Sachs, S. (2005) Redescription of Elasmosaurus platyurus Cope 1868 (Plesiosauria: Elasmosauridae) from the Upper Cretaceous (lower Campanian) of Kansas, USA. Paludicola 5(3): 92-106.
—The type specimen of Elasmosaurus platyurus Cope, 1868 from the Upper Cretaceous (lower Campanian) of Kansas, U.S.A. is redescribed. It consists of part of the skull (e. g., both premaxillae, parts of the maxillae, the occipital condyle and parts of the dentaries), the almost complete vertebral column, including the atlas-axis complex, as well as the pectoral and pelvic girdles (although the latter are now lost). The genus Elasmosaurus can be defined by two unambiguous autapomorphies, the presence of six premaxillary teeth and the high number of 71 cervical vertebrae. It also exhibits a number of advanced features, which are discussed and compared with other elasmosaurs.
