Leaving only trace fossils - the unknown visitors of Winterswijk

Abstract | The tetrapod tracks from Winterswijk receive global attention for their abundance and preservation quality, including long trackways and skin- and claw impressions. The footprint association is consistent with a Middle Triassic age. It includes four ichnotaxa: Brachychirotherium paraparvum, Rhynchosauroides peabodyi, Procolophonichnium haarmuehlensis and Coelurosaurichnus ratumensis. Their terrestrial producers probably include: archosauriforms, archosauromorphs/lepidosauromophs and both small and large therocephalian therapsids, respectively. These groups are almost completely unknown from the fossil (bone) record of the Vossenveld Formation, which includes mostly aquatic life-forms. The occurrence of vertebrate swimming traces and invertebrate tracks and burrows indicates a marginal marine palaeoenvironment, subject to frequent flooding and rapid drying (tidal fl at).