A new burnetiamorph therapsid from the Teekloof Formation, Permian, of South Africa

Abstract

ABSTRACT A new biarmosuchian therapsid, Lobalopex mordax gen. and sp. nov., from the Permian Teekloof Formation (Tropidostoma Assemblage Zone) of the Victoria West District, South Africa, is described on the basis of a partial skull with lower jaws and the first four cervical vertebrae. The genus is diagnosed by the following autapomorphies: median nasal eminence low and ridge-like; supraorbital boss small and unpachyostosed; posteriorly projecting supratemporal ‘horns’ present but relatively small; ventral surface of transverse flange of pterygoid edentulous and sharply ridged; and laterally-directed knob present lateral to contact between pterygoid and palatine dentigerous bosses. As in some other biarmosuchians, the cervical vertebrae are elongated, being roughly twice as long as they are wide or deep. A cladistic analysis including ten biarmosuchian taxa indicates that Lobalopex is the sister taxon to Burnetiidae and that Lemurosaurus is the most primitive burnetiamorph. These results fail to provide evidence for geographic endemism in these groups of Middle to Late Permian therapsids.