Palaeontologia africana

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ISSN (print): 0078-8554 ISSN (electronic): 2410-4418 For queries regarding content of Palaeontologia africana collections please contact Jonah Choiniere by email : jonah.choiniere@wits.ac.za or Tel : 011 717 6684

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    First occurrence of the dicynodont Digalodon (Therapsida, Anomodontia) from the Lopingian upper Madumabisa Mudstone Formation, Luangwa Basin, Zambia
    (Evolutionary Studies Institute, 2019-04) Angielczyk, Kenneth D.
    Digalodon is a rare emydopoid dicynodont first described from upper Permian rocks in the Karoo Basin of South Africa. During fieldwork in the upper Madumabisa Mudstone Formation of the Luangwa Basin (Zambia) in 2014, a small dicynodont skull was discovered that conforms very well to the recently revised diagnosis of Digalodon rubidgei, although some minor differences between the Zambian and South African specimens are apparent. The Zambian occurrence of Digalodon expands the known geographic range of the genus, which was previously limited to a small set of localities in the vicinity of the town of Graaff-Reinet (Eastern Cape). Based on historical specimens, Digalodon is thought to have a comparatively short stratigraphic range in the Balfour Formation that spans the boundary between the Cistecephalus and Daptocephalus assemblage zones. This observation may allow refinement of biostratigraphic correlations between the Karoo and Luangwa Basins, but discovery of more precisely-provenanced specimens in the Karoo is needed to fully assess Digalodon’s biostratigraphic utility.
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    The first skeletal evidence of a dicynodont from the lower Elliot Formation of South Africa
    (Evolutionary Studies Institute, 2018) Kammerer, Christian F.
    Historical fossil specimens from the lower Elliot Formation are identified as representing a large-bodied dicynodont, the first known from skeletal material in the Late Triassic of South Africa. Although fragmentary, these fossils differ from all other known Triassic dicynodonts and are here described as a new taxon, Pentasaurus goggai gen. et sp. nov. Pentasaurus can be distinguished from other Triassic dicynodonts by a number of mandibular characters, most importantly the well-developed, unusually anteriorly-positioned lateral dentary shelf. Phylogenetic analysis indicates that Pentasaurus is a placeriine stahleckeriid. Placeriines include the latestsurviving dicynodonts but their remains are primarily known from the Northern Hemisphere, with their only previously-known Southern Hemisphere representative being the Middle Triassic Zambian taxon Zambiasaurus. The discovery of a placeriine in the Late Triassic of SouthAfrica supports recent proposals that local climatic conditions, not broad-scale biogeographic patterns, best explain the observed distribution of Triassic tetrapods. The tetrapod fauna of the lower Elliot Formation is highly unusual among Triassic assemblages in combining ‘relictual’ taxa like dicynodonts and gomphodont cynodonts with abundant, diverse sauropodomorph dinosaurs.
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    Postcranial evidence for the evolution of the Black Wildebeest, Connochaetes gnou: an exploratory study
    (Bernard Price Institute for Palaeontological Research, 1993) Brink, James S
    Black wildebeest fossils from the interior of South Africa and the Cape coastal zone are compared to modern specimens in order to trace the pattern of morphological change and the distribution of the species through time. Measurements taken on selected postcranial skeletal elements, i.e. the axis and metapodials, suggest that the evolution of the black wildebeest was marked by a general reduction in body size. It appears that the evolution of Connochaetes gnou from a blue wildebeest-like (C. taurinus) ancestor is best documented in areas to the south of the Vaal River. Although the geographic range of the two temporal subspecies of C. gnou (C. gnou laticornutus and C. gnou antiquus) included the Cape ecozone, the reduction in body size appears to have beeen accelerated in the Cape coastal zone where in the Last Glacial sensu lato there was a regionally distinct population. This population, of smaller body size than extant populations, became extinct at the end of the Last Glacial with the onset of higher sea levels.