Shell anatomy of the African Paleocene bothremydid turtle Taphrosphys congolensis and systematic implications within Taphrosphyini

The bothremydid pleurodiran turtle Taphrosphys congolensis is a member of Taphrosphyina from the Paleocene of the Cabinda Province (Congo Basin, Angola). Very few specimens corresponding to elements of its shell have been so far figured. Abundant unpublished remains are analyzed in this paper. As a consequence, several regions of the shell are figured and characterized here for the first time, and intraspecific variability is recognized for several characters. Previous authors proposed some putative differences between the shells of Taphrosphys congolensis and the North American Paleocene Taphrosphys sulcatus. The increase in the knowledge about the shell of this African form allows us to refute most of them, the shell of both forms being recognized as more similar than previously identified. Thus, the identification of the genus Taphrosphys as restricted to three forms (i.e. the skull taxon Taphrosphys ippolitoi, and the skull and shell forms T. congolensis and T. sulcatus) is supported, and the record unquestionably attributable to this genus is modified from the Upper Cretaceous-Eocene lapse of time to the Paleocene exclusively.