Sprecher
Beschreibung
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 the Allon flora: 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.