M3#557_GSN F1591

Collection : Geological Survey of Namibia, Windhoek, Namibia

Inventory number : GSN F1591

Sex : indet

Age group : Adult

Age (if applicable) : Ladinian-Carnian

Material Type : Skull, cervical vertebrae

Origin : Etjo Mountain, Waterg Plateau Park, Omingonde Basin, Central Northwest Namibia

Class : Therapsida

Order : Cynodontia

Family : Traversodontidae

Genus : Etjoia

Species :✝dentitransitus

A small-bodied cynognathian cynodont (~0.5 m) with the following autapomorphies among gomphodonts: (1) divergent first left and right lower incisor and bearing a small number of large apically oriented denticles; (2) four mesiodistally elongated subrectangular lower gomphodont postcanines; (3) third lower gomphodont postcanine with a prominent mesial cingulum disposed along the entire mesial margin of the crown as well as a small labiolingual constriction at mid-length on its basolingual side; (4) four distal upper and lower sectorial teeth in which the main cusp occupies the mesial half of the crown and includes a strongly distally projected apex; (5) fourth upper sectorial postcanine strongly lingually displaced. Etjoia can further be distinguished from all other cynodonts by a unique combination of characters: similar number of gomphodont and sectorial postcanines in the upper and lower jaws; oval upper gomphodont postcanines with a tall and centrally positioned central cusp on the transverse crest in the mesial gomphodont teeth; upper and lower sectorial teeth significantly larger (i.e. mesiodistally longer and apicobasally higher) than the gomphodont postcanines and devoid of labial or lingual platform/cingulum; maxilla lacking a labial shelf.