of plant fossils: a collection of 168 seeds and a set of 34 leaf impressions previously attributed to angiosperms, housed at the Museo Paleontológico de Castilla-La Mancha (MUPA). The main objective is to determine their morphological diversity and preliminary taxonomic affinities in order to infer their palaeoecological implications within the wetland.

The seeds were examined using morphological criteria, including length/width ratio, ornamentation, and the presence of associated structures, allowing the identification of six main morphotypes, including winged, striated, and pedunculated forms. Their morphological features indicate the presence of both angiosperms and gymnosperms, highlighting the identification of seeds attributable to the Caytoniales, suggesting a greater diversity than previously recognized for the wetland.

Leaf analysis allowed the definition of eight morphotypes, seven attributed to angiosperms and one to Caytoniales of the genus Sagenopteris. Overall, the results indicate a more heterogeneous flora than previously documented, including both autochthonous and allochthonous components. Although angiosperms and Caytoniales are scarce within the assemblage, their morphological and adaptive features, together with their temporal distribution within the Las Hoyas wetland system, suggest the occupation of distinct ecological niches.

The extraordinary biodiversity of the Amazon is the product of complex, deep-time interactions between Andean tectonics, climate and biota. The Miocene is a particularly important interval in this history, characterized by ongoing landscape reorganization that gave rise to a western Amazonian mega-wetland (the Pebas system). This system transitioned into the fluvio-lacustrine Acre system and ultimately the modern eastward-flowing Amazon River. Although Andean uplift, drainage reorganization and climate change are recognized as drivers of diversification, interactions between these processes and vegetation dynamics remain poorly constrained.

In this study we present palynological data from the 923m Acre drill core, the first recovered by the Trans-Amazon Drilling Project, and explore how western Amazonian biomes shifted alongside the development of the modern trans-continental river system. Comparison of pollen assemblages in the Acre core to existing regional biostratigraphic zonations suggests the sediments span a younger interval previously unrecorded, of Late Miocene – Pliocene age.

We address three exploratory research questions: (1) What was past vegetation composition and how did biomes shift? (2) Are biome shifts consistent with independent evidence for Late Miocene Andean uplift, climate change and landscape reorganization? (3) How does this record from a site proximal to the Andes compare with basin-wide signals recorded in a distal setting such as the Amazon submarine fan?

The results are intended as a first step towards integrating the Acre core with other regional datasets, highlighting key uncertainties in interpretation and outlining hypotheses for future quantitative testing.

Poręba is an Upper Silesian Late Triassic locality containing numerous well-preserved macro- and microremains of plants, invertebrates, and vertebrates. The sediments belong to the upper part of the Patoka Member of the Grabowa Formation and were deposited in a braided river system under a monsoonal climate regime. The fragmented preservation of the remains indicates relatively long transport.

The sporomorph assemblage is characteristic of the local Classopollis meyeriana Zone, subzone b, indicating a middle–late Norian age. Both spore-producing plants (lycopsids, sphenopsids, and ferns) and gymnosperms are present, although conifers predominate. Megaspores confirm the occurrence of heterosporous lycopsids, including spikemosses. In contrast, all macroremains belong to conifers. Three types of female seed scale–bract complexes and three types of male cones indicate the presence of at least three conifer species: two representing evolutionarily older members of the order Voltziales and one belonging to the family Cheirolepidiaceae. Most sterile twigs and detached leaves show similar Brachyphyllum–Pagiophyllum-type morphology. However, no branches have been found organically connected to cones, preventing reconstruction of complete plants. Numerous fragments of charred wood assigned to Agathoxylon keuperianum indicate frequent wildfires.

Arthropods are represented by isolated cuticle fragments, possibly belonging to scorpions, and by a single incomplete beetle elytron. Annelids are represented by relatively numerous clitellate cocoons.

This research was funded by the National Science Centre, grant no. 2021/43/B/ST10/00941.

Lueckisporites virkkiae Potonié et Klaus 1954 emend. Clarke 1965 is a distinctive Permian taeniate bisaccate pollen. It is characterised by a smooth corpus, two well-developed sacci, and two prominent proximal taeniae associated with a monolete-like sulcus. Its botanical affinity, historically linked to several conifers, is consistent with Majonicaceae. Since its original definition, the genus Lueckisporites has undergone multiple emendations. While early studies proposed several species and morphotypes, later works emphasised a broad morphological continuum within L. virkkiae, leading to the definition of variants and palynodemes. Recent ultrastructural analyses support the interpretation that this variability reflects intraspecific plasticity, probably driven by hydration–dehydration processes (harmomegathy).

From a chronostratigraphical perspective, L. virkkiae has long been regarded as a key taxon for the late Permian, particularly within Euramerican palynoassemblages. However, earlier occurrences in the lower Permian and its debated global synchronicity have led to increasing uncertainty regarding its chronostratigraphical range. A comprehensive revision of the stratigraphic and palaeogeographic distribution of L. virkkiae is based on published occurrences across multiple basins and phytogeographic provinces. By critically reassessing taxonomic criteria and integrating updated age constraints, we aim to refine its chronostratigraphical range and evaluate its significance as a potential interregional correlation tool in late Palaeozoic successions.

The fossil record from the high-latitude realm in the Late Devonian is less well known than contemporary Euramerican deposits. With a global distribution in the Devonian, Lycopsida form an important component of any flora, for which the South African Witpoort Formation is no exception. Unusual, remarkable specimens have the potential to offer not only palaeobiogeographic information, but important taxonomic features.

Two unnamed lycopod taxa are introduced from the Upper Devonian in South Africa, both bearing sporangia adaxially on the leaves. The first is an archeaosigillariid; comprising an extremely rare fertile example from this group. It has short trifurcate leaves emerging from swollen, probably parenchymatous leaf bases. The sporangia are located on unmodified sporophylls positioned distally on the axes, and appear to have been thin-walled. This evidence supports inclusion of Archeaosigillariaceae in Protolepidodendrales. The second lycopsid has needle-shaped leaves, and bears its sporangia distally on sporophylls modified with sporangial cups. It is compared to the known rhizomorphic lycopsid diversity from the Late Devonian. These two new lycopods contribute to a unique high-latitude Late Devonian flora from Gondwana and can offer insights towards questions of floral exchange and cosmopolitanism during the epoch.

Keywords: Angiosperms, Paleoecology, Palynostratigraphy, Phytogeography, Western Tethys

The Late Cretaceous witnessed a major ecological radiation of angiosperms, marking a fundamental transition from gymnosperm-dominated to angiosperm-dominated terrestrial ecosystems. Despite its significance, the European paleobotanical record for the Coniacian–Santonian interval remains scarce, largely constrained by the paucity of coeval terrestrial deposits. In this context, the Iberian Basin provides a valuable setting to investigate middle Late Cretaceous floras through continental and proximal marine successions.Here, we present a palynological analysis of the Caballar and Montejo formations from the western sectors of the basin (Guadalix de la Sierra and Soto del Real areas, northern Madrid). Both palynofloras are heavily dominated by Normapolles angiosperm pollen. Identified taxa include Atlantopollis verrucosus, Complexiopollis spp., Hungaropollis krutzschii, Longanulipollis coronatus, Trudopollis fossulotrudens, Minorpollis minimus, Triangulipollis sp, Tenerina sp., Classopollis sp., and Araucariacites sp. The composition of these assemblages suggests that Normapolles-producing angiosperms already constituted a major component of the plant communities thriving in the warm tropical lowlands of the Iberian region during the Coniacian–Santonian. Furthermore, the palynological data from the lower Montejo Formation firmly constrains a late Santonian age for the Soto del Real succession, successfully refining previous interpretations based solely on lithostratigraphical correlation.

Funding/Acknowledgements: This research was funded by the Ministerio de Ciencia, Innovación y Universidades (Gobierno de España) through the research project PID2023-148083NB-I00, and by the Competitive Reference Group of the Xunta de Galicia (GRC-ED431C 2025/52).

Cathaya, the sister taxon to Pinus, is one of the most endangered plants endemic to China. The single extant species, C. argyrophylla, survives only on open slopes and ridges in the subtropical mountainous regions of southwestern China. Although Cathaya macrofossils have been reported from several sites across the Northern Hemisphere, they have not been recorded previously from China. Here, we document several well-preserved ovuliferous Cathaya cones from the Upper Miocene Shengxian Formation of Zhejiang Province, eastern China. The ovoid to ellipsoid seed cones possess helically arranged, suborbicular or ovate ovuliferous scales, and concealed subtending triangular-caudate bracts with a tapering apex. Detailed comparisons with extant and fossil species of Cathaya favour assignment of the new fossils to Cathaya sp. cf. C. argyrophylla Chun et Kuang. This discovery shows that Cathaya had a much wider distribution during the Late Miocene than at present, including its establishment in eastern Asia by that time. Moreover, the occurrence of this taxon indicates a warm and humid subtropical climate in eastern Zhejiang during the Late Miocene, which is consistent with previous interpretations based on other plant fossils. The striking decrease in diversity and geographic contraction of Cathaya through the late Cenozoic probably resulted from: (1) regional climatic deterioration; (2) low seed production, germination rates and seeding survival rates; and (3) elevated competition from angiosperms and other gymnosperms.

The Paleocene Eocene Thermal Maximum (PETM, ca. 56 Ma) was a short (200 ky) and major global warming event characterized by a temperature increase of 5 to 8°C and a profound impact on diversity, biogeographic distribution and extinction patterns. The two fossiliferous sites of Rivecourt (56 Ma) and Le Quesnoy (ca. 55 Ma) located in the Paris Basin (Oise, France) provide a valuable opportunity to compare terrestrial paleoenvironments before and after the PETM in western Europe.

Both sites have yielded abundant fossil assemblages including vertebrates as well as a large amount of plant fossils such as wood, flowers, inflorescences, fruits, seeds and amber (only in Le Quesnoy). Previous studies documented a predominantly tropical to subtropical forested environment, comparable to modern South-East Asian ecosystems. However, several questions remain unresolved, particularly concerning the diagenetic history of fossil woods, the origin of their contrasting coloration and preservation and the taxonomic affinities of an inflorescence.

This study aims to address these issues through a multiproxy geochemical approach. Raman and infrared spectroscopy, combined with Rock-Eval pyrolysis and elemental analysis, are used to characterize the immature diagenesis of the samples and investigate potential evidence for local paleo-wildfires. Stable carbon isotopic analysis (δ13C) provides insight into palaeoecological and hydrological conditions. Finally, biomarker analysis (GDGTs, lipids etc…) are used to reconstruct paleoenvironmental conditions and explore the chemotaxonomic affinities of the fossil inflorescence.

The Lusitanian Basin, Portugal has long been an area of focus for studying the diversification of angiosperms in the Early Cretaceous. Coastal outcrop sections from Ericeira have been stratigraphically well-constrained using updated strontium isotope stratigraphy and are thus useful for examining the very early incursions of angiosperms into a gymnosperm dominated habitat. This study examines palynofloral assemblages sampled from nearshore limestones and clastic sediments with the aim of reconstructing the floras, climate and environment in which the early angiosperms began to proliferate.

Palynofloral evidence is indicative of a warm, potentially dry climate dominated by xerophytic gymnosperms. High abundances of Classopollis pollen derived from cheirolepidiacian conifers are observed throughout the section. High abundances of Exesipollenites are observed in the lower half of the section (uppermost Valangian to mid-Hauterivian) but decrease to near absence in the upper half (upper Hauterivian to upper Barremian) as bisaccate pollen derived from pinaceans (Pinuspollenites) becomes more abundant. Isolated finds of monosulcate angiosperm pollen grains (Clavatipollenites, Asteropollis) are observed in the upper part of the section (Barremian). Spores derived from ferns (Cyathidites, Deltoidospora, Cicatricosisporites) and lycopsids (Patellasporites) are indicative of coastal marshes and locally wet conditions, and are found in higher abundances in the more proximal, sand-dominated facies at the base and top of the section. Changes in the spore abundances appear driven mainly by sea-level and transport, whereas shifts in the pollen assemblage appear partially climate-driven.

Palynological analysis of the Falcão-1 well provides new insights into depositional environments and sediment sourcing offshore São Tomé from the Late Cretaceous to Oligocene. Quantitative palynodata are consistently well recovered from cuttings, despite moderate to poor preservation linked to transport-related abrasion.

The Palaeogene succession (Late Palaeocene–Late Oligocene) is characterised by predominantly open marine conditions, reflected by diverse dinocyst assemblages. However, recurrent high abundances of leiospheres indicate input from more proximal settings characterised by stressed surface water conditions. Terrestrial input is limited and dominated by low-diversity miospores derived from coastal swamp vegetation. A notable increase in fungal spores and epiphyllous fungi in the Oligocene suggests enhanced soil development and sustained input from adjacent coastal plains, coincident with phases of increased arenaceous deposition. Stratigraphic discontinuities, including probable hiatuses at the Bartonian-Rupelian and possibly Ypresian-Lutetian boundaries, are interpreted to reflect intensified bottom-water circulation inhibiting sediment accumulation.

In contrast, the Late Cretaceous succession records stronger terrigenous influence under offshore marine conditions. A pronounced influx of freshwater-derived palynomorphs, including abundant Pediastrum and rare Azolla, marks an abrupt increase in fluvial input during the Late Campanian. This interval coincides with the development of a regionally significant deepwater sand system, interpreted as gravity flow deposits equivalent to the Batanga Sands.

Overall, the palynological record captures a transition from terrigenous-influenced Late Cretaceous systems to more stable open marine conditions in the Palaeogene, modulated by episodic increases in continental input and basin dynamics.

During the early Toarcian (~183 Ma), volcanogenic outgassing from the Karoo–Ferrar Large Igneous Province perturbed the global carbon cycle, culminating in the Toarcian Oceanic Anoxic Event (T-OAE). In the Neo-Tethyan realm, this interval is globally tracked by a prominent negative δ¹³C excursion at the base of the Dactylioceras (E.) elegantulum Zone. While the marine expressions of the T-OAE, including widespread dysoxia–anoxia, biocalcification crises, and selective extinctions, are well established, the synchronous response of continental vegetation remains comparatively under-constrained.

Recent palynofloral analyses from Neo‑Tethyan basins have documented a recurrent “fern spike” and shifts in spore–pollen assemblages indicative of canopy collapse, humidity increase, and enhanced wildfire regimes, exhibiting a distinct latitudinal structuring driven by differential climatic forcing across basin margins. To refine the spatial heterogeneity of this floral turnover across the Neo-Tethys, we integrate a new high-resolution palynological dataset from the Iberian Range (Sierra Palomera) with ammonoid biostratigraphy. This approach provides a robust chronostratigraphic framework that clarifies the dynamics, magnitude, and timing of terrestrial biotic responses in the southern sector of the Neo‑Tethyan system during the T-OAE.
Funding/Acknowledgements: This research was funded by the Competitive Reference Group of the Xunta de Galicia (GRC-ED431C 2025/52).

Wildfire risk is increasing worldwide, and the way global peatlands interact with fire has changed throughout the Anthropocene. The UK’s “peatscapes” (interconnected landscapes dominated by peat-forming ecosystems) are extensive, carbon-rich stores that support unique biodiversity, yet they are highly sensitive to environmental change. Anthropogenic impacts, such as land-use change and burning, have driven widespread degradation, making peatlands increasingly vulnerable to fire. Increased fire frequency, together with the impacts of climate change, threatens to alter peat structure and hydrological function and may even transform peatlands into carbon sources, with consequences persisting for centuries. As the UK’s peatscapes become increasingly marginal under climate change, a new understanding of how they have responded to past fire events and long-term environmental pressures is valuable for understanding their future resilience.

This research is addressing questions about peatland resilience to fire by generating new multiproxy knowledge of peatland recovery using palaeoecological techniques applied to peat cores in three UK landscapes: Dartmoor, the Peak District, and the Flow Country. This will be combined with earth observation data collected at annual scales to observe changing peatland relationships with fire prior to and during the Anthropocene under different preconditions. Outputs will enable comparisons between regions with differing vegetation, fire histories, and land-use legacies to determine why peatlands vary in recovery dynamics and vulnerability to changing climate and fire activity. The application of Fourier-Transform Infrared (FT-IR) spectroscopy to macro-charcoal will be used, for the first time in UK peatlands, to characterise natural and anthropogenic fire events.

The Lusitanian Basin (western Portugal) comprises an extensive Cretaceous sequence with well-preserved plant fossils that provides a unique insight into the initial radiation of angiosperms during the Early Cretaceous. Several studies on leaf floras and plant mesofossils from the Portuguese sequence have been more systematically oriented, while palynological studies have to a large extend been devoted to stratigraphic aspects. The Early Cretaceous palynofloras from the Lusitanian Basin have yielded significant data that complement inferences from leaf and mesofossil floras providing important clues for the reconstruction of ancient ecosystems. In the present work, we report on preliminary results of palynological analyses from the Lower Cretaceous (Aptian/Albian) of Catefica, central-western Portugal. The Catefica strata consist of fluvial cross-bedded light-coloured sandstones with intercalated dark clay beds belonging to the Almargem Formation, considered to be of late Aptian – early Albian age. The palynoflora is rich and diverse, dominated by fern spores assigned to the families Anemiaceae, Cyatheaceae/Dicksoniaceae, Lygodiaceae and Osmundaceae, reflecting the existence of swamp pteridophyte vegetation. The occurrence of bryophytes and lycophytes representatives supports the existence of local humid conditions, in the alluvial plain. The presence of xerophytic components, represented by cheirolepidiaceous conifer pollen Classopollis together with bisaccate pollen grains, reflects the existence of conifer vegetation on upland and slopes. Angiosperms are also present, but subordinate. The most common angiosperm pollen is represented by reticulate grains of the Clavatipollenites-type. Furthermore, pantoporate pollen and different types of tricolpate pollen grains were recognised in the palynoflora.

The Paleogene and Neogene of northwestern Bohemia is spread as a continuous zone of magmatic and sedimentary complexes, parallel to the Czech-German boundary. The present overview covers three areas: Doupovské hory Mts., Most Basin and České středohoří Mts. They are all rich in the fossil record, being of interest to the scientific community for many years, but the study of macrofossils primarily focused on leaves, fruits and seeds, and the fossil wood studies were rather limited. Over the past 25 years, the fossil wood research has made significant progress (Koutecký 2024; Sakala 2024). The research was supported by Cooperatio Programme Research Area GEOL and SVV (both Charles University).

Koutecký, V. 2024. Systematic evaluation of the fossil wood record from the Ohře rift area with a focus on the volcanic bodies of the České středohoří and Doupovské hory Mts. PhD Thesis, Charles University, Prague. 35 p. http://hdl.handle.net/20.500.11956/188742

Sakala, J. 2024. Fossil wood analyses: Several examples from five case studies in the area of central and NW Bohemia, Czech Republic. In: Agusti, J. (Ed.): Xylem: Methods and Protocols (2nd edition). Methods in Molecular Biology 2722, Humana, New York, pp. 89–104.

Lepidodendron is among the best known and most iconic fossil plant taxa, with its life restorations being a staple of palaeobotanical art since the 1800s. Despite its ubiquitousness in Carboniferous environmental and landscape reconstructions, the significant advances in our anatomical understanding of this taxon are rarely represented in paleoart, with memetic copies of a few influential reconstructions, often with the same inaccurate anatomies, predominating. In response to its misrepresentation, I present a novel life restoration of Lepidodendron, based on a review of measurements and anatomical details available in the current literature. Based on this new restoration, I compare the up-to-date knowledge of Lepidodendron anatomy with that of pre-existing restorations, allowing an assessment of how this taxon has been misrepresented in paleoart for the past two centuries. The novel restoration shows notable differences in total plant proportions when compared to other restorations, and highlights that simple colour inferences can be made based on the macrostructure and periderm anatomy of the trunk. By highlighting the incongruence between paleoartistic representations and data-driven palaeobotanical reconstructions, this new restoration exemplifies the need for new evidence-informed restorations of fossil plants across palaeobotany as a whole.

In the 1840s, H. Goeppert described the first Triassic flora from the Kluczbork area (Biadacz, Dobieracice, Gosław, Maciejów) in present-day Poland, although he initially interpreted its age as Jurassic. Additional specimens were later collected by F. Roemer, who assigned the flora to the Late Triassic (Rhaetian). The flora consists mainly of horsetails, seed ferns, and bennettitaleans, with ferns, cycads, and conifers also represented. The specimens described by Goeppert are still housed in the Henryk Teisseyre Geological Museum of the University of Wrocław, enabling their revision.
Preliminary analysis revealed that not all illustrated specimens have survived, whereas some taxa are represented by more material than indicated in the original publications. Only one species, Lepidopteris ottonis, had previously been revised by M. Barbacka. This species is an important Rhaetian index taxon originally described by Goeppert from Silesia. Another important species is Neocalamites lehmannianus, one of the most common horsetails of the Late Triassic and Early Jurassic of Europe. The type material of this species has not previously been revised. Additional specimens beyond the two illustrated by Goeppert were identified and show considerable variation in shoot thickness. Goeppert’s material corresponds well with the modern concept of the species despite its confusing nomenclatural history. Bennettitaleans, represented by several species of Pterophyllum, lack preserved cuticles, making their revision difficult. Locating the original fossil localities could allow palynological verification of the flora’s age, which is important given the controversy surrounding Rhaetian sediments in Silesia.

This research was funded by the National Science Centre, grant no. 2021/43/B/ST10/00941.

Seagrasses are marine plants forming dense underwater meadows, which are among the most productive and valuable ecosystems on Earth. They have a long evolutionary history, descending from flowering land plants that returned into the ocean over 75 million years ago. The almost exclusively marine sediments of the Münsterland Cretaceous Basin occasionally yield plant fossils – mainly leaves from trees of the forests thriving near the coast, which were washed or blown into the sea. However, there are also fossils of angiosperms that were embedded in situ – seagrass-like plants of the order Alismatales – the only group of flowering plants with a submerged lifestyle in marine environments. Thalassocharis westfalica is the most common species of these found in late Campanian strata of Westphalia. It was first described in 1880 by the Münster-based palaeontology professor August Hosius and pharmacist/botanist Wilhelm von der Marck from Hamm, and is now serving as logo of this conference. A few isolated finds of Posidonia cretacea are also known from the area. The fossils show that a rich seagrass community already existed in the coastal waters of Westphalia and the surrounding area during the late Campanian and Maastrichtian. Given that the world’s oldest known seagrasses date from the early Campanian, the presence of well-developed seagrass communities in the late Campanian of Westphalia reflects a remarkably short period for establishing such highly diverse ecosystems. It also unveils rapid adaptive evolution of the plants as they had to quickly adapt to a saline and thus primarily hostile environment.

The upper part of the Rio da Batateira Formation crops out at the Cascata section (sensu Heimhofer and Hochhuli, 2010) and comprises a ca. 15 m thick fluvial to deltaic sedimentary rock succession of Aptian age. Eleven sedimentary rock samples have been investigated using the routine application of SEM and up to now more than 30 monocot and basal angiosperm pollen have been identified. Here, we will present LM and SEM images of various monocot and basal angiosperm pollen that have not been published previously. Amongst the numerous Clavatipollenites-, Retimonocolpites-, Pennipollis-, Stellatopollis etc. types, are a lot of pollen that are not assignable, these are either preserved as single grains or in tetrads and lumps. The botanical affiliation these sulcate pollen, except for the various Clavatipollenites types of are still unknown, however, there are sulcate and ulcerate pollen types that are surficially reminiscent of extant Arecaceae, Myristicaceae and Piperales. The remaining taxa are still enigmatic and might represent extinct early angiosperm lineages. The results of the high resolution SEM investigation of the Rio da Batateira sedimentary rocks show that the NW Brazil was one of the localities that witnessed an early diversification phase of angiosperms in the northern Gondwana realm.emphasized text

Nitrogen (N) is a crucial nutrient making up ~80% of Earth’s atmosphere. Despite this, most is in the biologically inert form N2—making nitrogen a limiting nutrient. No eukaryotes and only a few prokaryotes (<15%) possess the necessary molecular machinery to split atmospheric N2 and “fix” it to bioavailable forms. While not able to fix nitrogen themselves, certain clades of plants (including liverworts, hornworts, actinorhizal plants, legumes and cycads[MK1.1]) forge symbiotic relationships with N-fixing prokaryotes to procure nitrogen in nitrogen-poor ecosystems. The origin and drivers of the evolution/expression of this trait are not well understood. However, nitrogen-fixation in both living and fossil plants may be empirically observed using nitrogen-isotope fingerprinting (15N/14N, expressed as δ15N). Foliar nitrogen isotopes reflect their source: when it derives from nitrogen fixation this will be the atmospheric value δ15N=0, otherwise it will resemble soil (δ15N>0). Previous work using growth chambers has demonstrated that with increasing pCO2, plants exhibit greater nitrogen use efficiency (evidenced by higher foliar C/N ratios). This could imply that plants in the high-CO2 world of the early Cenozoic had less demand for nitrogen (and thus less need for nitrogen-fixing symbionts), while in the modern low-CO2 world the same taxa may require more nitrogen (and thus engage in nitrogen-fixing-symbioses). To test this hypothesis, we are comparing foliar δ15N in Cenozoic fossil specimens (n>50) and in modern herbarium specimens (n>100) to assess whether declining CO2 impacted the evolution and expression of symbiotic-nitrogen-fixation in cycads, legumes, and alders

The Amazon drainage Basin is central to understanding the evolutionary history of Earth’s most extraordinary biodiversity, which holds 40% of the remaining global tropical rainforest. The Chiribiquete Mountains in the Colombian Amazon, characterised by unique tepui-like (tabletop) formations, are strategically located at the crossroad of four major biogeographical provinces: the Guiana Shield, the Northern Andes, the Amazonian plains, and the Orinoco plains. Flora in this region is essential for decoding the phytogeography of both the Colombian Amazon and the Guiana biogeographic province, also serving as a critical component of the macro-biogeographical Andes-Amazon corridor, crucial for species connectivity. Recent geological investigations suggest that the Chiribiquete Mountains already constituted a paleotopographic high in the Early Miocene. Here we present a study of Early Miocene samples from fluvial sediments deposited in incised valleys in the Chiribiquete Mountains, and of coeval lacustrine sediments deposited westwards of the Chiribiquete Mountains. By integrating the established geological timeline with high-resolution palynological analyses, this ongoing research aims to reconstruct the paleoenvironmental evolution and phytogeographic history of the region. The anticipated results will provide critical insights into how palaeotopography influenced regional vegetation dynamics and shaped the modern biodiversity of the Amazonian biome.

The Miocene Epoch (23.03 – 5.33 Ma) represents one of the best natural analogues for future anthropogenic climate change. As a period characterised by significant climatic turnovers, higher global temperatures, and elevated CO$_2$ concentrations, it reflects climatic conditions comparable to projections of the late 21st century. While large-scale climate trends are well-documented via pollen and leaf data, high-resolution data archives into terrestrial habitat variability and local environmental stress remain poorly assessed. Fossil wood represents a crucial, yet underutilised, archive for understanding past seasonal growth dynamics and forest resilience.

We present preliminary results from samples found in the periphery of the Nördlinger Ries impact crater (southern Germany) which was formed 14.8 million years ago. The xylitic wood was preserved in the distal clay-rich Bunte Trümmermassen. These samples provide information on the vegetation composition and growth conditions in the pre-impact landscape. Our results show exceptionally narrow annual rings in gymnosperm and angiosperm woods, indicating short and unfavourable growth phases. The findings contradict traditional reconstructions of generally warm and optimum conditions in the middle Miocene. These data contribute insights to our understanding of terrestrial ecosystem responses under warm climate conditions.

The endemic Madeiran and Canarian genus Semele Kunth (Liliaceae; Asparagaceae sensu APG III) is a climber that presents broadly ovate to ovate-lanceolate phylloclades, flowers in cymes usually arising from the margins of the phylloclades, and an orange-red berry fruit. Two taxa are recognized: i) Semele androgyna (L.) Kunth, present in Madeira and the Canary Islands, and ii) Semele gayae (Webb) Svent. & G.Kunkel, occurring in the Canary Islands. Ecologically, extant taxa are associated to the laurel forests of both archipelagos, especially to the Mediterranean (dry) laurel forests. Currently, the palaeobiogeography and evolutionary timing of Semele are poorly known. Fossils that could be used to elucidate these events are unknown. Here we present the preliminary results of the first Semele fossils recovered from the new Socorridos lagerstätten at Madeira Island (Portugal), dated to Late Miocene. Fossils were obtained by deflocculating selected organic-rich sediments with 3% H2O2, washed through 1 mm and 0.3 mm screens, and stored in 70% ethanol. In total, ca. 100 fossil cuticles, stems with attached phylloclades, and partial phylloclades were recovered. Briefly, stem fossils present distichous phylloclades, ovate-lanceolate in shape, primary venation parallelodromous to campylodromous; some phylloclade specimens present marginal inflorescences with attached pedicels connected to a conspicuous submarginal vein. Overall, the described gross morphology agrees with extant Semele species. Future detailed study of the fossils and comparison with extant taxa will clarify the systematic position. Given the age and exceptional preservation, these fossils are expected to be used as calibration points for future phylogenies within Nolinoideae.

The palaeobotanical collections at the Senckenberg Forschungsinstitut und Naturmuseum Frankfurt (SF), Frankfurt am Main, Germany, are amongst the largest collections of this kind in Germany. They go back to the 19th century, and have continuously been enlarged since this time. They consist of material from regional (i.e. Hessian) localities but also from a large number of localities from all over the globe.

Besides the palaeobotanical collections proper, the SF also curates the GeoArchive Marburg, the former palaeontological-collection of Marburg University, Germany, which includes also a large number of fossil plant remains from a variety of regional but also international plant-bearing localities.

Some of the highlights of the palaeobotanical collections in Frankfurt are:
• The Messel macro-palaeobotanical collection (> 33,000 catalogued specimens)
• The Messel palynological collection
• The nannoplankton collection of Erlend Martini
• The wood anatomical collection (slides of fossil and modern plants) of Richard Kräusel
• Parts of the carpological collection of Ludwig Kirchheimer
• Macro-plant fossils from the Zechstein (Late Permian) of NW-Hesse (with the oldest figured specimens dating back to a publication by Ullmann from 1803)

The collections are open to all visitors and guest scientists with a scientific interest in palaeobotany. The lab-facilities at the SF (e.g., HF-lab, thin-sectioning lab) but also a variety of microscopic facilities (e.g. fluorescence microscopy, high-resolution macro- and micro-photography, CLSM, multispectral imaging) are also available for visitors and guest scientists working on the collections. For questions regarding the collections or visits to the collections please contact Dieter Uhl (dieter.uhl@senckenberg.de).

The Pelsa/Vazzoler fossil locality represents one of the best-preserved tropical lagoonal ecosystems of the Triassic in the Dolomites, yielding a rich malacofauna and ichthyofauna. In addition, rare laminated black limestone layers preserve a significant component of terrestrial input, including plant remains, rare insects, and traces of plant–animal interactions. A comprehensive collection strategy, independent of preservation quality, has enabled a detailed reconstruction of the terrestrial ecosystem. The plant assemblage is numerically dominated by conifers, in particular Pelourdea and Voltziales, followed by ferns and seed ferns. Fern remains are mostly preserved as isolated pinnae or pinnules. Leaves of Pelourdea are typically preserved as complete organs, only rarely folded, whereas voltzialean conifers occur predominantly as fragmentary shoots. Insect remains are rare and include four coleopteran specimens (three elytrae attributable to Archostemata and one abdominal fragment) as well as a single, well-preserved roachoid nymph, supporting a terrestrial source area. Evidence of plant–insect interactions comprises margin feeding, hole feeding, and a single mining trace, all restricted to Pelourdea leaves. In addition, a distinct endophytic damage type, expressed as small black circular structures, is interpreted as a possible indicator of fungal infection. The terrestrial assemblage preserved within the Pelsa/Vazzoler intraplatform basin most likely originated from nearby emergent areas, such as the Coldai zone (Pale di S. Martino–Civetta platform) located approximately 7 km to the northeast, or from smaller exposed landmasses distributed across the Ladinian carbonate platform system of the Dolomites.

The Permian-Triassic extinction event was the largest mass-extinction event in Earth’s history, but only very limited fossil floras have been preserved in the extremely arid environment of the Early and Middle Triassic. Here we present a unique fossil flora from the Upper Buntsandstein (Anisian, early Middle Triassic) of Üdingen, Germany.

Our locality bridges the (paleo-)geographical gap between two additional contemporary floras from Italy and the Vosges mountains. In comparison, we recognize a lower diversity in the Üdingen flora which is dominated by conifers such as Voltzia heterophylla.

The Üdingen flora contains excellently preserved specimens such as 3-dimensional female cones of Voltzia heterophylla, and a couple of partly 3-dimensionally preserved horsetail stems. Also remarkable is the presence of a horsetail branch with its leaves still attached to the node. This characteristic allows us to ascribe the horsetail fossils to the genus Neocalamites, while it was previously assumed that all Sphenophytes from this and other contemporary localities belonged to the species Equisetites mougeotii. Because of the rare occurrence of Neocalamites in the Anisian and due to the (morphological) difference(s) to other Neocalamites species reported from the Anisian of Western Europe, we have concluded the fossils from Üdingen to be a new species called Neocalamites vanderburghii. The availability of more complete plant fossils and the improved taxonomical assignment has important implications for our understanding of Triassic vegetation.

Solar ultraviolet-B (UV-B; 280–315 nm) radiation plays a fundamental role in terrestrial ecosystem processes, yet long-term terrestrial records of past UV-B variability remain limited, particularly in mid-latitude regions. This study develops and applies a chemo-palynological approach based on attenuated total reflection Fourier Transform Infrared (ATR micro-FTIR) microspectroscopy to reconstruct past UV-B flux using ultraviolet-absorbing compounds (UACs) preserved in Quercus pollen.

Methodological analyses demonstrate that ATR micro-FTIR applied to individual pollen grains or small grain clusters produces more reproducible spectra and minimizes distortion compared with conventional transmission FTIR techniques. In contrast to the widely used and highly dispersive Pinus pollen, Quercus pollen derives from more spatially constrained source areas and possesses chemically resistant sporopollenin, making it a robust and regionally representative archive of past UV-B exposure.

The method was applied to a mid–late Holocene sediment core from Crovani Pond (Corsica, France), generating the first continuous terrestrial UV-B reconstruction for the Mediterranean mid-latitudes. Variations in UAC indices closely correspond with established solar activity proxies, including cosmogenic isotopes, total solar irradiance, and sunspot numbers, as well as regional sea-surface temperature records. Major climatic intervals, such as the Medieval Climate Anomaly and the Spörer Minimum, are clearly expressed in the reconstruction.

In October 2023, new excavations in the Lebanese dysodiles (Jdeidet Bkassine, Jezzine District, Lebanon) revealed a unique Early Cretaceous ecosystem (125 Ma, Lower Barremian), providing a new perspective on the Cretaceous Terrestrial Revolution. The Lebanese dysodiles are exceptional Gondwanian deposits finely preserving fossil organisms in connection, the latter having deposited in organic rich sediments of a freshwater lake, in the vicinity of volcanic edifices. Among the preserved organisms, a remarkably diverse plant assemblage was discovered. Preservation quality is exceptional, enabling detailed investigations using tomography, geochemical analyses, and microscopy.

The description and identification of this flora aim to understand how Lower Cretaceous floras responded to climatic changes and what fossil plant assemblages can reveal about the vegetation of European ecosystems during this period. To date, no exceptionally-preserved floral assemblage from the African realm has been investigated for this key interval, leaving the composition of transitional floral communities under tropical climates largely unknown. The flora of Jdeidet Bkassine is compared with those of two comparably-preserved and coeval sites, Las Hoyas (Spain) and Bernissart (Belgium).

Preliminary results reveal the presence of previously undocumented morphologies and taxa at Jdeidet Bkassine. At least twenty embryophyte morphotypes have been recognised; the flora being dominated by gymnosperms and ferns. Despite differences in excavation methods, sampling strategies, and the field collect duration, the flora taxonomic diversity currently recorded at Jdeidet Bkassine is similar to that documented at Las Hoyas, except for angiosperms, which have been recorded hitherto only as rare palynomorphs.

Rich floras from the upper Carboniferous provide an excellent opportunity to investigate vegetation development under contrasting hydrological conditions in the vast wetland environments of the Saar-Nahe basin (Germany). Large quantities of specimen from six different sites (Camphausen, Velsen, Friedrichsthal, Göttelborn, Ensdorf and Reisbach) reveal shifting dominance of typical elements such as lycopsids, filicopsids, pteridosperms, sphenopsids and cordaites. We interpret the differences in assemblage composition as vegetation response to ambient hydrological conditions within the Saar-Nahe basin.

Vibrational spectroscopy has emerged as a versatile and powerful analytical toolkit for probing the molecular composition of modern and fossil plants, and palynomorphs. Infrared and Raman spectroscopy are non-destructive techniques providing complementary chemical fingerprints useful for answering key questions in: evolutionary paleobiology (via chemotaxonomy), paleoclimatology (via biomolecular proxies), thermal maturity assessment (via geomolecular thermometers), and molecular taphonomy (via tracking diagenetic and catagenetic alteration of biomolecules), etc. These techniques come in various specialized types—each with distinct advantages, limitations, and sampling requirements—that have benefited greatly from recent technological advances in both hardware and software. These methodological intricacies and rapid developments often present considerable barriers to researchers whose primary expertise lies outside vibrational spectroscopy, whether they are encountering these techniques for the first time or seeking to expand their existing analytical repertoire.

This poster provides: (1) a concise background on the fundamental principles of IR and Raman spectroscopy; (2) an illustrated methodological overview of specialized techniques relevant to paleobotanical and palynological research, including their respective advantages and limitations; and (3) an outlook on future research opportunities enabled by state-of-the-art vibrational spectroscopy. In doing so, it serves to accompany and provide methodological context for the talks in session 5 ("Probing biomolecules in plants and palynomorphs via vibrational spectroscopy: Methodological advancements and applications"), and includes references to the studies presented in this session and other relevant published works. More broadly, the poster aims to highlight the utility of vibrational spectroscopy approaches to inspire their wider adoption in paleobiological and palynological research.

Mycorrhizae are symbiotic relations between land plants and soil fungi that play a vital role for plant- productivity, occur in most terrestrial ecosystems and plant species, and have a fossil record dating back at least into the Early Devonian. Extant Royal Ferns (Osmundaceae) are commonly mycorrhizal, but hardly any evidence of mycorrhizae is known from the rich and diverse fossil record of this family. Here I describe a putative arbuscular-mycorrhizal fungus (AMF) found within a silicified Claytosmunda beardmorensis rhizome from Late Triassic strata of the Fremouw Formation, Antarctica. Certain roots of the specimen contain an abundance of aseptate, inter- and intracellular hyphae that grow mainly along the longitudinal axis of the root and occasionally form coils within host cells. Hyphae are irregularly swollen and constricted and vary widely in diameter, with those at the periphery of the root cortex generally being wider than those closer to the root centre. Intercellular hyphae in a specific zone around the vascular bundle produce narrower side branches that enter host cells and form repeatedly ramified structures resembling arbuscules. Occurring in the same roots are thin- and thick-walled globular structures, some with multiple wall layers, that I interpret as storage vesicles and spores of the same fungus. This find represents the oldest fossil evidence for mycorrhizal symbiosis in the Osmundaceae, and the first example of mycorrhization in fossil ferns from Antarctica. Since C. beardmorensis is one of the oldest species of crown group Osmundaceae, its mycorrhizal status indicates that AMF-symbiosis is ancestral for the group.

The Silurian and Devonian saw rapid ecological change on the Earth’s surface, going from ecosystems of thin soils, small plants and few large animals, to those of deeper soils, the first trees, and the first terrestrial vertebrates. But many of the most abundant organisms of the Silurian and Devonian do not have close extant relatives. These include early land plants, like the rhyniophytes and the zosterophylls, and the nematophytes, whose placement in the tree of life has been extensively debated. In order to better incorporate these organisms without clear parallels in extant lineages into our understanding of early terrestrial ecosystems, the traits of these organisms must be understood in greater detail. Using the exceptionally preserved Early Devonian fossils of the Rhynie chert, I have applied confocal laser scanning microscopy, a form a superresolution imaging, to these early land plants and nematophytes. This technique allows novel anatomical and structural details of these enigmatic organisms to be uncovered. A better understanding of the ecologically relevant traits of these key organisms will provide major insight into Silurian-Devonian terrestrial ecosystems, and improve the accuracy of ecological models of this time period.

Based on a detailed study of peat-forming plant communities and their pollen record (Henriet et al., in press), a study was conducted on fossil pollen to identify past human impacts on peatlands and to understand the local vegetation dynamics of such communities. The study focuses on two cores from two peatlands located in the southern edge of the French Massif Central: the Canroute peatland (Monts de Lacaune, Tarn, France) and the Nassettes peatland (Mont Lozère, Lozère, France). Using precise chronological control (16 and 15 radiocarbon dates, respectively), we have found that both peatlands initiated during the Late Glacial Interstadial, which is exceptional compared to the other peatlands in the region.

The Canroute peatland is one of the most remarkable peat-forming habitats of the studied area. It harbours a high plant species richness and several rare species, including some with strong oceanic affinity. The second peatland studied, the Nassettes, is among the largest peatlands in the Cévennes mountains. It is located at the interface between Atlantic, Mediterranean and continental influences. Its vicinity to ancient anthropogenic activities makes it an interesting site for studying the impact of human activities on local vegetation. The pollen record shows that both sites evolved mostly according to the hydroseral succession. Although, several indices of human activities such as Plantago, a well-known grazing pollen indicator, are recorded as irregular occurrences since 7000 cal. BP in Canroute and 6000 cal. BP in the Nassettes, could reveal the first local impacts of agropastoral practices in the Neolithic period.

Archaeology uses palynology to study past human-landscape interactions. Truly quantitative vegetation reconstructions of archaeological sites and landscapes are crucial for this research, but these are notoriously difficult to obtain from fossil pollen records. Recent advancements in palynological modelling methods like the Landscape Reconstruction Algorithm (LRA) provide an important step forward. Here I present an exceptional case study of the Middle Palaeolithic site Neumark-Nord 2 (Sachsen-Anhalt, Germany). At this site, Neanderthals were present semi-permanently for ca. 1500 years in the early temperate Eemian, 125 ka ago. By applying the LRA with different input parameter values of relative Pollen Productivity Estimates to Neumark-Nord 2 and three neighbouring sites, the plausible range of past vegetation composition was reconstructed in detail on the regional (50 km) and local (200 m) scale during the period of Neanderthal habitation. The regional vegetation consisted mostly of light forest, with small elements of open land and closed-canopy forest, similar to reconstructions based on pollen percentages alone. The local vegetation was almost completely open with only some trees, contrary to the pollen percentages that suggest dominance of light forest. The quantitative vegetation reconstructions are partially different from qualitative reconstructions based on other palaeoecological proxies, thus showing the importance of a combination of quantitative modelling methods and qualitative approaches to better interpret palaeoecological and archaeological datasets. The approach used here shows that the LRA can be applied to non-Holocene archaeological sites to provide new insights into hominin-landscape interactions at high spatial and temporal resolution.

Conifer leaves can be significant components of fossilized macrofloras and besides being evidence of species presence in the assemblage, they may also contain information about the local paleoenvironment. To strengthen paleoenvironmental inferences based on fossil leaves, we wish to better understand the morphological variability of extant conifer needles. This study focused on three members of the Cupressaceae: Metasequoia glyptostroboides, Sequoia sempervirens, and Taxodium distichum. Mature trees of each species were sampled across the city of Vienna, Austria. Each tree was repeatedly sampled on its most shaded and most sun-exposed sides at one-meter intervals up to 10 meters in height during the spring and summer of 2025. Macromorphological and micromorphological measurements of c. 500 individual branchlets were statistically evaluated to reveal any potential effects of light exposure and (mild) hydraulic gradients. Macromorphological observations indicate that variation is driven by light exposure and canopy position, which supports the continuation of analysis of associated stomatal responses. Disentangling height- and light-related morphological and stomatal variation has the potential to improve paleo-environmental and paleo-CO₂ reconstructions, as well as to enable the confident identification of fossils and sun-needle morphotypes.

Reconstructing past continental climates is a major objective in palaeobotany, and fossil plants constitute one of the most effective proxies for this purpose. Paleoclimate reconstructions using fossil leaf assemblages can be based either on taxonomic affinities or on physiognomic approaches. These approaches rely on relationships between leaf morphology and climate established from modern calibration datasets. However, the quality of the results obtained through physiognomic approaches depends heavily on the climatic coverage of the current calibrations. While the CLAMP (Climate Leaf Analysis Multivariate Program) method relies on extensive modern datasets comprising more than 370 sites worldwide, several climatic regions remain underrepresented, especially Mediterranean climates. In contrast, for other plant organs, especially wood, the associated methods and calibrations still need to be developed. Here, we present two studies addressing these calibration challenges. First, we explore ways to improve CLAMP climatic reconstructions through the addition of 11 new sites, mainly from Mediterranean environments. Second, we present a preliminary study toward the development of a wood–climate calibration dataset based on three plant groups sampled from field collections and the Montpellier xylarium, including material from Brittany (France), sub-Saharan Africa, and French Guiana. These two studies provide an opportunity to discuss broader methodological questions related to palaeoclimatic calibrations, including the number and climatic distribution of calibration sites, specimen selection strategies, and data collection protocols.

The morphological diversity of pollen grains can provide important information about several aspects of plant science. The pollen morphological database remains scarce in this eastern and western Himalayan province of the Indian biogeographic zone, despite the rich diversity of angiosperms. The detailed pollen morphometry of various plant taxa from the western and eastern Himalayan region will enhance the palynological database of the Indian Himalaya. Light compound microscopy (LM) and scanning electron microscopy (SEM) were employed to identify and characterize pollen grains. Based on the qualitative and quantitative morphological data of 132 angiosperm species from 58 families, statistical analyses (principal component analysis, cluster analysis, and correlation analysis) were performed, explaining the phylogenetic relationships among these families. In addition to their interrelationships, these morphological data also provide insights into the primary pollination modes (entomophily or anemophily) and the evolutionary trends of pollen grains in these families. Besides, pollen morphological data for endemic angiosperm species, along with data from other families, could provide preliminary insights into vegetation and palynology in the eastern and western Himalayan landscape of Indian subcontinent.

Plant macrofossil-preservation potential (PMPP) is restricted to a limited number of depositional environments (EOD). In turn, the record’s quantity and quality are dictated by biological and geochemical factors operating therein. Outcrops present a continental stratigraphy of stacked, laterally contiguous landscapes. Each overlying landscape has similar, but spatially offset, EODs. Their distribution is controlled by the (1) original fluvial systems and associated floodplains, and (2) following exposure, subsequent erosion resulting in an outcrop’s extent and accessibility from which material may be studied.

Often interpretations of ecosystem-and-vegetation response over various stratigraphic thicknesses are based on few, coarsely correlated stratigraphic sections. An underlying, and implied, assumption exists that there is an equal probability to find fossil assemblages in each superposed landscape. Various degrees of ecological perturbation are invoked to explain the absence of macrofossils from the record over decimeter to decameter intervals. Yet, such interpretations may be unwarranted.

Theoretical test results are presented on the probability of crossing one or more EODs across 500, 20 km-long transects in four 502 km modern equatorial localities. The frequencies of water (high PMPP) versus non-water (low PMPP) pixels were determined using the Copernicus Database Ecosystem in one limnic site (Lake Mai Ndome, DRC) and three fluvial regions (Santa Bábara and Japurá Rivers, Amazonia; Kawatngwa, Papua New Guinea). The median value of water controlling preservation, a very low probability exists that a “continuous” record can be obtained from limited stratigraphic sampling, biasing interpretations of ecosystem dynamics.

Lichens are generally very rare in the fossil record. Baltic and Bitterfeld ambers are notable exceptions, with hundreds of specimens discovered to date. The fact that the tree resin preserved lichens and associated organisms lifelike in their microhabitats provides reliable insights into structure and composition of Paleogene lichen communities and their interactions with other organisms. The associations include a wide range of growth forms, and the thallus morphologies are in line with a relatively humid and most likely temperate climate of the amber source forests. Symbiotic propagules such as isidia or soredia occur in many amber-preserved taxa, showing that concurrent dispersal of mycobiont and photobiont has a long and successful evolutionary history. Survey of exceptionally large amber specimens with enclosed corticolous communities revealed that crustose lichens were ubiquitous. Although crustose thalli are not readily identifiable in most cases, we confirmed their presence based on well-preserved apothecia, isidia, and frequently associated lichenicolous fungi. Contrarily, competitive large foliose lichens are rare which allowed a number of small delicate foliose and fruticose lichen taxa to share these habitats. Lichens possessing cushion-like spongiostrata on the lower surface of the thallus were very abundant in the European Paleogene amber forests. Such taxa are absent from continental Europe today, pointing to substantial change in the composition of lichen communities within the past 35 million years. Evidence of grazing damage is rare in the fossils, and actualistic experiments pointed to molluscs and mites as grazers of Paleogene foliose lichens.

Late Eocene Baltic amber represents the largest amber deposit worldwide. It has been studied for centuries, but plant inclusions are comparatively scarce and the angiosperm diversity of the Baltic amber source area is still insufficiently understood for a holistic reconstruction of the amber forest. Here we describe three well-preserved flowers analyzed with high-resolution X-ray tomography (µCT) and synchrotron radiation-based micro-computed tomography (SRµCT). These non-invasive methods make it possible to visualize morphological details that are not visible using just light microscopy. Two fossils comprise a corolla and diplostemenous androecium forming a distinct shallow floral ring. They share long ribbon-like antepetalous staminodia and fertile alternipetalous stamens with a distinctive H-valvate anther dehiscence and elongated connective extensions. The third fossil consists only of the androecium. Using the morphological analyses complemented by phylogenetic approaches, the fossils were retrieved within the Hamamelidaceae (Hamamelidoideae, Saxifragales) and may represent a morphological intermediate between the Late Creataceous Androdecidua endressii Magallón, Herendeen et Crane and flower morphologies of extant members of the family. Our fossils are the first unequivocal Baltic amber record of the family, they also increase the known floral diversity of the family and add to their sparse fossil record of well-preserved flowers.

Worldwide, oceanic islands are known to harbour unique floras and vegetation types. Within Macaronesian archipelagos, one of the most emblematic ecosystems are the evergreen broad-leaved Laurel forests. These were, since the mid-19th century, based on an extensive continental fossil record, considered an impoverished relict of extinct taxa that once occurred during the Cenozoic of Europe. This view was long held until recently, when molecular dating advocated a recent, i.e., Pleistocene origin of many of the plant taxa present in these insular forests. However, these contradicting biogeographical/evolutionary hypotheses (i.e., relict vs. recent) can be tested if deep-time and palaeobiologically informative fossils are found within Macaronesian Islands. Here we report, based on insular volcanostratigraphy, 40Ar-39Ar dating, and palaeobotanical data, a new Late Miocene lacustrine fossiliferous locality, the Socorridos Lagerstätte, from Madeira Island, Portugal. The fossils are morphologically and anatomically preserved as mummified/lignified leaves, flowers, anthers, fruits, seeds, wood fossils and include charcoalified woods. Leaf and flower fossils provide direct palaeoecological evidence of a Laurel forest composed by Laurus sp. and Ocotea sp. already established in the Late Miocene of Madeira Island. Furthermore, the palaeoflora includes the presence of currently endemic representatives within the families Asteraceae, Apiaceae, Boraginaceae, Brassicaceae, Lamiaceae, Campanulaceae and Ericaceae to name a few. In this talk we briefly explore the conflicting results obtained from the Socorridos fossils and phylogenetic studies, pointing to the need of the detailed study and integrative deep-time plant fossils record to fully understand the plant evolution on islands.

A major global cooling during the Middle Miocene Climate Transition, ~ 14–13 million years ago (Ma) marked the beginning of a shift between Earth’s coolhouse and icehouse states. During this time, much of Central and Southern Europe was covered by a northward extension of the Mediterranean Sea, the Central Paratethys. Remarkably, the Middle Miocene (~ 12.7–12.1 Ma) Lagerstätte of Radoboj from northern Croatia comprises a hyperdiverse flora and insect fauna along with fish, dolphin and bird remains deposited in marine sediments. Both the flora and insect fauna of Radoboj were first published in the middle of the 19th century. In this talk, I first introduce the rich fossil flora of Radoboj and discuss taphonomic and taxonomic aspects of this plant assemblage. I then briefly present the insect remains and plant-insect interactions recorded on fossil leaves. Our quantitative palaeoclimate reconstructions using leaf physiognomy as a climate proxy suggest near-tropical conditions on an island surrounded by a warm sea, despite global cooling trends. Modern environments with similar climate conditions are found on Okinawa Island and along the northern coast of the Gulf of Mexico. Notably, modern climate stations are at the border between warm temperate (C) and equatorial (A) Köppen-Geiger climate types. The richness of plant-insect interactions in this assemblage is unparalleled for most of the Cenozoic of Europe indicating high ecosystem productivity. Our findings underscore the importance of land-sea distribution in modulating regional terrestrial climate and latitudinal gradients and have significant implications for understanding vegetation responses to climate change.

Leaf epicuticular waxes form the outermost protective layer of leaves and reflect adaptations to environmental conditions. Their morphology and chemistry is usually not well preserved in the fossil record but can be under specific circumstances, providing information for paleoclimate reconstruction and taphonomic histories of leaves in lignites. Whitish fossil layers on Eocene leaves have been interpreted as preserved epicuticular waxes, although an alternative hypothesis suggested secondary ex situ accumulation of waxes derived from the surrounding lignite. Here, we investigate the late Eocene leaves of the fossil-species Eotrigonobalanus furcinervis and Daphnogene cinnamomifolia, both exhibiting whitish wax layers. (1) Scanning electron microscopy (SEM) revealed taxon-specific wax morphologies. E. furcinervis shows vertically oriented non-entire platelets, whereas D. cinnamomifolia exhibits horizontally stacked hollow platelets. Recrystallization experiments demonstrated differences in platelet shape and size, with 1–2 µm valley-shaped platelets in E. furcinervis and 3–7 µm medially ridged valley platelets in D. cinnamomifolia. (2) Preliminary gas chromatography-mass spectrometry (GC-MS) analyses indicate differences in chemical composition, with dominant long-chain C28 and C30 fatty acids in E. furcinervis and C28 and C30 alcohols in D. cinnamomifolia. The observed taxon-specific morphological and chemical patterns disagree with ex situ wax accumulation from the surrounding lignite and instead support in situ preservation of modified but taxon-specific epicuticular wax structures. Furthermore, examination of more than 1500 fossil leaves revealed significantly stronger whitish layer formation on abaxial leaf surfaces, consistent with the in situ hypothesis. These findings highlight the potential of fossil wax preservation as a proxy for paleobotanical and paleoenvironmental reconstructions.

Historical fossil collections are of fundamental importance for biological and palaeontological research. It is often assumed that such old collections have already been studied so thoroughly as to leave little to be discovered. However, with the advent of new methodologies, such as X-ray tomography, epifluorescence, or Confocal Laser Scanning Microscopy (CLSM), it is now possible to retrieve more information from historical specimens often in a non-destructive manner, leading to unexpected insights and hypotheses on already described and studied material.
Here, I will present a few examples of new methods allowing the reinterpretation of historical material, focusing on fossils from the Early Cretaceous of Argentina and North America. In particular, I will show the potential that epifluorescence and CLSM have in resolving the affinities of fossil foliage and in discovering new structures in situ, such as in planta resin or thin or fragile cuticle that is impossible to obtain via traditional maceration techniques. I will then discuss the implications that these new discoveries have for material present in collections around the world, and how many new findings are still hidden on collection shelves.

The Big Sand Draw fruit and seed flora of the Paleocene Fort Union Formation in the southern Wind River Basin of Wyoming, USA, was initially collected in the 1960s. However, the specimens were only preliminarily studied because of the difficulty of understanding the morphology of disseminules preserved predominantly as moulds. We investigated 161 hand specimens of the highly fossiliferous sideritic sandstone, ranging from 1 to 12 cm in maximum dimension, using a GE Phoenix V|tome|xm 240 micro-CT scanner, and processed resulting image stacks with VG Studio-Max, Amira, and Meshlab software. While some disseminules were exposed at the surface, the majority of the samples contained one or more (up to 45) fruits or seeds hidden inside that were revealed only by this X-ray methodology. Our current inventory of the fruit and seed flora includes about 55 morphotypes. These include Ditaxocladus (Cupressaceae), Palaeosinomenium (Menispermaceae), Eotrochion (Trochodendraceae), Platanus (Platanaceae), Hexagonokaryon (Fagaceae), Cranea (Betulaceae), Kingsboroughia (Sabiaceae), Cyclocarya (Juglandaceae), Acer (Sapindaceae), Ampelocissus (Vitaceae), Cornus (Cornaceae), Langtonia, Mastixia, Mastixiopsis (Mastixiaceae), cf. Rehderodendron (Styracaceae), Sandrawia (Ericaceae), Iodes, and Palaeophytocrene (Icacinaceae). At least 30 additional, morphologically distinctive fruit and seed taxa remain unplaced within the Eudicots. The technology allowing us to "see inside" the samples has revealed greater species richness and more details of morphology than were previously known and, together with co-occurring leaf impressions, contributes to an improved understanding of the forest composition, paleoenvironment and biogeographic affinities of this flora. This work also informs us that specimens traditionally bypassed in fieldwork ​may be paleobotanically significant.

It is in the best interest of any field to ensure that cutting-edge analytical tools remain both user-friendly and accessible to the broader scientific community. As fossil plants are increasingly utilized in deep-time climatology, the deployment of web-hosted tools (such as ‘CLAMP Online’) and R packages (such as DiLP) has paved the way towards an era in which any palaeobotanist, regardless of methodological expertise, may contribute meaningfully to our knowledge of Earth’s ancient climates. Here, we present a new tool that allows users to perform nearest living relative palaeoclimate analyses through interaction with a simple interface. Users enter a list of extant taxa, after which the climatic envelope of each taxon is imported from our database and the most probable climate in which all taxa co-occur is determined using a probability density approach. Separately, our tool also allows users to input palaeoclimatic variables obtained from other proxies and calculate a conservative ensemble result. This is achieved through unweighted Monte Carlo resampling utilizing the mean and standard deviation of each variable, allowing for the generation of conservative ensemble palaeoclimate estimates. By creating this tool, we aim to improve the accessibility, usability, and deployment of nearest living relative and ensemble palaeoclimate methods, which are currently underutilized when compared to leaf physiognomic palaeoclimate analyses.

Reconstructing the height of ancient trees is crucial for understanding fossil forests in three dimensions, yet modelling ancient height–diameter relationships remains difficult because the trunks of fossil trees are usually fragmentary and rarely preserve their full height. Building on a previously developed growth modelling framework for ancient araucarian trees, we extend this approach to Pinaceae, the largest living conifer family and an important component of Mesozoic and Cenozoic floras. We compiled height–diameter data for 2,530 living Pinaceae trees representing Abies, Larix, Picea, Pinus, and Pseudotsuga from nine populations in Denmark, Türkiye, China, and Mexico. Twenty nonlinear height–diameter models were evaluated. Initial Akaike Information Criterion comparisons revealed substantial population-specific variation in model support. Twelve models satisfying the screening criteria were subsequently fitted to 100 balanced random samples, from which ten median models were retained for detailed evaluation using RSS, RSD, RSE, RMSE, and AIC. Across the nine equally weighted populations, the median Logistic model showed the best overall composite performance and was therefore selected as the generalized family-level model for Pinaceae. This model was applied to 26 standing Miocene pinaceous trunks from Lesvos, Greece, and yielded heights between 22.2 and 25.3 m, with a mean of 25.3 m. Our results provide a robust empirical framework for reconstructing the stature of ancient Pinaceae trees and highlight the value of generating height–diameter models for living analogs for extrapolation to fossil trees.

Biocodicology is the recently emerging field that aims to analyse the proteins and DNA of medieval manuscripts, originally focused on historical parchments. Here we present a summary of our three-year-long research extending the field of biocodicology into a novel direction of complex palaeobotanical and molecular multi-proxy studies aiming not only for identification of the plants as writing supports, but also for revealing the provenance of the plant-based manuscripts whose origin is not known or dubious. We study 14th-19th century-old palm-leaf manuscripts (PLMs) looking at the micro- and nano-layers of non-palm plant traces (e.g., micro-fragments of plant tissues, ash, phytoliths, and plant DNA traces) accumulated on the surfaces of the folios during their preparation, historical and contemporary preservation efforts, storage and handling. PLM production used to be a complex multi-step process that involved a wide number of area- and culture-specific plants; these, however, were never properly documented neither geographically nor chronologically. Little is known about the botanical and ethnobotanical aspects of this practice, as well as about the rationale for choosing certain plants. At present, this craftsmanship is almost completely eliminated, therefore the only way left to study PLM material history is palaeoecological reconstruction. Our studies introduce a novel analytical framework combining laboratory and metadata-based approaches to material analysis, provenance and production history of PLMs. Combining methods of life and natural sciences with textual and script studies, we work toward a comprehensive understanding of PLMs as both archives of their own history and novel sources of ethnobotanical and palaeoenvironmental data.

Biofilms promote the preservation of organic material by encasing decaying tissues, forming a protective matrix over soft tissue, facilitating mineral precipitation, and slowing down decay. Despite numerous studies on the influence of microbial biofilms on animal fossilization, little is known about the role of microbial biofilms on leaves that may lead to the formation of leaf compressions. However, with genomic sequencing and bioinformatic analyses, it is now possible to identify and characterize the microbes involved in leaf biofilms, as well as to document shifts in community composition under different environmental conditions. Here we present a series of a dozen decay experiments investigating the role of bacterial taxa, sediment types, and oxygen conditions on leaf biofilms in natural freshwater pond conditions or in lab aquaria, which we carried out over the course of five years. We ran the decay experiments with Equisetum shoots and the foliage of ferns, Ginkgo, conifers, water lilies, evergreen and deciduous dicots, including green, yellow, and red pigmented leaves. Analytical tools and bioinformatic analyses were applied, including sequencing (16s rRNA, ITS, metagenomics), light microscopy, SEM, EDX, ASV richness, Shannon Index, NMDS statistics, ordination plots, correlation plots, and Venn diagrams. In summary, biofilms readily form on all freshwater-submerged leaves, although some taxa naturally produce thicker biofilms. Biofilms rapidly shift in taxonomic composition over days and in response to substrate, oxygen conditions, and water chemistry. Good promoters of biofilm production and incipient mineralization are the bacterial genera of Desulfovibrio, Tolumonas, Shewanella, pond mud, montmorillonite clay, and anaerobic conditions.

The medullosans depict widespread and diverse floral elements of late Paleozoic tropical landscapes on the Northern Hemisphere. In the phylogeny of the seed-plant clade the group holds a poorly constrained position, as its numerous ancient features complicate comparisons with modern relatives. Among these features, the medullosan stele is of key significance as it exhibits a complex and uncommon arrangement of vascular elements that varies distinctly among the known taxa. These include a variously dissected vasculature, clustered primary xylem zones, centripetally and centrifugally growing secondary xylem assigned to the manoxylic wood type, central accessory strands, and a kind of polyxyly recently documented for some taxa. Regarding the primary vascular organisation, there exist some parallels to siphonosteles of the Polypodiopsida, thus contradicting the concept of a eustele that is thought to be apomorphic to the seed-plant clade. Nevertheless, collateral bundles are present in the leaf vasculature of medullosans. By analysing new anatomical data on the diversity, ontogeny, and functionality of medullosan stem vascular architecture, we present new perspectives on the stelar evolution of ancient seed plants and their highly specialised growth models that were supposedly outcompeted at some point in transition to the modern seed-plant flora.

Fossil plants from the interval of the uppermost Permian and lowerest Triassic succession of western China provide a means by which to assess the impact of the end-Permian mass extinction in the mid-latitudes of NE Pangaea. Here we describe a petrified forest from the uppermost part of the Wutonggou Formation in Xinjiang Autonomous Region, northwest China. The age of the fossil interval is the latest Permian (251.06 ~ 251.93 Ma), which are constrained by a number of geochronometric ages (ID-TIMS). Both allochthonous and autochthonous trunks with roots penetrating downward to the underlying palaeosols, are excavated. They are preserved in lacustrine deltaic deposits, and are explained to be a lakeshore foest that was buried by lake transgression. Anatomical analysis shows that the canopy of the forest is composed of at least four types of gymnosperms (Agathoxylon sp., Septomedullopitys sp., Protophylloocladoxylon sp., Zhuotingoxylon liaoii) and one type of calamitalean (Arthropitys sp.). Both marcro-fossil and palynological evidence testified that it was a gymnosperm-dominated forest. Fungal-plant, arthropod-plant, plant-plant interations have been observed from the petrified trunks, demonstrating a complex vegetational ecosystem around the lake. During the time when the forest alive, the end-Permian mass extinction event wiped out ~90% of marine species which were constrained to a short interval of ~60 kyr. Our finding of the latest Permian forests provides a rare window into how the largest biotic crisis in Earth’s history unfolded on land.

Key words: Changhsingian; fossil trunks; nurse logs; fungal hyphae; coprolites; palaeoecology

Cordaitales represent an extinct group of cosmopolitan gymnosperms with a chronostratigraphic range from the Mississippian to the Permian. These plants are commonly interpreted as having monopodial trunks that reached considerable heights before developing a crown of branches bearing sessile, elongated leaves often arranged in a spiral pattern. The group includes arborescent forms, known from tropical Pennsylvanian deposits that frequently exceeded 30 m in height, as well as smaller forms, including scrambling shrubs and small trees. Cordaitalean axes exhibit a particularly complex internal structure concerning their pith, which may be septate and parenchymatous in mature plants. Although less frequent, such kind of pith also occurred in other Paleozoic plants, making the taxonomic assessment of isolated pieces of wood challenging. Despite the recurrence of septate and parenchymatous piths among Paleozoic paleoxylofloras, their structural organization, maturation, and possible functional significance in cordaitalean axes remain poorly understood. This study investigates the anatomical structure of the pith in cordaitalean axes based on classical literature and fossil material from the Permian fossil forests of Chemnitz in central Germany and the Parnaíba Basin in northeastern Brazil. Based on the available literature, studies on connected organs, seven samples previously classified as Cordaixylon Grand'Eury 1877 from the Parnaíba Basin, and one specimen from the Chemnitz Basin, we conducted a detailed analysis of pith types in Cordaitales, aiming to better understand pith composition, ontogeny, and possible functional implications. The recurrence of septate piths among distinct Paleozoic gymnosperm groups raises the possibility of convergent anatomical responses associated with similar paleoenvironments.

The Late Pliocene (Brunssumian – Reuverian) lignite-bearing deposits of the Wölfersheim Formation in the Wetterau region (Hesse, Germany), have long been known for their abundant and diverse macrofloral (i.e., carpological remains) and palynofloral assemblages. Although the (in some layers massive) occurrence of charcoal has been repeatedly reported from these deposits since the middle of the 19th century, no in-depth studies of these remains have yet been undertaken. Charred wood remains from the former Wölfersheim open-pit mine, curated in the palaeobotanical collection of Senckenberg in Frankfurt, have been analysed by means of Scanning Electron Microscopy to investigate the anatomy and taxonomy of the wood that was part of vegetation affected by palaeo-wildfires during the time of deposition. All charcoal specimens analysed so far exhibit a similar wood anatomical pattern, comparable to that of the fossil-taxon Taxodioxylon. Traces of pre-charring microbial interactions within the wood (i.e., charred fungal hyphae and “shot-like” holes) occur in several specimens, indicating that at least part of the analysed charcoal assemblage most likely originated from logs or twigs of already dead and decaying wood that were subsequently affected by ground or surface fire consuming litter on the forest floor. However, one charcoal specimen displays a peculiar pattern of fungal colonisation, with hyphae forming mycelia within ray cells. This feature indicates colonisation of still living plants by specialised parasitic fungi prior to charring.

Several islands in the Aegean Sea are known for their fossil forests. Renown are the so-called petrified forests of Miocene age on the island of Lesvos, Greece, consisting of a stunning number of upright tree trunks, fallen logs, pieces of wood, and leaves on the western part of the island. The fossil trees were buried in situ in tephra by multiple eruptions in the early Miocene. Studies on the standing trunks, wood, and leaves show that mixed forests of conifers and angiosperms flourished on Lesvos some 20 million years ago. While most conifers have already been identified, little is known about the woody angiosperm flora. Here we present the identification of several angiosperm and conifer woods from various localities in western Lesvos. This wood flora consists of ca. 40 specimens, representing, among others, Lauraceae, Nyssoxylon, Populoxylon, Fagaceae, and Lesbosoxylon. Among the lauraceous woods, we have identified well-known species such as Laurinoxylon czechense, as well as a new species of Laurinoxylon with numerous tiny crystals. Populoxylon wood with exclusively uniseriate rays represents another new species. Completely new to the flora is the family Nyssaceae, which went extinct in Europe in the Pliocene. The fagaceous wood is distinctive, with very wide and high rays of over 1 mm in height. Lesbosoxylon paradoxum and L. pseudoparadoxum have already been described from Lesvos, but we document new occurrences, expanding their distribution on the island. Our results provide deeper insight into the lauraceous-dominated angiosperm flora in the mixed forests growing on Lesvos during the Miocene.

Rivecourt and Le Quesnoy (Oise, France) are two fossil sites located in the northeastern part of the Paris Basin that have yielded very rich floras and faunas. Rivecourt is dated to the uppermost Thanetian and Le Quesnoy to the lowermost Ypresian, making these sites particularly suitable for investigating vegetation changes across the Paleocene-Eocene Thermal Maximum in Europe. In addition, the two deposits represent contrasting paleoenvironments: Rivecourt corresponds to a meandering river system associated with a subtropical forest whereas Le Quesnoy represents a fluvio-lacustrine subtropical wetland.

Approximately 40 hardwood and stem specimens from each site were prepared as thin sections from resin-embedded wood fragments and described using light microscopy and IAWA terminology. The Le Quesnoy assemblage is anatomically homogeneous and dominated by diffuse-porous woods characterized by simple perforation plates, alternate intervessel pitting, rays uni- to triseriate and randomly distributed vessels commonly forming short radial multiples. In contrast, Rivecourt assemblage displays greater anatomical diversity, including fagalean-type woods with exclusively solitary vessels radially arranged, woods with scalariform perforation plates and very small vessels, as well as comparable to those of Le Quesnoy. The Arecaceae of both sites are likely similar.

Both assemblages are taxonomically diverse and mainly resemble extant tropical families, such as Sapotaceae, Combretaceae, Rubiaceae, Sapindaceae, Rhamnaceae or Coryphoideae. These results provide new insights into the composition and ecological structure of European subtropical forests across the PETM and will be compared with other plant organs from both sites.

Lepidodendron aculeatum is an arborescent lycopod that populated the vast coal swamps in north-western and central Europe during the Late Carboniferous (Serpukhovian–Moscovian) dominating the lush vegetation of tropical wetlands. Not only was the species the most prominent producer of the thick coal seams mined in those areas for the last centuries, these up to 40-m-tall plants also represent the most iconic fossils of the Upper Carboniferous. Lepidodendron aculeatum is known predominantly from trunks and fragments of trunk/branch surfaces, or external moulds, with their characteristic leaf scars (‘scales’), but articulated fossils are very rare. Here, we present a 4-m-long, articulated branch system – a partial crown – of Lepidodendron aculeatum, as well as further excellently preserved fossils of trunks/branches with attached leaves, and possible conspecific strobili and sporophylls preserved with particular anatomical details, from the Bashkirian fossil lagerstätte of Hagen-Vorhalle in NW Germany. Based on the described fossils, we emend the diagnosis of Lepidodendron aculeatum and add information to the common perception of the reconstruction of these iconic arborescent plants. Furthermore, we present the reconstruction of a display model of the canopy of Lepidodendron aculeatum in 1:1 scale, created for the current exhibition of our museum.

Marattialean tree ferns were major components of tropical wetland forests during the late Paleozoic. Fossil record of isolated organs is extremely rich, but most of them are morphspecies (e.g. Pecopteris) which covered the actual diversity of this group. The T0 fossil Lagerstätte known as Permian “vegetational Pompeii”/ Wuda Tuff Flora, has yielded numerous organically connected organs of Marattialean tree ferns. Here we present a whole-plant reconstructed marattialean tree fern Eoangiopteris congestus based on exceptionally preserved fossil materials from this locality. The plant is reconstructed as an arborescent fern (reach up to 7.8 m) with an upright Psaronius-type stem surrounded by a thin root mantle and topped by an apical crown of compound fronds. Fronds are tripinnate and pecopterid, whereas fertile pinnules assigned to Eoangiopteris and bear Apiculatisporites-type microspores. The oblong vegetative pinnule with decurrent midvein and once-bifurcated lateral veins can be compared with Pecopteris orientalis. Cabbage-shaped Aphlebiae occur in pairs and organically attached to petioles. Claupteris-type leaf scars and Stipitopterid rachis are also reported. Following Scolecopteris libera, current species represents the second whole-plant reconstructed Marattialean tree fern, and offers important insight into the diversity, growth habit, and ecological role of tree ferns in Early Permian peat-forming forest ecosystems of North China.

Lycopsids, a monophyletic lineage of vascular plants originated in Late Silurian-Early Devonian, reached peak diversity as arborescent forms during Carboniferous-Permian, dominating tropical wetlands and contributing 50-90% of peat-forming biomass. Despite abundant fossil records, their biology such as gross morphology, ontogeny and lifespan remains poorly understood. Here, we present the first whole-plant reconstruction of Sigillaria sp. nov., based on exceptionally well preserved fossil trees from the Wuda Fossil Site, also called Chinese “Vegetational Pompeii”, recently designated as one of the Second 100 IUGS Geological Heritage Sites. The reconstruction reveals: (1) columnar trunk with a terminal crown formed by leaves and whorls of lateral pedunculate bisexual strobili bore megasporangia basally and microsporangia apically; (2) early ontogeny established mature basal diameters through a broad proximal primary body with thick primary cortex, thin vasculature, and thin periderm, a body plan that persisted with only minor distal tapering, as negligible secondary thickening displaced the primary inner cortex rather than driving radial expansion; meanwhile limited phloem indicates most photosynthate was used locally for apical growth, periderm production, and sporangia/spore development, with minimal long-distance translocation, resulting in largely self-sustaining organs throughout the plant; (3) potentially greater longevity based on growth increments between reproductive zones and transition of young and old leaves; (4) rooting system Stigmaria on the substrate before in the substrate.
Keywords: reconstructed whole-plant, Sigillaria, ontogeny, lifespan, Early Permian

Pagiophyllum (Heer, 1881) is a form genus of extinct fossil conifers ranging from the Late Permian to Late Cretaceous, frequently allied with the family Cheirolepidiaceae. Most records consist of fragmentary shoots lacking cuticles and reproductive organs. Among these fossil records, Pagiophyllum maculosum Kendall is a remarkable species initially described from the Middle Jurassic of Yorkshire, UK, but lacking cuticle morphology and reproductive structures. Here, we report the first occurrence of P. maculosum from the Early Jurassic of western Hubei, South China. Well-preserved specimens with attached reproductive structures confirm its assignment to the Cheirolepidiaceae. The material includes leafy shoots with cuticles, male cones, and seed-bearing female cones. Penultimate and ultimate shoots bear helically arranged leaves (2–3 parastichies). Leaves are hypostomatic, with stomata in distinct rows and no epidermal papillae. Stomatal complexes are elliptic with 4–6 subsidiary cells; epidermal cells range from rectangular to irregularly polygonal. Female cones are elliptical, comprising 36–40 helically arranged bract-scale complexes. Pollen cones are subspheroidal with peltate microsporophylls. These specimens provide detailed morphological and anatomical features, thus permit a whole-plant reconstruction. Beyond taxonomy, P. maculosum offers key paleoclimatic insights. Thick cuticles, sunken stomata, and reduced leaf areas reflect a systemic xerophytic adaptation to minimize transpiration and conserve water. Associated floras dominated by gymnosperms (e.g., ginkgoaleans, bennettitaleans) and the near absence of hygrophilous ferns indicate an arid to semi-arid climate condition during deposition.

Excellently preserved, articulated plant fossils from the Oxfordian (Upper Jurassic) Tochikubo Formation in Northeast Japan provide critical insights into the diversity and reconstruction of whole-plant bennettites. Based on these discoveries, two distinct taxa were most recently described and reconstructed. First, Ohaniella ptilofolia gen. et sp. nov. is established based on preserved axes with attached Ptilophyllum jurassicum-type foliage and apical ovuliferous structures. The co-occurrence of Weltrichia-type microsporangiate flowers suggests they were shed after maturity, and that O. ptilofolia likely formed monotypic shrub thickets under specific environmental conditions. Second, Kimuriella densifolia gen. et sp. nov. is described and restored based on organic connections between axes, sterile foliage (identical to isolated Zamites nipponicus), and ovuliferous Williamsonia-type flowers. Its associated Weltrichia-type microsporangiate flowers strongly warrant conspecificity. The unique combination of a divaricate growth habit and Zamites-type foliage necessitated the erection of the new genus Kimuriella. Detailed nomenclatural comparisons are made with coeval European bennettites, specifically Williamsonia gigas and Williamsonia pecten from the Bajocian of Yorkshire, UK, addressing the limitations and classical circumscriptions of form-classification for isolated fossil organs. Finally, this study discusses the palaeo-ecological interpretations of the coastal or river delta environments where these two bennettitalean species thrived, enhancing our understanding of Upper Jurassic terrestrial ecosystems in East Asia.

A permineralized ovulate cone of Metasequoia Miki (Cupressaceae), representing the oldest record of the genus in Japan, was discovered in the Upper Cretaceous Obisagawa Member of the Ashizawa Formation, Futaba Group (latest Turonian to earliest Coniacian), in Hirono Town, Fukushima, Japan. Here we report its anatomical features and affinities, focusing on the evolutionary history of Metasequoia. The specimen is preserved in a calcareous concretion with numerous plant fragments, including isolated seeds, leaves, and shoots of various affinities. Gross morphology was preliminarily assessed using microfocus X-ray CT, and internal anatomy was studied using serial peel sections, with 3D rendered images. The ovulate cone is nearly cylindrical, ca. 33 mm long and 28 mm wide, and terminates on a sparsely leaved stalk. Fourteen cone scale complexes, arranged decussately on the main axis, bear at least seven ovules, with their micropyles oriented toward the main axis. Along with these cone features, the associated shoots with opposite leaves and the circular winged seeds support its assignment to Metasequoia. Three fossil species are currently accepted in the genus: M. milleri, M. foxii, and M. occidentalis. The new specimen is anatomically distinct from all known species in the genus. Notably, the specimen possesses a uniseriate ring of resin canals internal to the central vascular bundle ring of the cone scale complex. Furthermore, the vascular bundle course within the complex may exhibit characteristics intermediate between Metasequoia and Sequoia. This study provides important insights into the early evolutionary history and morphological diversity of Metasequoia during the Late Cretaceous.

The Bhareli Formation of the West Kameng District, Arunachal Pradesh, India, offers important insights into the early Permian terrestrial ecosystems through the integration of palaeobotanical, charcoal and biomarker evidence. The formation yields plant mega-and microfossil assemblages, alongside bio-geochemical signatures of palaeo-wildfire activity. The megafloral record reflects a typical Glossopteris-dominated Gondwanan vegetation. Palynological analysis allows for a correlation with the Scheuringipollenites barakarensis palynozone of the Damodar Basin, thereby supporting an Artinskian (early Permian) age for the unit. The age of the studied section is also inferred from correlations with known coeval assemblages reported from other Gondwana basins of India. Significantly, the detection of pyrogenic polycyclic aromatic hydrocarbons (PAHs) in samples collected near the Main Boundary Thrust (MBT), where preservation of putative macro-charcoal is extremely poor due to tectonic disturbance, provides evidence for the occurrence of paleo-wildfires. Pyrogenic PAHs such as Pyrene, Fluoranthene, and Benzo(a)anthracene are indicative of biomass combustion, while high molecular weight compounds like Coronene suggest episodes of intense fire. The integration of palaeobotanical data with molecular fire proxies offers a robust multi-proxy framework to reconstruct the palaeovegetation and wildfire regimes of the studied area. The dominance of gymnospermous pollen types, particularly those affiliated with Glossopteridales, as well as the dominance of the genus Glossopteris in the megafossil assemblage, indicates the prevalence of woody, flammable vegetation that likely sustained repeated wildfire activity.

Leaf decay processes are central to understanding plant taphonomy and the formation of fossil leaf compressions. Microbial biofilms and their extracellular polymeric substances (EPS) are increasingly being recognized as key mediators of early decay and preservation. Yet, the influence of leaf biological affinity on biofilm development remains poorly understood. In this experimental study, we investigate exopolysaccharide (EP) production, the principal component of EPS, and microbial community composition on the submerged leaves of three conifer genera—Araucaria, Podocarpus, and Metasequoia—after two weeks of immersion in a natural freshwater pond environment. EP concentrations were quantified at three time points, and associated biofilm microbial communities were characterized using molecular analyses.

Araucaria leaf biofilms produced significantly higher EP concentrations than those associated with Podocarpus and Metasequoia. In addition, distinct microbial taxa were positively correlated with elevated EP production, indicating that the biological affinity of leaves shapes microbial community structure and biofilm development. These results suggest that certain plant taxa, such as Araucaria araucana, may promote the formation of thicker, EPS-rich biofilms that reduce degradation efficiency, stabilize leaf tissues, and create microenvironments favorable for preservation.

Our findings provide experimental evidence that leaf–microbe interactions may directly influence fossilization potential, contribute to taxonomic biases, and possibly promote the preservation of araucarian foliage in the fossil record. More broadly, this study highlights microbial biofilms as active agents in plant taphonomy and suggests that biological controls on EPS production may play an underappreciated role in determining which leaves are preferentially preserved as fossil compressions.

Leaf-wax n-alkane concentrations and average chain lengths (ACL) significantly vary among extant gymnosperm groups. When investigating deep-time archives, further plant groups need to be considered that since went extinct. Also, entirely aquatic plants, as known in the angiosperm clade, are not known to be amongst any fossil or extant gymnosperm group. The Middle to Late Jurassic macroplant assemblage preserved in the volcanic lake deposits of the Haifanggou Formation in Inner Mongolia, China, and attributed to the Yanliao Fossillagerstätte, reflects such a gymnosperm-dominated environment, amongst which the extinct Bennettitales constituted the dominant seed-plant component, with ginkgophytes and cupressoid conifers as additional major components. This fossil environment existed c. 40 million years prior to the rise of the angiosperms. The current study examines the relative n-alkane concentrations preserved in 33 samples from two excavations in the Haifanggou Formation. Despite the high age of the sampled strata, n-alkane preservation is excellent. In addition, the two excavations yield mean ACL25–37 values of 28.2 and 27.8, respectively, and the n-alkane distributions are dominated by n-C27 alkanes and, in some samples, by n-C25 alkanes. Thus, given that Bennettitales were the dominant plant group in the assemblage, we hypothesize that bennettitalean cuticles were composed of n-alkanes with shorter chain lengths than that of extant gymnosperm groups. To test this hypothesis, further verification is required involving the direct analysis of well-preserved fossil bennettitalean cuticles.

Genome size (GS), the amount of DNA in a cell nucleus, varies greatly across land plants, ranging around 2400-fold. Its direct impact on cell size has been linked to key traits such as life strategy, growth habit and rate, habitat preference, geographic range, and diversification rate. Due to genome expansion and contraction mechanisms, GS has varied over time and is hypothesised to have played a significant role in the survival and extinction rates of land plants. Therefore, reconstructing GS variation in fossil plants is essential to better understand its effects on plant evolution and (palaeo)ecology.

Although GS cannot be measured directly in fossil plants, it can be estimated using cell size measurements. Especially its relationship with stomatal guard cell length (GCL) has shown potential as a proxy for palaeo-GS reconstructions. However, further multi-clade analyses are required to improve our understanding of the consistency of the GS–GCL relationship across plant groups.

Here, we thoroughly test the palaeobotanical GS proxy across major plant groups with GCL data from 27 lycophyte species, 97 fern species, 111 gymnosperm species and 658 angiosperm species, assembled from literature and new measurements from herbaria and botanical garden specimens. With a particular focus on non-angiosperm tracheophytes in the newly collected GCL data, we have gathered an extensive GCL dataset that will give more substantial insights into the consistency of the GS–GCL relationship across major plant groups, potentially strengthening the applicability of the palaeobotanical GS proxy and allowing a better understanding of ecological and evolutionary dynamics in land plants.

Emsian fossil assemblages from Laurentia have yielded evidence for anti-herbivore defenses: secretory capitate glands and other glandular emergences (trichomes), spinescent emergences (spines, hereafter) with sclerified cortex and specialized morphology and wound response periderm for piercing-sucking and putative surface feeding wounds. Circumstantial evidence from the Emsian includes epidermis containing secondary metabolites and putative secretory cells in cortical tissues. Together, these demonstrate that by 400 Ma ago land plants had evolved diverse and sophisticated defenses – both mechanical and chemical – against herbivory and mechanisms for healing herbivore-induced wounds. This implies that herbivory had reached significant intensity and ubiquity before the Middle Devonian. In turn, this suggests that plant-animal interactions involving herbivory were initiated and diversified well before 400 myr ago. However, pre-Emsian direct evidence of herbivory is sparse. Rare coprolites with plant material and coeval animal mouthparts cannot be assigned unequivocally to herbivores vs detritivores. Thus, the pre-Emsian evolution of herbivory can only be inferred from indirect evidence. While spines may have served functions other than defense, their occurrence nevertheless provides the best approximation for the intensity of herbivory, in the absence of direct evidence. An exhaustive survey of spines and other putative defenses shows a steady rise of spine-bearing taxa after the Silurian and throughout the Early Devonian, as well as a rise in plants with chemical defenses and with stouter spines, suggesting that the incidence and intensity of herbivory rose quickly starting at the beginning of the Devonian, much earlier than previously thought or implied by direct evidence.

Leaf mining is a specialized feeding strategy in which insect larvae inhabit and feed on the internal tissues of leaves. This strategy not only improves feeding efficiency but also provides natural protection against environmental stressors. For host plants, leaf mining can lead to increased water and nutrient loss and reduced photosynthetic efficiency. In response to these threats, plants have evolved chemical defense strategies to resist herbivory. Fossil leaves with leaf-mining damage provide critical insights into ancient plant-insect interactions; however, the impact of leaf mining on fossil leaf chemistry remains largely unexplored. In this study, attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) was used to analyze the chemical composition of ginkgophyte leaves with leaf mining damage from the Upper Triassic Xujiahe Formation in the Sichuan Basin, Southwest China. Due to the scarcity of insect damage on the leaves of Ginkgo biloba, the leaves of the common ivy (Hedera nepalensis) were selected as a modern reference. Modern results show that mined leaf portions exhibit significant chemical differences from unmined portions, containing higher relative contents of carboxylic acids and polysaccharides, indicating that leaf miners manipulate plant physiology while inducing localized host defenses. In the fossil ginkgophyte leaves, both mined and unmined portions display similar chemical defense-related characteristics, suggesting that leaf mining induced a systemic defense response in this Triassic ginkgophyte. This study provides direct evidence for chemical defense in a Triassic ginkgophyte plant against leaf miners and demonstrates the feasibility of using chemical analysis to unravel plant defense mechanisms in deep time.

A distinctive seed type is present in the stomach of two species of mammal and one unidentified small trogon-like bird from the late early to early middle Eocene oil shale (Cenozoic, Paleogene) of Messel, Germany. The bird contains several more or less intact seeds. Amongst the mammals two species of the rodent Masillamys contain numerous seed coat fragments. As revealed by SEM the surfaces of the seeds and seed fragments have a very distinctive pattern of polygons formed by rounded ridges. Within each polygon there are numerous (>10) small depressions. This pattern is identical to the surface cell pattern of seeds found intact and dispersed in the Messel oil shale named Carpolithus sp. 57 by Collinson, Manchester and Wilde in 2012. Complete seeds are small (3-4mm), globose to ellipsoidal and have very shiny surfaces. The majority of seed specimens in the oil shales are cracked indicating that the seed coat was very brittle. Almost all C. sp. 57 seed specimens in the palaeobotany collections of the Senckenberg Research Institute and Natural History Museum, Frankfurt are single seeds, none are multiple seeds. No fossil fruit has been found containing these seeds. Unfortunately the botanical affinity or growth habit of the plants which produced these seeds has not yet been identified. The seeds have been recorded from multiple collecting subsites at Messel so their parent plant must have been widespread in the vegetation around the Messel lake. Therefore, the seeds would have been a readily available resource for both mammals and birds.

The Gratkorn pit, comprising late Middle Miocene sediments and fossils, is well known for its diverse terrestrial vertebrate fauna. Vertebrate fossils and associated coprolites are found in a paleosol at the base of the pit, which is part of the Gratkorn Fm and is of late Serravallian age (c. 12.2 Ma). The paleosol is overlain by limnic sediments of the Gleisdorf Fm. Until now, paleoecological reconstructions have primarily been based on the vertebrate record of the Gratkorn Fm and the plant record of the Gleisdorf Fm. These datasets are difficult to compare but have suggested changes in temperature and precipitation along the section. So far, only few plant macrofossils and no spores/pollen have been found in the Gratkorn Fm, hindering direct comparison with paleobotanical data from the Gleisdorf Fm. Interestingly, hyena coprolites from the uppermost part of the Gratkorn Fm are rich in fossil spores and pollen, with over 100 taxa identified to date. Preliminary investigation of the spore and pollen content of the coprolites suggests a similarly diverse vegetation during the accumulation of the vertebrate-bearing sediments as in the overlying limnic unit. As a first step, the taxonomy of spores and pollen from the coprolites is being established and compared with that of the overlying Gleisdorf Fm. Based on the plant record, vegetation units surrounding the Gratkorn site during deposition of the paleosol will be reconstructed, and paleoclimate will be estimated based on the ecological preferences of potential modern analogues of the parent plants producing the spores and pollen.

A new diverse acritarch flora has been recovered from siltstones and claystones of the Landeyran Formation from the Early Ordovician Cabrières Biota and coeval Landeyran section in the southern Montagne Noire, France. Never studied since the late 20th century, the current study enriches the knowledge on the acritarchs from the southern Montagne Noire by the identification in this moderately to well-preserved assemblages of biostratigraphical, palaeobiogeographical and palaeoecological signals. In addition to typical Early and Middle Ordovician genera Veryhachium, Striatotheca, Peteinosphaeridium, and Aureotesta, identification of several typical index taxa from the Early Ordovician, such as Coryphidium bohemicum, Ampullula spp., Barakella spp. associated with the absence of Arkonia, Frankea, Orthosphaeridium and Dicrodiacrodium allows a precise assignment of a late middle to early late Floian age (transition Fl2 to Fl3) confirming the biostratigraphic data from trilobites and graptolites biozonations. The attribution of the assemblages to the high southern latitudes of the peri-Gondwana province is expressed by the presence of Arbusculidium, Coryphidium, Striatotheca and Acanthodiacrodium. The current studies suggest a re-evaluation of the local First Appearance Datum of Ampullula in the southern Gondwana from the early Darriwilian to the late Floian. The evolution of the relative proportion of the different groups and genera within the Landeyran section express a progressive change from a galeate’s to a polygonomorphs’ dominated palaeo-assemblages suggesting the presence of a transgressive phase to the Landeyran Formation conform to the sedimentary data.

The Middle Ordovician of the palaeocontinent Baltica provides some of the best preserved and most diverse acritarch assemblages of the lower Palaeozoic. Acritarch research started with the pioneering studies in the 1930s by Alfred Eisenack, who first collected erratics from the southern coast of the Baltic Sea (Eisenack, 1938). Being fully aware of the morphological variability, Eisenack subsequently published further descriptions from erratic boulders (Eisenack, 1958), but also from outcrop material (Eisenack, 1959, 1968), including the Hälludden section of Öland (Eisenack, 1976). A great number of widely used acritarch genera and species have been described from this area since the 1960s (e.g. Staplin et al., 1965; Kjellström, 1972), usually with the main objective to provide biostratigraphically useful key-taxa. Here, we document that progressive changes of key morphological characters, such as the average process length, as well as the relative abundance of different morphotypes, are continuous throughout the sections. The progressive variations, observed from deeper- to shallower-water environments, demonstrate changing proportions of acritarch taxa and a high degree of morphological plasticity among acritarch morphotypes, thereby challenging their use in biostratigraphical correlation. The morphotypes remain useful, however. Here we present evidence that proportions of acritarch morphotypes and selected morphological criteria can be used for ecostratigraphical applications. Over half a century ago, Alfred Eisenack, together with other pioneers, noticed the extremely high variability of the acritarchs, and already noticed at that time that the morphology was related to the palaeoenvironment. Eisenack was right!

The term ‘peteinoid acritarchs’ derives from the genus Peteinosphaeridium Staplin, Jansonius and Stanley 1965 from Öland (Sweden). They are described in the literature as displaying a large morphological variability in their processes. This had been noticed and discussed by Alfred Eisenack since the 1930s, who evoked caution when assigning new species and/or genera. However, several new species and genera were described years after the creation of the genus Peteinosphaeridium leading to an inflation of their diversity and creating difficulties in their classification. Now, besides Peteinosphaeridium, the group contains the genera Asketopalla Loeblich and Tappan 1969, Polyancistrodorus Loeblich and Tappan 1969, Rhopaliophora Tappan and Loeblich 1971, Cycloposphaeridium Uutela and Tynni 1991, and Liliosphaeridium Uutela and Tynni 1991. A literature revision of this group and the assessment of its morphological variability were carried out by bivariate statistics for the literature data, and by multivariate statistics for Öland specimens. Bivariate statistical tests showed that, compared to vesicle diameter, processes length displays more variability among genera. Processes length suggests similarities for Asketopalla–Rhopaliophora and Peteinosphaeridium–Polyancistrodorus. For the multivariate analysis, the PCA and LDA (CVA) revealed three different morphotype groups based on the complexity of process morphology. Multivariate statistical tests suggest that the three genera identified from Öland slides, i.e. Peteinosphaeridium, Liliosphaeridium and Rhopaliophora, are significantly different in terms of process morphology. However, at species rank, this difference becomes difficult to distinguish. Peteinoid acritarchs may have better biostratigraphic applications at the genus rank. Hypotheses such us ‘paleo-provinces’ or endemism of peteinoid acritarch should be re-assessed.

Middle Ordovician (Darriwilian) cryptospore assemblages from Saudi Arabia constitute one the world’s oldest record of earliest land plants, thus providing critical information on early evolution of spore-producing plants. In living cryptogams, the tapetum or tapetal-like tissue that lines the sporangial locule produces sporopollenin which is then deposited exogenously onto the developing spore tetrad. The confirmed presence of a tapetum in liverworts, and new information on spore wall ultrastructure in extant hornworts suggest new ways to assess tapetal activity and sporopollenin deposition in an evolutionary context.

Here, we review what can be inferred about spore development based on lower Paleozoic cryptospore ultrastructure and compare that to what we now know about basal bryophyte sporoderm development. Laminar sporoderm is characteristic of Cambrian and Early Ordovician cryptospores, implying a strictly endogenous source for the sporopollenin. By the late Cambrian, likely endogenous pathways had evolved to produce multiple enclosing spores with the final units as dyads (e.g., Agamachates). A marked change first occurs in Cryptotetras from Darriwilian strata of Saudi Arabia, in which a single basal lamina is found underlying a homogenous spore wall. This implies exogenous addition of sporopollenin to a pre-existing endogenously-produced framework of lamellae, occurring inside of a space separated from the external environment (sporangium). The sporopollenin is produced in cells lining the sporangium; i.e., a tapetum. Thus, the fossil record of spore walls records the serial acquisition of developmental pathways over millions of years from various sources that culminated in a canalized scheme seen today in their descendants, the embryophytes.

Nematoclasts are smooth-walled and banded organic tubes of nematophytes origin found as dispersed elements in Silurian non-marine deposits. Recent molecular compositional analyses from the Rhynie Chert by Loron et al. indicate Prototaxites taiti to be distinct from fungi, eroding support for fungal affinity of nematoclasts at large. We analyzed a set of Nematothallus lobata specimens of Wenlock (Silurian) age for their $^{13}$C content, which yielded a mean $\delta$$^{13}$C value of -27.92 ± 0.74 -- consistent with derivation from C3 (Calvin cycle) land plant photosynthesis. We speculate that N. lobata may have been the protonemal phase in an early thalloid plant life cycle, which formed resistant-walled caulonemal filaments. A survey of Silurian nematoclasts from the central Appalachians shows an evolutionary increase in wall complexity and variety. This provides a developmental (morphological) model for the origin of both smooth and banded nematoclasts. Protonemal thalli were directly exposed to UV-B during life, so it is possible that phenylpropanoid pathways in protonemal cells were under selective pressure to provide UV-B absorption, stimulating the primordial synthesis of lignin.

We hypothesize that the acquisition of the underlying developmental (genomic) basis for caulonemal walls was retained and later repurposed into walls of “proto-tracheary elements” derived from the primitive shoot apical meristem (SAM) in early embryophytes. The ability to grow an organic tube, deposit secondary wall thickenings, and synthesize lignin may have become part of the ancestral embryophyte toolkit during the early Silurian just prior to incorporation into the full genetic repertoire of the land plant embryo.

Vitrinite Reflectance (VRo) determination is the standard method used to estimate the thermal maturity of sedimentary basins but vitrinite (derived from ‘woody’ plant tissues) is absent in pre-Devonian rocks. Acritarch Palynomorph Darkness Index (PDI) can be used as a proxy for VRo in pre-Devonian marine strata. In principle, miospore (trilete spore) PDI can be used as a proxy for VRo in pre-Devonian nonmarine strata but the stratigraphic record of miospores only extends back into the latest Ordovician and they are often too rare in latest Ordovician-Silurian samples for this technique to be applied successfully. Cryptospores are common in pre-Devonian strata with a record extending back to the Mid Ordovician. These palynomorphs were produced by eophytes and their walls have a similar chemical composition to those of trilete spores. We tested the equivalence of cryptospore and trilete spore PDI by calculating PDI on co-occurring specimens from the same Late Ordovician to Early Devonian samples. PDIs of Miospores (trilete spores) and Cryptospores (hilate monads, permanent dyads and permanent tetrads) have been determined in latest Ordovician-Early Devonian samples from China, Saudi Arabia and the UK, where specimens of these palynomorph groups co-occur in samples of varying levels of thermal maturity. Elucidation of the correlation of Cryptospore PDI to Miospore PDI enables the former to be used to estimate the thermal maturity of nonmarine or nearshore marine sequences within the Late Ordovician-Silurian of Saudi Arabia. These include sequences of the Qalibah Formation (Qusaiba and Sharawra members) and the Tawil Formation.

The origin of angiosperms is related to a singular evolutionary event, the origin of the carpel. To understand the origin of angiosperms may require novel approaches to how we think about the problem. The origin of the angiosperms may be considered as a series of existentially related events through the Mesozoic, beginning in the Triassic and culminating in a suite of angiosperm characters which contributed to their rapid diversification in the Lower / Upper Cretaceous. Genidentity (sensu Kurt Lewin 1922) events are diachronic, series of events that are causally connected and represent the same, continuously existing thing, even if that thing changes its properties through time. Using this concept, we discuss the evolutionary importance of morphological innovations related to male-male competition, mate choice and pollinator efficiency. We hypothesize there are six major events beginning in the Triassic and culminating in the Lower Cretaceous that define the origin of angiosperms using the concept of genidentity. The innovations include 1) the tectate-columellate reticulate exine structure (Triassic), 2) the origin of flies (Upper Triassic -Lower Jurassic), 3) the origin of the conduplicate carpel (stigma) (Upper Jurassic – Lower Cretaceous), 4) the origin of the Hymenoptera (specifically Apoidea) (Early Cretaceous), 5) the origin of the symmetrical positioned multi-aperturate pollen (Lower Cretaceous) and 6) the origin of the style as a transmitting tissue, (Upper Lower Cretaceous). We hypothesize that this series of related events all converged in the Lower Cretaceous and taken as a whole define the origin of angiosperms, not any one singular event.

Information on the order in which pleisiomorphic angiosperm characters arose may be helpful in identifying the most likely close stem-relatives or ancestors of angiosperms from the fossil record. We have developed a method to determine the sequence of acquisition of angiosperm-specific traits by exploiting gene and genome duplication events as temporal reference points. As a test case, we have analysed the evolution of the YABBY transcription factor family. Our data suggest a model in which two ancestral YABBY genes were present in the most recent common ancestor of living seed plants, one of which was expressed specifically in reproductive tissues. This gene appears to have been lost from a common ancestor of living gymnosperms, but underwent successive duplications along the angiosperm stem lineage to generate three gene lineages that promote the development of distinct sets of reproductive organs. From these data, we postulate that the hypothesized reproductively expressed YABBY gene promoted the expansion of an ovulate cupule in early seed plants, and that this structure became the outer integument of the ovule in angiosperms. This hypothesis is consistent with the proposition of cupulate gymnosperms such as Caytoniales as close stem-relatives or ancestors of angiosperms.

The lower Aptian flora of the Crato Fossil Lagerstätte in the Araripe Basin in NE Brazil opens a unique window to a late Mesozoic low latitude paleo-ecosystem in northern Gondwana. The investigation of the floristic composition of the Crato Formation flora and the combined analysis of its floristic composition and geological background data provide an important opportunity to explore the environmental and climatic conditions under which gymnosperms were still the predominant group of vascular plants in the paleovegetation while flowering plants were already diversified. Gymnospermous plants were identified from foliage, reproductive structures, wood and pollen records. Some whole-plant species could be reconstructed so far but a considerable number of fossils belongs to incompletely known plants. Generally, gnetalean plants have had the highest diversity in Earth’s history during the Early Cretaceous, which is also supported by the phytotaphocoenosis of the Crato Formation flora. Besides members and relatives of extant families and genera of Gnetales several extinct taxa with gnetalean affinity were described. The conifers include representatives of Araucariaceae, Cupressaceae, Pinaceae, Podocarpaceae and the extinct Cheirolepidiaceae and „Podozamitaceae“. Other extinct gymnosperm orders such as Caytoniales and Erdtmanithecales were present as well. Not all taxonomic groups recognized from the pollen assemblage were also evidenced in the macrofossil component so far, and vice versa. The habit of gymnospermous plants was considered large trees (araucarias), shrubs (likely frenelopsids; gnetaleans), and herbaceous plants (gnetalean-like taxa). Their morphological and anatomical characteristics indicate various adaptations to specific environmental and climatic conditions.

Discoveries of new fossil taxa, improved data on known fossils, and reinterpretations of the morphology of key taxa have challenged previous hypotheses on seed plant phylogeny and the origin of angiosperms. To test the impact of these developments, we amassed a data set with 10 new taxa, including Doyleales (Cretaceous, some originally assigned to the Triassic "seed fern" order Corystospermales), two Mesozoic conifer taxa with multiveined leaves, the cupulate "seed ferns" Petriellaea (Triassic) and Ktalenia (Cretaceous), and the Cretaceous compound strobilus Protoephedrites, plus several new and redefined characters. We rescored ovulate structures of glossopterids as cladodes with ovules on the side facing a subtending leaf, ovules of Bennettitales as lacking a cupule and borne on simple megasporophylls, and cones of Doyleales as compound strobili with bracts and lobed cone scales (fertile short shoots). We analyzed the data with both parsimony and Bayesian methods, with and without molecular constraint trees.
All our analyses associate Doyleales with conifers with multiveined leaves, Protoephedrites with extant Gnetales, and Ktalenia, Petriellaea, and Caytonia with angiosperms. The positions of glossopterids, Pentoxylon, and Bennettitales vary in parsimony analyses, but in Bayesian analyses Pentoxylon is linked with glossopterids and Bennettitales with gnetophytes. These results may favor origin of the angiosperm leaf by webbing of a pinnately compound leaf, rather than differentiation of vein orders in a taeniopterid or glossopterid leaf, and derivation of the carpel from a megasporophyll with pinnately borne cupules (homologous with bitegmic ovules), rather than a leaf plus an axillary cupule-bearing branch.

The Las Hoyas fossil site (Cuenca, Spain), is a Barremian (129 Ma) Konservat-Lagerstätte renowned for its exceptional preservation. This study analyzes its plant community through the fossil associations of taxa present at different spatial and temporal scales: rock layers (containing fossils deposited within a short time window), excavation areas (containing fossils produced in the same location over a longer period of time), and lithosomes of the site (representing a longer time span and a broader area). The study is based on 13,608 plant fossil remains recovered from 20 excavation trenches between 1996 and 2021.

Gymnosperms constitute the most represented group (24.4%), with Frenelopsis ugnaensis being the most common taxon, followed by angiosperms (13.4%), with Montsechia vidalii as the second most abundant fossil remain, and ferns (10.4%). The analysis reveals cyclical patterns in the abundances of taxa such as Weichelia reticulata and Frenelopsis ugnaensis, likely related to environmental changes, recurrent wildfires, and transport into the wetland.

The wetland vegetation is interpreted as comprising four major plant communities: (1) aquatic vegetation, dominated by Montsechia vidalii and accompanied by charophytes; (2) vegetation of ponds margins and watercourses, including bryophytes and the fern Coniopteris laciniata; (3) vegetation of the emergent wetland and floodplain environments, represented by Frenelopsis ugnaensis; and (4) vegetation of savanna-like habitats located farther from the wetland, represented by Weichelia reticulata, and diverse conifers. Compared with previous interpretations, which recognized only three plant communities, this study proposes an additional community by distinguishing more hygrophilous, water-dependent vegetation from more xerophytic vegetation.

The Aptian–Albian interval of the Early Cretaceous (121.4–100.5 Ma) was a pivotal phase in land plant evolution, marked by rapid angiosperm diversification, major vegetation restructuring, greenhouse climate conditions, elevated global temperatures, and repeated oceanic anoxic events.

The Une flora, a recently discovered compression flora from the Une Formation in Colombia, preserves evidence of an Aptian-Cenomanian low-latitude assemblage. Nearly complete leaves, leaf fragments, seeds, fruits and flowers are preserved in siltstone lenses of deltaic sandstone deposits, and were extracted through bulk maceration. This assemblage preserves diverse gymnosperms including Araucariaceae, Cupressaceae, Podocarpaceae, Cycadales, Ginkgoales, Bennettitales, and Gnetales, as well as monocot and non-monocot angiosperms and early flowers with in situ stamens and pollen grains. Lycopodiopsida are also present. Abundant epiphyllous fungi, including mycelia, sporomata, and spores, occur throughout the assemblage.

The Podocarpaceae foliage represents the first Aptian–Cenomanian record for the family from northwestern Gondwana, supporting a long-standing tropical distribution. The flora also suggests humid climatic conditions, consistent with palynological evidence.
The abundant, well-preserved fossil leaves of the Une flora provide a framework for future atmospheric CO2 reconstruction during the Aptian–Cenomanian greenhouse interval using the Franks gas-exchange model. We also plan to infer relative genome size in both angiosperms and gymnosperms based on guard cell dimensions. Initial genome-size results show variation in guard cell length among morphotypes, potentially reflecting differences in ploidy level or repetitive DNA content. Our multi-proxy approach to the Une flora aims to further illuminate tropical Gondwanan plant diversity, ecosystem structure, paleoclimate, and Cretaceous plant biogeography.

I am a retired plant scientist with a strong personal interest in paleobotany and the evolution of plants. I want to contribute to the understanding of how ancient plants lived by using digital media and oil paintings to set life restorations of fossil taxa within realistic interpretations of deep time landscapes. My artwork is deliberately designed to be attractive to the non-specialist and encourage a greater interest in the evolution and importance of plants.

Illustrations of ancient environments normally focus on the fauna and when plants are represented then it is typically the odd cycad or a giant clubmoss. I try to produce more ‘realistic’ interpretations of the plants set within ancient landscapes. I work with paleobotany colleagues in the UK and elsewhere to select the best and most recent life restorations of fossil plant taxa. I then set these restorations within landscapes based, where appropriate, on our understanding of modern ecosystems. My paleoart makes use of both digital and traditional media, including digital print and cut technology, modelling in clay and 3D computer modelling and printing. I then bring the individual plants together in landscapes using digital drawing, photographic composites and large- scale oil paintings.

The depiction of plants in palaeoart is key to communicating to diverse audiences about life in the deep past. Palaeoart today tends to focus on animals, particularly on tetrapods, and this can be seen as part of the broader issue of zoochauvinism within science communication and popular culture more generally. However, it is within the field of palaeozoological art that much thoughtful work has been undertaken to identify best practices, and to systematise the process of creating such art from fossil evidence. Principles such as phylogenetic bracketing provide artists with a framework for making objective decisions about how to present anatomy for which fossil evidence is absent. This is an evidence-based speculative approach. And while the process of reconstructing and depicting a vertebrate's anatomy - from skeleton, to soft tissues, to integument - is fundamentally different from how plants should be reconstructed, there are pipelines that could be applied to palaeobotanical art, both at the level of whole-plant conceptualisations and for landscape palaeoart. The development of similar shared principles for palaeobotanical art would allow artists greater licence to speculate, and to produce creative, thought-provoking, and exciting artworks with confidence. Accuracy in palaeobotanical art is important, but moving towards a model where the plants depicted are biologically tenable but not limited to the safe, well-rehearsed and repeated reconstructions derived directly from illustrations in scientific papers could reinvigorate popular interest in plants from deep time.

Plant paleoart often turns fossil plants into scenery, although extinct plants can be visually and conceptually as unfamiliar as any animal. Tempskya, a Cretaceous fern known mainly from silicified false trunks, is a striking example: its body was composed of numerous dichotomising axes, petioles and a dense mantle of adventitious roots, yet widely reproduced reconstructions still follow models developed more than 75 to 100 years ago. This contribution presents a revised reconstruction of Tempskya as a case study in scientifically grounded plant paleoart.

The reconstruction combines observations from old and newly examined specimens with biomechanical comparisons to extant rhizomatous ferns such as Davallia and Phlebodium. It visualises the plant not as a conventional tree fern, but as a modular, root-supported, partly self-renewing organism with foliage probably concentrated in the upper crown and an outward-thinning root mantle. Special attention is given to decisions that must be made when translating incomplete fossil evidence into an image: frond size, trunk outline, living versus decayed tissues, habitat, and the degree of visual uncertainty.
By making these assumptions explicit, the reconstruction treats paleoart as a transparent scientific hypothesis rather than a final picture. Tempskya thus becomes a central character in Cretaceous wetland ecosystems and illustrates how plant paleoart can communicate morphology, ecology and uncertainty to both scientific and public audiences.

Plant palaeoart sits at an innovative threshold between scientific description and artistic revelation; its promise lies not in passive illustration but in dynamic knowledge production and access. Drawing on ongoing research with Queensland Museum's palaeobotanic type collection, I present an intra-disciplinary methodology in which artistic practice and palaeobotany operate as mutually generative epistemic partners rather than as discrete domains of explanation and depiction. The research engages Cenozoic silicified and permineralised holotypes such as Spondylostrobus rozefeldsii, Fontainocarpa foraminata and Capella raulingsii through a suite of imaging and making practices: synchrotron X‑ray micro‑CT at the Imaging and Medical Beamline (Australian Synchrotron); complementary neutron tomography at the DINGO beamline (ANSTO, Lucas Heights); focus‑stacked macro photography; photogrammetric three‑dimensional reconstruction; 3D printing; laser etching; artists' books; and wearable sculpture. Read through Karen Barad's diffractive methodology and Heidegger's aletheia, these techniques non‑destructively revealed internal morphologies and diagnostic taxonomic features in specimens that had resisted classification, while simultaneously yielding works of art that re‑present deep time to specialist and non‑specialist audiences. The exhibitions Aletheia and Deep Time demonstrated how palaeoart can 'democratise the collection', returning rarely viewed holotypes to scientific, artistic and public circulation and seeding peer-reviewed palaeobotanical and artistic publications. I reflect on perspectives from both sides of the art–science threshold: collaborative knowledge creation and democratic access. I propose a three-fold promise for plant palaeoart: a research instrument visualising inaccessible morphology; a critical practice innovating palaeobotanical visual practice; and a public-facing form communicating evolution and extinction with affective force that text alone struggles to achieve.

Exposed Devonian rocks are known only from northwest Saudi Arabia, adjacent to the Precambrian Arabian Shield. Most of the Devonian deposits, which comprises the upper Tawil, Jauf and most of the Jubah formations, occur in subsurface, both in the northwest but also in eastern Saudi Arabia. Some exploration wells have penetrated up to 2,300 ft of Devonian section throughout eastern Saudi Arabia and more than 5,000 ft in the centre of the Nafud Basin. Although the Devonian is seemingly conformable with the overlying Mississippian section, its upper boundary is often eroded by either the pre-Khuff (Mid Permian) or pre-Unavzah (Permo-Carboniferous) unconformities in eastern Saudi Arabia. The Saudi Arabian Devonian succession was generally deposited in a continental to shallow marine depositional system in which substantial siliciclastic-dominated deposits accumulated, in essentially broad transgressive-regressive cycles. A retrogradational cycle (fining-upward) encompassing the Early Devonian Tawil and Jauf formations, followed by a progradational cycle (coarsening-upward) through much of the Mid-Late Devonian Jubah Formation. The terrestrially dominated paleoenvironments of the upper Tawil, Jauf and Jubah formations provide a record of the rapid evolution of Devonian land plants in the form of their dispersed miospores. Thus, these palynomorphs are the chief biostratigraphic tool to age date and correlate these deposits. Acritarchs and chitinozoans are often absent or generally less abundant, although they occur in some specific levels. The current operational palynozonation is robust with nine palynozones combined with numerous palynological events.

Eleven sedimentary rock samples of the upper 15 m of the Rio da Batateira Formation from the Cascata section (sensu Heimhofer and Hochuli, 2010) have been investigated investigated using routine application of SEM on pollen. The sampled section comprises fluvial to deltaic sedimentary rocks of Aptian age. Up to now, 22 eudicot pollen could have been identified, such as Trisectoris reticulatus together with numerous small-sized and large-sized Tricolpopollenites- and Retitrescolpites types. Particularly, when the pollen grains are small (<20 µm), the application of SEM facilitates the differentiation of pollen ektexines of pollen that looks similar (e.g., “scabrate”, “reticulate”) when using solely LM. High magnification of SEM demonstrates that ektexines can be striate, striato-reticulate, rugulate, coarsely to finely reticulate, homobrochate, heterobrochate, having brochi with or without free standing columellae, muri with long or short columellae, tectate foveolate or perforate, or semitectate with supratectal ornamentation or without ornamentation, thus displaying a high variety of pollen wall sculpture and ornamentation. The results of the high resolution SEM investigation of the Rio da Batateira sedimentary rocks show that the NW Brazil was one of the localities that witnessed an early diversification phase of angiosperms in the northern Gondwana realm.

The composition of palynofloras from 41 samples from the ?late Aptian– Cenomanian Wasia Formation in the Arabian Gulf, offshore Saudi Arabia, revealed diverse dinocysts, spores, and gymnosperm and angiosperm pollen.

Angiosperms are comprising up to 25% of the palynoflora and exhibit a great range of morphological types. This remarkable diversity is reflected by more than 50 identified taxa. The most frequent forms included monocolpate Transitoripollis cf. anulisulcatus, Echimonocolpites tersus, Pennipollis sp. A, polyporate Penetetrapites mollis and the questionably angiospermous Afropollis aff. jardinus. The triaperturate pollen grains are remarkably diverse, including Tricolpites cf. parvus, Rousea georgensis, ?Retitrescolpites sp. A, and Striatopollis sp. A. Rare forms included the tetracolpate Quadricolpites reticulatus, monocolpate Similipollis sp., Dictyozonia sp., trichotomosulcates Doyleipollenites sp., syntricolpate Trisectoris reticulatus, winteraceous pollen tetrads Qatanipollis valentini, triaperturate Rousea doylei, R. brenneri, and Phimopollenites augathallaensis. The assemblage includes newly described taxa.

Considering the broader geological context, it is intriguing to explore the role of sea-level fluctuations in driving angiosperm speciation. Boukhamsin et al. (2023) suggests that these fluctuations might have played a crucial role in facilitating both aquatic and terrestrial angiosperm diversification. It is plausible, therefore, to hypothesize that the observed moderate increase in diversity during the late early Albian phase could be influenced by the sea-level drop associated with KAl3 of Haq (2014).

The South Asian Kachin amber deposit from northern Myanmar is renowned for its remarkable fossil preservation, providing unprecedented insights into the early evolution and diversification of angiosperms. We investigated mid-Cretaceous flowers with remarkable stellate trichomes preserved in this amber by combining synchrotron X-ray scans of previously undescribed specimens and datasets from previous studies. We re-examined and reassessed the morphology and affinities of several described fossils, including the angiosperm flowers Antiquifloris Poinar and R. Buckley and Eophylica Shi, Wang et Engel (Rhamnaceae), but also the supposed green alga Electrophycus Poinar & Brown. The high-resolution scans enabled three-dimensional visualization of floral structures and revealed morphological details that had not been previously documented. Our analyses shows that all examined taxa share similar internal and external characters that do not correspond to any known extant or extinct angiosperm family, including as the previously suggested Rhamnaceae. Phylogenetic analyses using broad-scale angiosperm datasets suggest that these fossil flowers are affiliated with early-diverging angiosperm lineages related to Austrobaileyales or Chloranthaceae. Our findings are not only more consistent with other Early- to mid-Cretaceous angiosperm floras, but also align more closely with previous paleoenvironmental reconstructions of the Kachin amber forest.

Late Cretaceous floras from Central Europe provide crucial insights into early platanoid evolution. This study analyses material recovered from the Cenomanian of the Bohemian Cretaceous Basin and the Coniacian–Santonian of the South Bohemian Basins.
In the Czech Cenomanian, Platanaceae are represented by two types of staminate inflorescences borne on a common axis, varying in arrangement and size. Platananthus sp. displays small globular inflorescences consisting of male flowers with five stamens, featuring well-developed connectives, and five tepals. In contrast, large globular inflorescences associated with Ettingshausenia bohemica foliage consist presumably of four stamens, indicating a potentially tetramerous structure. Cenomanian foliage also includes E. laevis and E. cuneifolia. Within the Coniacian–Santonian of the South Bohemian Basins, the family is represented by the highly heterophyllous species Ettinghausenia senonensis and newly recovered staminate inflorescences reported in this study.

The new species of Quadriplatanus comes from the vicinity of České Budějovice, from the Klikov Formation (Coniacian–Santonian). The formation consists of fluvio-lacustrine infills of claystone and sandstone. Sediment abundant in plant material was bulk-macerated and sieved for mesofossils. The material shows globular inflorescences borne on a common axis. Each flower shows four tepals and four stamens with small connectives, bearing in situ prolate to spherical tricolporate pollen grains with a reticulate exine. All the Late Cretaceous platanoids are reconstructed as growing on alluvial plains of Cretaceous rivers, a habitat that mirrors the environment of extant Platanus species.

The monocot family Hydrocharitaceae is morphologically characterised by a strong adaptation to aquatic habitats. Members of the family show the greatest variability among aquatic angiosperm families comprising both freshwater and marine species.
We describe fossil fruits from the Turonian-Santonian of the South Bohemian Cretaceous Basin in Czechia. Bonaquella is characterised by radially digitated fruits consisting of a single, unilocular carpel, with an anatropous ovule with basal placentation. The fruit is flat, ovate and indehiscent, covered by papillae in central part and fringed by large multicellular, branched emergences laterally. Its style is straight, unbranched, and occasionally shows an annular swelling in its basal part. The single seed is broadly ovate with the hilum next to the micropyle. The seed coat consists of a thin and smooth testa and a tegmen consisting of quadrangular cells covered by delicate micro-tubercles; in the micropylar area cells decrease in size having anticlinal cell walls thickly cutinised.
Bonaquella shares a number of characters with Hydrocharitaceae, including indehiscent fruits, the presence of well-developed style, and having a micropyle developed from its inner integument. Its tegmen shows similar cells covered by delicate micro-tubercles. Anatropous ovules are found in the family, they are known e.g., from Stratiotes and Najas. The most important character of Bonaquella is the presence of micro-tubercles on the tegmen. This character is synapomorphic for all members of the Hydrocharitaceae.

The early diversification of angiosperms has been documented by diverse Cretaceous fossil flowers, most of which are preserved as three-dimensional charcoalifications. Here, we describe Bohemiantha tricarpellata gen. et sp. nov., a new charcoalified flower from the Late Cretaceous of southern Bohemia, Czech Republic. We documented internal and external floral morphology of several specimens using scanning electron microscopy (SEM) and high-resolution X-ray computed tomography (HRXCT). The phylogenetic placement was evaluated through a two-step approach, first using an angiosperm-wide dataset followed by an analysis within the order Ericales. Bohemiantha tricarpellata exhibits a pentamerous perianth differentiated into calyx and corolla. The calyx is actinomorphic, with five free sepals arranged in a single whorl with quincuncial aestivation. The corolla is only partially preserved, but petals are apparently united at least at the very base. The gynoecium consists of three united carpels and is further characterized by a mostly superior ovary with a raised nectariferous ring, a robust style, and three short commissural stigma lobes. Numerous anatropous ovules are inserted on axile placentae. The androecium is unknown. Dispersed pollen grains are prolate and triaperturate. Detailed morphological comparison with extant taxa, along with explicit phylogenetic analyses, strongly support the placement of B. tricarpellata within the asterid order Ericales. We found strongest support for a potential relationship with Fouquieriaceae and Clethraceae, respectively. However, support values are generally weak and relationships with other ericalean lineages such as Diapensiaceae and Marcgraviaceae are possible.

The Suriname coastline, as part of the Guianas is characterized by westward migrating mudflats formed by Amazon River sediments. In this study we did palaeoenvironmental and vegetation analysis of the Suriname coast. We analysed samples from the nearshore Powisi-01 well and determined the palynological and geochemical composition of these sediments. Two main palynological zones and six subzones were identified. The lower zone consists of palynomorphs of Late Paleocene to earliest Eocene age occur, including palms and other angiosperms. The Paleocene-Eocene Thermal Maximum (PETM), is also detected in this section part. A barren section follows, that is overlain by Early Miocene, and Middle/Late Miocene to Pleistocene sediments. Palynological diversity is high throughout the well section, and pointing at a tropical lowland flora in the hinterland. Geochemical compositions further indicate that sediments are mainly of cratonic provenance, with the top at c. 200 mbsl of the section presenting a mixed sediment signal of Andean/Amazon, Orinoco, and Amazon craton-derived sediments. Regional studies indicate that Andean sediments likely reached the Guiana coastline during the Late Miocene, but more research is required to determine exactly when the Amazon River began influencing the Guianas coastline.

Keywords: Upper Cretaceous, Tremp Formation, Allueva Formation, Iberian Peninsula, Paleoecology

The Campanian–Maastrichtian interval was a period of significant climatic and environmental changes that profoundly affected flora and fauna worldwide. In the NE of the Iberian Peninsula, this interval is represented at several localities documenting a faunal turnover during the Maastrichtian, though palynological studies remain scarce. In the Maestrazgo domain (Iberian Chain), newly discovered fossil-bearing sites within the middle–late Campanian Allueva Formation represent a continental succession yielding macro- and microbotanical remains alongside a vertebrate fauna dominated by titanosaur sauropods, offering a promising window into Campanian palaeovegetation of Iberia.

The Maastrichtian Tremp Formation (South-Central Pyrenees), one of the few continental records close to the Cretaceous–Paleogene boundary in Europe with solid chronostratigraphical control, has been palynologically studied at three upper Maastrichtian sites (C29r magnetochron). Palynological assemblages are dominated in abundance by Normapolles angiosperms, reflecting regional arboreal communities of Fagales, but show notable differences between localities: older sites reveal Gondwanan influence (Bacumorphomonocolpites), while the younger one shows boreal influence (Aquilapollenites, Sciadopityspollenites), along with greater gymnosperm pollen abundance. These floristic shifts, observed across two distinct palaeoenvironments (a lagoonal transitional system and an alluvial floodplain), may reflect the Latest Maastrichtian Warming Event and subsequent cooling, illustrating the capacity of Iberian plant communities to respond to short-term climatic stress near the end of the Cretaceous.

Funding/Acknowledgements: This work was supported by MICIU/AEI/10.13039/501100011033/ERDF, EU (projects PID2023-148083NB-I00 and PID2024-158833OB-I00), Aragon Regional Government (Group E18_23R Aragosaurus), and Xunta de Galicia (Group GRC-ED431C 2025/52).

Antarctica was home to extensive forest ecosystems during the Late Cretaceous. While a rich diversity of vascular plants have been identified from Upper Cretaceous deposits in West Antarctica, only a handful of bryophyte families have been reported. Here we provide a preliminary report of a rich permineralized bryoflora from the Campanian Sitio Feliz and Baculites Hill localities on James Ross Island, Antarctica. Importantly, the mode of preservation of plants from these localities allows us to observe important anatomical details and microbial associations. Fossil bryophytes from these localities are primarily mosses and are found in calcium carbonate concretions as isolated gametophytes or in dense concentrations comprising dozens of individual gametophytes. Bryophyte concentrations are roughly 5×5 cm and superficially resemble moss mats that are of a size, frequency, and diversity not yet documented in the fossil record. There are over a dozen novel moss and liverwort morphotypes in these concentrations. Preliminary taxonomic analysis suggests that some of these morphotypes belong to Grimmiaceae and Dicranaceae. Isolated gametophytes expand the taxonomic diversity of this fossil bryophyte flora and include Rhabdoweisiaceae. Several isolated gametophytes have well-preserved gametangia. Furthermore, several mosses have epiphytic microbes on leaf surfaces. While palynological studies of Upper Cretaceous deposits in West Antarctica typically only reveal a few bryophyte clades (e.g., Sphagnaceae, Ricciaceae, and Sphaerocarpales), the permineralized flora from the Sitio Feliz and Baculites Hill localities strongly indicates that mosses were diverse elements of the Late Cretaceous polar forests of Antarctica.

The enigmatic fossil-genus Lesleya Lesquereux classified either to early cycads or to pteridosperms is considered as an “upland”, “extrabasinal”, dry-tolerant plant. New excavation in the Vaulnaveys-le-Bas (French Alps) revealed about 60 specimens of the Westphalinan D (late Moscovian) age. Unfortunately, scleritization state of preservation cause that incomplete specimens are without epidermal structures preserved. Otherwise, some lanceolate leaves have obtuse apices and simple, slightly S-shaped venation preserved. The complete leaves might be up to 250 mm long. Similar leaf dimensions and venation occur in nineteen specimens from boreholes in different basins in the Bohemian Massif including the Lubná near Rakovník locality (the Bolsovian, early Moscovian), from where the most specimens also with acute bases and cuticles have been studied. The leaves are amphistomatic with haplocheilic, anomocytic stomata. So, the data are sufficient for erection of a new species Lesleya belledonnensis sp. nov. The specimens from French Alps show to allochthonous origin. In Lubná near Rakovník, two specimens have been found in tuff above coal seam among autochthonous plants, whereas most specimens are fragmentary and come from laminated tuffite above the tuff. This assemblage contains many allochthonous, draw-tolerant species like: Dicranophyllum, Discinites, Rhacopteris, Palaeopteridium and some endemic medullosan pteridosperms. Lesleya in French Alps is accompanied by a dominance in the taphocenosis of dry-tolerant plants as Cordaites in their giant forms and Dicranophyllum. The research was subsidised by a project GACR 25-16958S.

The lower Permian of the Southern Alps (N Italy) represents one of the largest and best-preserved volcanic successions of the upper Cisuralian in Europe, including the Athesian Volcanic District (AVD), the Collio Basin, and the Orobic Alps. The AVD, in particular, provides an exceptionally high-resolution chronostratigraphic framework supported by detailed geological mapping and U–Pb zircon geochronology. Continental sedimentary sequences intercalated within volcanic units were deposited during phases of reduced volcanism, mainly in alluvial–lacustrine environments and yield abundant and diverse paleobotanical remains. Palynological assemblages from ten stratigraphic sections belonging to the Monte Luco, Verano, Guncina, and Tregiovo formations have been studied, spanning a middle to upper Kungurian age interval. Two palynozones were differentiated: the Vittatina and Protohaploxypinus palynozones. Comparative analysis of these assemblages allows refinement of the stratigraphic ranges of several key Permian palynological taxa. New AVD records of these taxa, traditionally considered typical of younger intervals (Guadalupian to Lopingian), have implications for their chronostratigraphical ranges, at least within the southeastern Euramerican phytoprovince. On the other hand, preliminary paleoecological results further suggest changes in palynofloral composition potentially linked to volcanically driven environmental perturbations. These results highlight the value of the AVD as a radiometrically calibrated reference for Cisuralian continental palynostratigraphy, providing a framework for future interbasinal correlations across the Southern Alps. Moreover, the paleoecological analysis emphasizes the relevance of these associations for understanding the effects of volcanic environmental stress over deep time floras.

Accurate pollen identification is fundamental to palaeoecological reconstruction, yet traditional morphology-based approaches often struggle to distinguish closely related taxa. In recent years, spectroscopic techniques such as Fourier-transform infrared (FTIR) and Raman spectroscopy have provided new insights into pollen wall chemistry and improved taxonomic resolution. Fluorescence Lifetime Imaging Microscopy (FLIM) offers an alternative approach by detecting fluorescence lifetime signatures associated with sporopollenin composition.

To evaluate the potential of FLIM in palynology, we investigated pollen from six species of the mangrove genus Sonneratia, an ecologically important taxon with a rich fossil record. Fluorescence lifetime data were obtained from pollen walls and analysed using multivariate statistics. The results demonstrate that FLIM effectively differentiates the six species into four major groups, with the long-lifetime component (τ₃) representing the principal variable responsible for species separation. Hybrid taxa occupy intermediate positions in fluorescence lifetime space, showing broad correspondence with previously proposed phylogenetic relationships. Furthermore, the introduced species Sonneratia apetala exhibits a distinct fluorescence lifetime signature compared with native Chinese species, suggesting differences in pollen wall chemistry related to evolutionary history and ecological adaptation.

Our results indicate that fluorescence lifetime signatures preserve taxonomic, phylogenetic, and ecological information that complements traditional morphology and other spectroscopic methods. By establishing reference datasets from modern taxa, FLIM provides a promising framework for comparing extant and fossil pollen. Future integration of FLIM with FTIR, Raman spectroscopy, and machine-learning approaches may significantly improve species-level pollen identification and enhance palaeoecological reconstructions of mangrove ecosystems and other vegetation types.

Single-grain pollen analysis holds significant promise for advancing chemical palynology, enabling the potential future classification of morphologically similar taxa based on taxon-specific sporopollenin chemistry. Fourier-Transform Infrared (FT-IR) spectroscopy and microspectroscopy (µFT-IR) are widely used to differentiate morphologically similar grains but face limitations from Mie scattering and coarse spatial resolution. Here, we present the first application of Optical-PhotoThermal Infrared (O-PTIR) spectroscopy to chemically treated single pollen grains, using Molinia caerulea as a model taxon to fully evaluate the technical capabilities and limitations of this technique. O-PTIR achieves sub-micron "super-resolution" infrared spectroscopy through non-contact, non-destructive measurements by exploiting the photothermal effect. O-PTIR spectra exhibited close similarity to FT-IR datasets, with all major sporopollenin bands present and only minor peak shifts (~ 4 cm⁻¹). Reliable application of sub-micron spectra for classification purposes requires a robust understanding of intra- and inter-grain variability. This can now be assessed using O-PTIR to distinguish whether intra-grain surface heterogeneity or true inter-grain biochemical differences drives grain separation. Multivariate analysis of intra- and inter-grain variability indicated that greater intra-grain variability does not drive greater inter-grain variability, confirming that observed grain separation reflects genuine biochemical differences rather than technical or surface-related artefacts. Similarly, intra- and inter-grain variability did not differ significantly between plants. While a single O-PTIR measurement can produce a spectrum closely resembling the species centroid, averaging three to four measurements per grain yields reliable and representative results. This work establishes the methodological foundations necessary for future multi-taxon chemotaxonomic studies using O-PTIR.

The phylogenetic placement of unicellular microfossils is commonly impeded by limited diagnostic morphology. This leads to ever-expanding informal “wastebasket” taxa—such as acritarchs (Eukaryota; >10k species with predominantly Paleozoic occurrences)—with restricted evolutionary value. Vibrational spectroscopy-based chemotaxonomy offers a promising yet underexplored alternative for acritarch placement through organic wall biosignature matching with known clades. Here, we establish a chemotaxonomic framework applicable in deep time based on an unprecedented infrared spectroscopy dataset of >500 Ordovician–Quaternary unicellular eukaryotic palynomorphs, including phycomata of prasinophyte green algae, dinoflagellate cysts, bisaccate pollen, trilete spores, and acritarchs.

Using single-specimen attenuated total reflection, and transmission Fourier transform infrared microspectroscopy (µ-FTIR), we systematically track diagenetic and catagenetic transformations of the lineage-specific wall biopolymers—algaenan (green algae), dinosporin (dinoflagellate cysts), and sporopollenin (plant pollen and spores)—across modern, experimentally matured, and fossil material. Despite progressive macromolecular homogenization driven by temperature-induced defunctionalization and aromatization, phylogenetically informative spectral features survive fossilization and enable robust discrimination between biopolymer classes.

Paleozoic acritarch biosignature matching reveals affinities with green algae and dinoflagellates, demonstrating acritarch polyphyly and providing the first direct macromolecular evidence for pre-Triassic dinoflagellates facilitating the resolution of a >200 million year ghost lineage predicted by molecular clocks. These results demonstrate that µ-FTIR can be applied to decode the hidden diversity and deep evolutionary history of extinct unicellular eukaryotic life. Our methodological approach, when applied at a broader scale, allows to effectively counter the expansion of wastebasket taxa, as well as map out the fate of organic matter in the fossil record.

Acritarchs are an important component of Palaeozoic (micro-)fossil assemblages. Although they are commonly regarded as phytoplankton, their biological affinities are by definition unknown, and consequently their exact role in ancient ecosystems is uncertain as well. Some acritarchs from the Cambrian onwards show similarities with certain cysts of dinoflagellates, which today are one of the major phytoplankton groups but are only unequivocally known since the Triassic. It seems likely that some acritarchs represent precursors of this group but lack key characteristics of dinoflagellate cysts, such as paratabulation, a cingulum or an archaeopyle. Molecular clocks and organic geochemical analyses also support the presence of dinoflagellates in the early Palaeozoic. We aim to elucidate the biological affinity of acritarchs through the systematic study of acritarchs and dinoflagellates in terms of morphology and palaeobiochemistry. We use Fourier-transform infrared (FTIR) spectroscopy for chemotaxonomy alongside morphological comparisons to test possible phylogenetic relationships. Through the infrared spectra of isolated specimens, different biopolymers and ratios between functional groups can be identified. This provides evidence for both biological affinities and diagenetic alterations. The studied material comes from various Palaeozoic deposits with low thermal maturity, such as the Lower Silurian Visby beds of Gotland, Sweden. Here, a wide variety of both stratigraphically constraint and long-ranging, widely occurring acritarch taxa (e.g., Diexallophasis, Domasia, Micrhystridium, Multiplicisphaeridium, Veryhachium, Visbysphaera) are analysed along with forms that are commonly considered to represent prasinophycean algae, such as Cymatiosphaera and Dictyotidium.

Two new, closely related taxa of Normapolles flowers are presented. The specimens are preserved as charcoal and morphological and anatomical investigations of the fossil flowers were carried out using scanning electron microscopy and X-ray micro–computed tomography.

The North American material comes from Upatoi Creek on Fort Benning: a diverse and well-preserved late Santonian (Late Cretaceous) mesofossil assemblage from central Georgia, USA. The flowers are epigynous, bisexual with a one-whorled perianth and likely ten stamens with basifixed anthers. The syncarpous bicarpellate gynoecium has two styles, the ovary is unilocular and contains a single seed in fruit. Seeds are apically attached. The epidermis of the apical part of the ovary is covered with numerous simple trichomes.

The European material stems from the Klikov Formation (upper Turonian – Santonian age) from the locality Dobrá Voda near České Budějovice, Czech Republic. The floral structure is basically identical to the North American taxon with the exception of the androecium likely has twelve stamens and the ovary surface shows distinct longitudinal ribs extending from the base to the hypanthium.

Both taxa are considered related to the Normapolles complex. Although typical Normapolles pollen (triangular, triaperturate) was absent and the only preserved anther of the American material was immature with no pollen found, the epigynous structure of the flowers, with tepals and stamens associated with a hypanthium, as well as the bicarpellate-syncarpous gynoecium containing a single seed support their affiliation or close relation to this complex.

The Horseshoe Canyon Formation of southern Alberta, Canada, preserves abundant plant fossils from the upper Campanian to lower Maastrichtian, but its macroflora is taxonomically outdated and underutilised for palaeoclimatic reconstruction. We documented fifty-eight plant taxa from the Morrin Bridge locality in the lower Maastrichtian Horsethief Member. The assemblage comprises diverse gymnosperms, particularly Cupressaceae, alongside cycadophytes and ginkgophytes, rare ferns, and diverse angiosperms, including Platanaceae, Cercidiphyllaceae, Trochodendraceae, Betulaceae, multiple indeterminate dicots, and two monocots. Leaf physiognomic palaeoclimate analyses and closest climatic analogue comparisons reveal a temperate oceanic to warm-summer humid continental climate. Net primary productivity estimates are consistent with a temperate seasonal forest or woodland/shrubland biome. Collectively, these results indicate a warm-temperate, humid, frost-free climate characterised by moderate thermal seasonality and limited precipitation seasonality, consistent with conifer-dominated temperate floodplain forests with a diverse angiosperm component. The climatic reconstructions align with palaeosol and sedimentological evidence for saturated floodplain environments transitioning toward thicker and more frequent palaeochannels, suggesting increasingly active fluvial conditions and an intensified hydrological regime relative to earlier deposits of the Horsethief Member. This assemblage provides an important baseline for refining regional palaeoecological reconstructions of Late Cretaceous vegetation in Alberta in the lead-up to the K–Pg extinction and offers environmental insight into dinosaur palaeoecology within the Horseshoe Canyon ecosystem.

Latest Maastrichtian ecosystems remain central to debates surrounding dinosaurian diversity and ecological resilience prior to the Cretaceous–Palaeogene (K–Pg) mass extinction. However, relatively few studies have examined how floral turnover influenced trophic interactions and ecosystem structure immediately prior to the Chicxulub impact. Here, we reconstruct ecosystem-scale trophic networks from the Hell Creek Formation using the R package cheddar and an integrated palaeofloral and vertebrate dataset spanning the final ~2 million years of the Cretaceous. For the first time, explicit taxon-level trophic links between plants, herbivores, and higher consumers were reconstructed across the Hell Creek ecosystem using a functional trait-based framework incorporating feeding and growth height, browsing selectivity, inferred oral processing capabilities, along with mechanical toughness. Floral data were synthesized from both megafloral and palynological records across all recognised Hell Creek megafloral zones, reducing preservational bias and allowing reconstruction of temporal changes in vegetation structure and composition.

Our results indicate increasing abundance of mechanically tougher and woodier shrubs through the middle and upper Hell Creek succession, suggesting greater structural complexity within the herb–shrub layer. These changes in the most intensely browsed upon plant strata correspond with restructuring of herbivore guilds and shifts in niche partitioning. Broad-spectrum megaherbivores such as ceratopsids and Edmontosaurus annectens remained comparatively resilient, whereas intermediate selective browsers, including nodosaurids and some pachycephalosaurids, appear disproportionately affected by increasing niche compression and resource overlap. These results suggest latest Maastrichtian ecosystems were undergoing ecological restructuring prior to the K–Pg boundary rather than uniform ecological decline.

The Cretaceous–Paleogene (K–Pg) transition marked a major ecological reorganization that reshaped South American forests. Latest Cretaceous and earliest Paleogene paleofloras reveal strong geographic variation in vegetation composition and recovery following the end-Cretaceous extinction. In Patagonia, Late Cretaceous forests were dominated by Cheirolepidiaceae, Araucariaceae, and Podocarpaceae, accompanied by ferns, tree ferns, and diverse angiosperms, including Proteaceae, Cunoniaceae, and early Nothofagaceae and the extinct Normapolles and Triprojectacites complexes. Central and northwestern Argentine floras document mixed angiosperm–conifer communities, whereas contemporaneous floras from Brazil indicate increasingly tropical vegetation with conifers, palms, and diverse flowering plants. Paleocene records from Peru, Bolivia, Venezuela, and Colombia document the expansion of tropical lowland forests rich in palms, legumes, and Lauraceae. Colombian assemblages preserve the oldest known Neotropical rainforest, demonstrating the rapid establishment of complex rainforest ecosystems after the K–Pg event. By the early Eocene, South American forests reached exceptional diversity. Patagonian paleofloras record warm-temperate to subtropical rainforests containing lineages now centered in Southeast Asia and the western Pacific, including Casuarinaceae, Castanopsis, Eucalyptus, and several conifers. These assemblages reveal remarkable biogeographic connections among South America, Antarctica, Australasia, and Southeast Asia during the early Paleogene. At the same time, Patagonian forests retained characteristic Gondwanan elements, including Araucariaceae, Podocarpaceae, Proteaceae, Cunoniaceae, and Nothofagaceae. Together, South American fossil forests record heterogeneous responses to the K–Pg extinction, from the persistence of conifer-rich Gondwanan communities in the south to the diversification of angiosperm-dominated rainforests in tropical regions, illuminating the origins and the dynamic assembly of Southern Hemisphere forests.

This presentation explores how temperature variation influences Fourier Transform Infrared (FTIR) spectra of sporopollenin, and the implications for palaeoecological and taxonomic research. Previous studies on fresh pollen have shown that climatic conditions during pollen’s formation leave a measurable imprint on FTIR spectra, with heat stress producing distinct chemical changes. However, the extent to which temperature affects the chemistry of sporopollenin, the resistant outer wall of pollen grains that lacks any organic compounds, remains poorly understood.

To address this, seeds of Microseris walteri (Asteraceae) and Anthosachne scabra (Poaceae) from the Australian National Seed Bank, together with Hordeum murinum (Poaceae) from the Royal Botanic Gardens, Kew, were cultivated under three controlled climate scenarios representing environmental conditions in southern Australia: warm (27°C), intermediate (20°C), and cold (16°C). Pollen from each taxon was analysed using FTIR spectroscopy to identify temperature-related variations in absorbance, and these trends were compared with herbarium specimens of the same taxa collected under differing bioclimates.

Results show consistent temperature-driven changes in absorbance at several wavenumbers associated with sporopollenin chemistry. Similar spectral trends were observed in both experimentally-grown and herbarium-collected pollen. These environmental influences may partially obscure species-specific taxonomic signals and contribute to classification patterns. However, Random Forest classification models indicated that classification errors could not be explained solely by temperature effects. Overall, this study highlights the importance of accounting for environmental variation when interpreting pollen FTIR spectra. It also demonstrates the value of integrating experimental growth studies, which enable us to track how environmental signals interfere with the taxonomic signature.

Reconstructing past mountain elevations is challenging and critical for understanding how biodiversity responds to landscape and habitat changes. We demonstrate the potential to reconstruct past elevation profiles by measuring the abundance of ultraviolet-B (UV-B; 280–315 nm)- absorbing chemical compounds produced in the outer walls of plant pollen grains. Our analysis, based on a large dataset of nearly 2000 pollen grains from the Himalaya and Hengduan Mountains, reveals that the chemical compounds in the pollen wall scale predictably with elevation and insolation. These signals are also well preserved in fossil sporomorphs (pollen and spores) over long timescales, allowing their likely elevations to be inferred by comparison with a modern pollen reference. Our study establishes a solid first step: UV-B-absorbing chemical compounds in the pollen wall can serve as a novel proxy for paleoelevation reconstructions of mountains, thereby opening a new research avenue.

Ultraviolet-B (UV-B) radiation and its variation on the ground acts as regulator and stressor for terrestrial ecosystems. This study investigates variability in past surface UV-B radiation in northwest England during the Common Era by analysing ultraviolet-absorbing compounds (UACs) in sub-fossil Sphagnum spores extracted from a Late Holocene peat bog. We present a bidecadally-resolved record of UACs for the last 2600 years, providing first insights into past surface UV-B radiation. We compare our record with a previous, highly-resolved record of Sphagnum leaf δ18O and bog surface wetness, and find a significant correlation where lower UAC signals are found during wetter bog conditions, indicating associations between radiative and drought forcing. We also find that some UAC minima correspond to recognised Grand Solar Minima in late Holocene, but this association is not consistent across the whole timescale investigated. Our findings suggest more complex mechanisms underlying the relationship between solar activity and Sphagnum UACs. The research contributes to understanding the complex interplay between solar forcing, climate dynamics, and surface UV-B radiation over peatlands.

Solar Energetic Particle (SEP) events can deplete stratospheric ozone and elevate surface UV-B radiation. The 774/775 CE event was the most extreme SEP of the past 11,000 years, yet evidence of its biological impact remains lacking. Here we present an unprecedented annually resolved reconstruction of variations in surface UV-B variability as detected via the analysis of UV-B absorbing compounds (UACs) from Pinus pollen recovered from varved lake sediments.

The record, spanning 764–783 CE, captures a sinusoidal pattern consistent with Schwabe cycle-modulated surface UV-B variability. Superimposed on this signal is an abrupt increase in UAC abundance in pollen recovered from samples dated to 776–777 CE, coinciding with 14C and 10Be anomalies associated with the SEP event. This UAC spike is likely explained by plants’ responses to short-term elevated surface UV-B driven by NOx-induced ozone depletion following the event, with effects persisting beyond a year. The timing of the event during a Schwabe cycle minimum supports recent studies suggesting its occurrence during a solar minimum rather than a solar maximum.

Exposure to excess UV-B radiation can harm organisms through DNA damage and oxidative stress, and has likely been a key ecological and evolutionary driver throughout Earth’s history. Here, we show UV-B at Earth’s surface was significantly increased during the Laschamps Event, the last major geomagnetic excursion ca. 41ka BP. During the Laschamps, we find significant and prolonged (lasting >600yrs) increases in UV-B absorbing compounds in subfossil Pinus Diploxylon pollen (e.g., 31% [95% CI 19-44] increase compared to 1.3ka BP). Furthermore, we identify a significant (negative) broader linear relationship (p<0.001) between UV-B absorbing compounds and the geomagnetic dipole moment extending over the past 65ka. Our results demonstrate an empirical link between surface UV-B and geodynamo strength, important for understanding our past and mitigating our potential future.

During 2016 and 2017 Yale Peabody Museum field expeditions in Petrified Forest National Park, Arizona, Division of Paleobotany had excavations in Crystal Forest, a new fossil plant locality in the Late Triassic Chinle Formation and collected more than 173 Equisetites specimens from a carbonaceous mudstone layer. The Equisetites is represented by well-preserved young shoots, stems, leaf sheaths, and nodal diaphragms. Two types of Equisetites were identified. One type is Equisetites bradyi with relatively thin stems, short free portions of the leaves, and clear commissural grooves gradually expanding upward. The other one is probably a new type with relatively thick stems, long free portions of the leaves, and narrow commissural grooves of almost constant width. In addition to Equisetites specimens, just one conifer leafy shoot megafossil specimen of cf. Pagiophyllum sp. was uncovered in the locality. The Equisetites-dominated, low-diversity assemblage probably indicates the floodplain paleoenvironment where Equisitites grew in shallow parts of streams, ephemeral ponds, and adjacent wetlands. Furthermore, piercing and sucking insect damage (DT77) was noticed in a stem specimen of E. bradyi. This is the first such report of piercing and sucking damage in the Triassic. This type of insect damage was possibly caused by sternorrhynchan hemipterans (scale insects) which might indicate the presence of a dry season in the winter during that time. The charcoal recovered from the carbonaceous mudstone layer also provides direct evidence of ancient wildfire which may support the presence of a dry season.

The Carnian Pluvial Episode (CPE) has been identified as a time of plant radiation and origination of new lineages, likely related to rapid changes from xerophytic to more hygrophytic floras. Increasing humidity, causally resulting from large igneous volcanism, is considered the likely trigger for the observed changes in terrestrial ecosystems. Understanding the cause and effects of the CPE on the plant realm requires the study of well-preserved plant fossil assemblages that are precisely aligned with the CPE. Some of the most iconic Carnian floras are located in the Alps, situated during the CPE in the northwestern margin of the Tethys. This includes the famous Lunz locality (Northern Calcareous Alps) with the so far most diverse and rich plant fossil assemblages, as well as the Raibl plant fossil assemblages (Carnic Alps) and Dibona and Monte Pora (Southern Alps). This climatic episode is also linked to worldwide amber discoveries. Integrated studies of palynomorphs and macro-remains reveal a variety of different plant fossil assemblages from highly diverse ones dominated by ferns and cycadophytes to plant fossil assemblages almost exclusively composed of conifers that show a mixture of predominantly late Palaeozoic (Majonicaceae, Voltziaceae), Mesozoic (Cheirolepidiaceae), and extant (Araucariaceae, Pinaceae, and Podocarpaceae) conifer families.

The Carnian stage is a milestone in the Mesozoic evolution of plants with the radiation of key conifer and fern groups, bennettites and Cheirolepidaceae, all temporally linked to the Carnian Pluvial Episode (CPE) in the Late Triassic. The CPE was a major hyperthermal event marked by climate and carbon cycle perturbations. Although widely studied, especially in the Western Tethys, patterns of climate and biotic change remain poorly understood. Here we demonstrate climatic and environmental perturbations during the Carnian based on the palynological study of five borehole successions from the Transdanubian Range. The early Carnian climate was characterized by a strong monsoonal regime with a mixture of hygrophyte and xerophyte floral elements, and the proliferation of the Enzonalasporites group. We found evidence for an early Carnian carbon cycle perturbation with a negative carbon isotope excursion (NCIE) and a short-lived proliferation of hygrophyte flora prior to the CPE but with smaller marine biotic impact. Floral turnover peaked in the late Julian with the expansion of hygrophyte lowland vegetation parallel with the demise of marine biota and primary producers. Floral response and carbon cycle trends show a decoupling from the early Tuvalian (early late Carnian) when palynological assemblages indicate gradual aridification despite episodes of carbon cycle instability and elevated clastic influx. This new view on terrestrial and marine biotic events in the Western Tethys points to an overall longer interval of environmental instability in the Carnian that climaxed during the early Julian NCIE, and in the late Julian during the peak CPE phase.

The Carnian Pluvial Episode (CPE) was a major Late Triassic climatic perturbation that reshaped terrestrial ecosystems. Yet subtropical plant communities along the northwestern Tethyan margin remain comparatively underdocumented, limiting reconstructions of low latitude vegetation. The Carnian outcrop of Neuewelt (near Basel, Switzerland) preserves a significant plant macrofossil assemblage from this region, offering new insight into the composition and structure of Late Triassic floras. Here we present a preliminary macromorphological revision of the historical Neuewelt collection, complemented by cuticular observations. The integration of macromorphology with epidermal features refines taxonomic assignments and informs plant diversity and ecological strategies within subtropical settings. The assemblage records a diverse flora, that includes lycophytes, ferns, sphenophytes, cycadophytes, seed ferns, and conifers, indicative of a structurally complex plant community. By combining macrofloral and cuticular data, this study improves taxonomic resolution and contributes to a more detailed reconstruction of Carnian subtropical vegetation along the northwestern Tethyan margin.

The Carnian, the basal stage of the Upper Triassic, is marked by an intermittent change in sedimentation style in various basins. This interval has been attributed to a climatic upheaval termed the Carnian Pluvial Episode, a time of increased humidity and runoff (Simms & Ruffell, 1989). Here we compare the Carnian palynology of two sites. The first locality is Neuewelt situated near Basel in Switzerland representing the fluvially deposited sediments (Ergolz Member of the Klettgau Formation) at the southern margin of the Central European Basin. There, particulate organic matter is characterized by strong dominance of phytoclasts. The spore and pollen content is marked by high relative abundance of spores and very high diversity of spore taxa. The other locality is Heiligkreuz/Santa Croce near Badia in the Dolomites of Italy, representing the marginal marine sediments (lower part of the Heiligkreuz Formation) of the northern Tethyan ocean. The depositional environment contrasts to Neuewelt in lower relative abundances of phytoclasts, and varying contents of aquatic organic particles. The spore and pollen assemblages in the Dolomites are marked by high relative abundance of low diverse gymnosperm pollen taxa.