A non-mammaliaform cynodont from the Upper Triassic of South Africa: a therapsid Lazarus taxon?
Date
2007
Authors
Abdala, Fernando
Damiani, Ross
Yates, Adam
Neveling, Johann
Journal Title
Journal ISSN
Volume Title
Publisher
BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH
Abstract
The tetrapod record of the ‘Stormberg Group’, including the Lower Elliot Formation, in the South African Karoo is widely dominated by
archosaurian reptiles, contrasting with the therapsid dominion of the subjacent Beaufort Group. The only therapsids represented by
skeletal remains in the Upper Triassic Lower Elliot Formation are the large traversodontid cynodont Scalenodontoides macrodontes and
the recently described tritheledontid cynodont Elliotherium kersteni. Here we present a fragmentary lower jaw that provides evidence of
a 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 is known from 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 South Africa, 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.