A non-mammaliaform cynodont from the Upper Triassic of South Africa: a therapsid Lazarus taxon?

ABDALA, F.; DAMIANI, R.; YATES, A.; NEVELING, J.

Palaeontologia Africana

University of the Witwatersrand

Lugar: Johannesburgo; Año: 2007 vol. 42 p. 17 - 23

0078-8554

The tetrapod record of the ?Stormberg Group?, including the Lower Elliot Formation, in the SouthAfrican Karoo is widely dominated by archosaurian reptiles, contrasting with the therapsid dominion of the subjacent Beaufort Group. The only therapsids represented byskeletal remains in the Upper Triassic Lower Elliot Formation are the large traversodontid cynodont Scalenodontoides macrodontes and the recently described tritheledontid cynodont Elliotherium kersteni. Herewepresent a fragmentary lower jaw that provides evidence ofa third type of cynodont for the Upper Triassic of South Africa. The fossil is tentatively assigned to the Diademodontidae. The latter representative of this family isknownfrom the Late Anisian, and its tentative record in the Norian Lower Elliot Formation, if confirmed,will represent a case of Lazarus taxon. Thus, Diademodontidae apparently disappeared from the fossil record by the end of the Anisian and then reappeared in the Norian of SouthAfrica, a stratigraphic interval of some 21 million years. This new cynodont record, together with the recently described Tritheledontidae, show that cynodonts are now the second most  diverse tetrapod group in the Lower Elliot fauna.