Clevosaurus hudsoni (Swinton 1939) Carnian, Late Triassic ~200 mya, was a derived rhynchocephalian with teeth fused to one another and to the jaw bones. Derived from a sister to Brachyrhinodon.
The premaxilla rose posterior to the nares, which are elongated. The frontals are wider with posterior processes. The jugal does not contact the squamosal. The ilium is taller than long.