Tanystropheids from the Winterswijk quarry - rare but recurring elements

Abstract

Tanystropheids were archosauromorph reptiles from the Triassic characterized by long necks composed of elongate cervical vertebrae and ribs, as is epitomized by its most recognisable genus Tanystropheus. An isolated cervical vertebra from the Winterswijk quarry was assigned to Tanystropheus antiquus in 1984. However, the genus Tanystropheus has been repeatedly revised and the taxonomic status of Tanystropheus antiquus has been questioned since. Furthermore, the taxonomic affi nity of the growing body of tanystropheid material from Winterswijk has not formally been investigated, rendering the identity of tanystropheid material from the Vossenveld Formation uncertain. We present an overview of the taxonomic history of Tanystropheus in order to clarify the identifi cation of tanystropheid remains from the Lower Muschelkalk, including those from Winterswijk. Furthermore, we present and describe several previously unpublished tanystropheid specimens from the Winterswijk quarry. Although conclusive taxonomic assignment of exclusively isolated elements is problematic, all presented cervical vertebrae are tentatively assigned to ‘Tanystropheus antiquus’. The other unequivocally tanystropheid remains, two cervical ribs and a dorsal vertebra, are identifi ed as Tanystropheus sp.