A new species of Saurichthys (Actinopterygii: Saurichthyidae) from the Middle Triassic of Winterswijk, The Netherlands

The Lower Muschelkalk Vossenveld Formation has yielded a diverse and abundant vertebrate fauna. In this contribution, we describe a small saurichthyid fish, Saurichthys dianneae sp. nov., from the Winterswijk locality in the eastern Netherlands. This species is represented by multiple specimens ranging from the Bithynian to the early Illyrian (middle - early late Anisian) in age. The material from Winterswijk includes articulated postcranial material, which is unusual for a saurichthyid from the Muschelkalk. Saurichthys dianneae sp. nov. is diagnosed by its small size (less than 10 cm in total length), elongate shape, extremely constricted interorbital region, neural arches lacking well-developed neural spines, and morphology and organization of the squamation. The slender body shape, flattened upper jaw, and dorsally directed orbits suggest that S. dianneae may have lived near the sea surface. Saurichthys with a similar body shape are known from the Middle Triassic of Germany, and indicate that these small, surface-dwelling saurichthyid fishes may have been widespread in coastal areas of the Middle Triassic Muschelkalk Sea.