A tetrapod swimming traceway from the Triassic of Winterswijk, the Netherlands

Abstract We describe a tetrapod swimming traceway from the Middle Triassic Vossenveld Formation of the Netherlands. Forty-five individual traces, each consisting of two parallel claw drag marks, were followed over 9 m in a roughly east–west direction. The asymmetry of the traceway geometry indicates the trace maker negotiated a lateral current. The trace maker could not be identified, but the traces described here are markedly different from Dikoposichnus traces attributed to swimming nothosaurs.