Browsing {{ collection }} by Author "Munyikwa, Darlington"
Now showing 1 - 2 of 2
- Results Per Page
- Sort Options
Item Cranial morphology of a primitive dinocephalian from the Madumabisa Mudstone Formation, Zimbabwe(2001) Munyikwa, DarlingtonDinocephalians 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.Item Further material of the ceratosaurian dinosaur Syntarsus from the Elliot Formation (Early Jurassic) of South Africa(Bernard Price Institute for Palaeontological Research, 1999) Munyikwa, DarlingtonTwo further fossils recovered from the Elliot Formation in South Africa are referred to the ceratosaurian genus Syntarsus: a partial pelvis and a well preserved and articulated snout. The pelvic fragment consists of most of the posterior end of the left ilium and sacrum, with a small part of the right ilium attached. The acetabular area and ‘brevis shelf’ of the left ilium are well preserved, as is the ventral surface of the sacrum. These parts show features characteristic of Syntarsus material from Zimbabwe. The snout has the premaxillae, maxillae, nasals and dentaries from both sides preserved, of which only the premaxillae are more or less complete. The premaxilla has four alveoli and the maxilla nine, and the maxilla bears the characteristic dimpling on its lateral surface also seen in Syntarsus material collected in Zimbabwe. The snout also possesses the characteristic small diastema or subnarial gap between the premaxillary and maxillary teeth shown by Syntarsus material from elsewhere. The snout is strongly compressed bilaterally and the jaws are tightly closed, so that the dentary teeth are obscured beneath the upper dentition. This compression has crushed the palatal region, obscuring palatal details.