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Elliotherium kersteni, a new tritheledontid from the lower Elliot Formation (Upper Triassic) of South Africa

Published online by Cambridge University Press:  14 July 2015

C. A. Sidor  and
P. J. Hancox
C. A. Sidor
Affiliation:
Burke Museum and Department of Biology, University of Washington, Seattle 98195,
P. J. Hancox
Affiliation:
Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, Johannesburg, WITS 2050, South Africa,
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Abstract

We describe a new tritheledontid, Elliotherium kersteni n. gen. and sp., on the basis of a partial skull collected from the lower Elliot Formation (Upper Triassic; Euskelosaurus Range Zone) on the farm Beatrix, Free State Province, South Africa. Although similar to Pachygenelus, the genus differs from other South African tritheledontids in its higher maxillary postcanine tooth count, lack of labial cingula on the upper postcanine teeth, shorter secondary palate, retention of a median vomerine ridge behind the secondary palate, and smaller interpterygoid vacuity. With regard to these features, Elliotherium is most similar to the South American tritheledontid Chaliminia. Elliotherium is autapomorphic in its possession of a long parasphenoid rostrum, ventrally depressed secondary palate, medially convex margins of the interpterygoid vacuity, and a thin lamina of palatine covering the interpterygoid vacuity. Although Elliotherium is the stratigraphically lowest positioned tritheledontid from southern Africa, it is still probably later occurring than the South American taxa Chaliminia or Riograndia. Based on a revision of a previous analysis of advanced cynodont relationships, we propose a sister-group relationship between Elliotherium and Chaliminia, although support for this pairing is weak.

Type
Research Article
Information
Journal of Paleontology , Volume 80 , Issue 2 , March 2006 , pp. 333 - 342
Copyright
Copyright © The Paleontological Society 

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