Article: Revision of Aptian thecideidine brachiopods of the Faringdon Sponge Gravels

The study of a new collection of thecideidine brachiopods from the Faringdon Sponge Gravels reveals the presence of two distinct forms, Bifolium faringdonense (Dav.) as interpreted by Pajaud (1970) and Neothecidella parviserrata sp. nov. It is believed that the previous confusion in the literature concerning the genus Bifolium Elliott, stems from Elliott's (1948) failure to appreciate that his proposed ontogenetic series embraced juveniles of more than one species. Despite Pajaud's proposal that Neothecidella should be restricted to Jurassic usage, the characters of the new species are so obviously neothecidelliform that it must be assigned to Neothecidella. It is considered that the ornament has some ecological significance and that the separation of the two Aptian genera on microstructural as well as morphological evidence has significant taxonomic and phylogenetic implication.