A dissertation submitted to the Faculty of Science, University of Witwatersrand,
Johannesburg, in fulfilment of the requirements for the degree of Master of Science.Dinocephalians form an important part of the Upper Permian therapsid faunas of South
Africa and Russia, and have also recently been reported from China and Brazil, and even
more recently a diverse dinocephalian fauna has been described from Zimbabwe. This
thesis reports a new primitive tapinocephalid dinocephalian, NHMB 1556, from the Upper
Madumabisa Mudstone Formation in Zimbabwe. NHMB 1556 is considered to be closely
related to Avenantia and it possesses primitive tapinocephalid characters, but is more
derived than Tapinocaninus, the most primitive tapinocephalid dinocephalian known.
NHMB 1556 is distinguished from other tapinocephalines by having a groove on the
squamosal below its dorsal contact with the parietal, a low squamosal-parietal suture on
the posterior border of the temporal fenestra, a vomer which extends posteroventrally and
forms the anterior margin of the interpterygoidal vacuity and basisphenoid, which is
semi-circular anteroventrally.AC201
