The importance of Winterswijk for understanding placodontiform evolution

Abstract | Placodontiformes are basal, semi-aquatic sauropterygians that mostly preyed upon hard-shelled organisms and often had substantial dermal armour. While their fossil remains are rare, they can be found in Triassic sediments throughout Europe, the Middle East and southern China, often in the form of their unusually large, tablet-shaped teeth. Winterswijk, however, boasts one of the most important fossil records for placodontiforms in the world, with two unique genera that are not currently known from anywhere else: Palatodonta bleekeri and Pararcus diepenbroeki. Other than these, more widespread genera are probably also represented in the form of Placodus sp. and Cyamodus sp.