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South African Journal of Science
versão On-line ISSN 1996-7489
versão impressa ISSN 0038-2353
S. Afr. j. sci. vol.103 no.1-2 Pretoria Jan./Fev. 2007
RESEARCH LETTERS
A double-tusked dicynodont and its biostratigraphic significance
Zubair Ali JinnahI; Bruce RubidgeII
ISchool of Geosciences, University of the Witwatersrand, Private Bag 3, WITS 2050, South Africa
IIBernard Price Institute (Palaeontology), School of Geosciences, University of the Witwatersrand
ABSTRACT
A new specimen of Eodicynodon oosthuizeni, discovered near Prince Albert Road in the Western Cape province of South Africa, has a double distinction. Of stratigraphic importance is the fact that it is the only specimen of Eodicynodon known from above the first maroon mudrocks of the Beaufort Group, a feature which has important implications for understanding the development of the earliest terrestrial environments of Gondwana during the middle Permian. Of anatomical significance is the presence of two canines on the left maxilla. This rare condition, known in only three dicynodonts, is here considered to be pathological and not the result of tooth replacement.
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Received 27 November 2006.
Accepted 28 February 2007.
* Author for correspondence. E-mail: bruce.rubidge@wits.ac.za