Abstract
Clevosauridae (Lepidosauria, Rhynchocephalia) was a clade of Sphenodontia considerably abundant during the early Mesozoic. Clevosaurus represents the most diverse and broadly distributed genus among the group, with species ranging from the Upper Triassic to the Lower Jurassic. In the deposits of the Upper Triassic of South America (Rio Grande do Sul, Brazil), two species of Clevosaurus ar…