Eohyosaurus

Eohyosaurus is an extinct genus of basal rhynchosaur known from the early Middle Triassic (early Anisian stage) Burgersdorp Formation of Free State, South Africa. It contains a single species, Eohyosaurus wolvaardti.

Discovery
Eohyosaurus is known solely from the holotype SAM-PK-K10159, a partial skull missing the front end, with associated incomplete lower jaws currently housed at the Iziko South African Museum, Cape Town. The specimen was discovered by Frederik Petrus Wolvaardt in December 2000, loose on boulder-strewn slopes at the base of a cliff, at Farm Lemoenfontein 44, Rouxville District of the Free State Province. It was collected from the middle deposits of the Burgersdorp Formation of Beaufort Group. This horizon belongs to Subzone B of the Cynognathus Assemblage Zone, dating to the early Anisian stage of the early Middle Triassic period, about 246 million years ago. Farm Lemoenfontein 44 also yielded remains of the archosauriform Erythrosuchus africanus, the bauriid Microgomphodon oligocynus, the cynodont Trirachodon, the kannemeyeriid Kannemeyeria'' as well as unidentified procolophonid remains. All known basal rhynchosaurs came from similar deposits in the Beaufort Group, and while Howesia browni and Mesosuchus browni are also known from Subzone B of Burgersdorp Formation (from different localities), Noteosuchus colletti is known from the earliest Triassic Katberg Formation (Lystrosaurus Assemblage Zone).

Etymology
Eohyosaurus was first described and named by Richard J. Butler, Martín D. Ezcurra, Felipe C. Montefeltro, Adun Samathi and Gabriela Sobral in 2015 and the type species is Eohyosaurus wolvaardti. The generic name is derived from Greek eos, meaning "early"/"dawn", hyos, meaning "pig"/"hog", and sauros meaning "lizard", in reference to Eohyosaurus being one of the earliest stratigraphically occurring rhynchosaurs, a group commonly described as "pig-like reptiles". The specific name honors Frederik Petrus Wolvaardt who discovered the type specimen SAM-PK-K10159.