Browsing by Author "Rubidge, Bruce S."

Now showing 1 - 9 of 9
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    Assessing content and bias in South African Permo-Triassic Karoo tetrapod fossil collections
    (Bernard price Institute for Palaeontological Research, University of the Witwatersrand, 2009-12) Nicolas, Merrill; Rubidge, Bruce S.
    A standardized taxonomic database as well as a Geographical Information System (GIS) database of all fossil tetrapods collected from the Permo-Triassic Beaufort Group rocks of South Africa has been compiled from a number of South African museum catalogues. The data capture required rigorous evaluation of the accuracy of the original records and the degree of collecting bias. The outcome of this evaluation endorsed the accuracy of the two databases and showed no significant degree of collecting bias. This standardized database, now linked to a new GIS-based database, will be a valuable resource to scientists researching Permo-Triassic biodiversity and faunal distribution patterns.
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    Biesiespoort revisited: a case study on the relationship between tetrapod assemblage zones and Beaufort lithostratigraphy south of Victoria West
    (Evolutionary Studies Institute, 2018-12) Day, Michael O.; Rubidge, Bruce S.
    The relationship between the tetrapod assemblage zones of the South African Karoo Basin and the lithostratigraphic divisions of the Beaufort Group is well-established, and provides an independent means of dating fossil occurrences. However, this relationship may not be consistent across the basin; a discrepancy exists between the historical tetrapod assemblages in the vicinity of Victoria West, Northern Cape Province, and the expected tetrapod assemblage zones based on mapped geology. In order to examine this disconnect, we collected fossils at two localities close to Biesiespoort railway station, a locality that was visited on a number of occasions by Robert Broom. Our fossil samples support the biostratigraphic determinations of Broom and thus confirmthat the stratigraphic extent of the biozones at these localities differs from their type areas further south. The reasons for this are unclear but could be related to the northward younging of the lithological units, implying complex depositional processes, or result from difficulties in mapping. Nevertheless, caution should be exercised when using mapped geology near Victoria West as a guide to the age of fossils found there.
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    The BPI - 50 years of palaeontological activity
    (Bernard Price Institute for Palaeontological Research, 1997) Rubidge, Bruce S.
    The Bernard Price Institute for Palaeontological Research at the University of the Witwatersrand was established from an endowment made by Bernard Price in 1945. Now, a mere 50 years later, the Institute ranks as a prominent palaeontological research centre in Africa. It curates large collections of fossils including Karoo reptiles, mammals from the Makapansgat valley and other Plio-Pleistocene sites, invertebrates from the Bokkeveld and Zululand, and has a large palaeobotany herbarium. The Institute produces the journal Palaeontologia africana, the only journal in Africa dedicated to the publication of palaeontological papers. The BPI is closely affiliated to the Department of Palaeontology and Palaeoenvironmental Studies, the only department of palaeontology at a South African University. During the 50 years of its existence the BPI has played an important role in the advancement and dissemination of palaeontological knowledge in southern Africa.
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    Cranial morphology and taxonomy of South African Tapinocephalidae (Therapsida: Dinocephalia): the case of Avenantia and Riebeeckosaurus
    (Evolutionary Studies Institute, University of the Witwatersrand, 2013-12-18) Guven, Saniye; Rubidge, Bruce S.; Abdala, Fernando
    Tapinocephalid dinocephalians comprise a large component of Middle Permian herbivorous tetrapod biodiversity and are significantly abundant in the Karoo rocks of SouthAfrica. In order to understand the effect of the alleged Middle Permian extinction in the terrestrial record of amniotes a clear understanding of the taxonomic diversity of this group is essential. The tapinocephalids Avenantia kruisvleiensis and Riebeeckosaurus longirostris have in the past been distinguished by a set of characters, including differences in the snout length which was previously interpreted as a key diagnostic character. Further preparation of the material attributed to these species shows that the purported distinguishing characters, such as snout length, low intertemporal crest, and surface thickening of the parietal represent postmortem deformation (including distortion and weathering) or can be interpreted as individual or ontogenetic variation. Accordingly A. kruisvleiensis is synonimized with R. longirostris.
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    James William Kitching (1922–2003): a tribute
    (BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2005) Raath, Michael A.; Rubidge, Bruce S.
    On 24 December 2003, James William Kitching, regarded by many as one of the world’s greatest fossil finders, died at his home in Johannesburg. His passing marks the end of a pioneering era of palaeontological giants in South Africa.
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    The oldest Procolophonoid (Amniota: Parareptilia) - New discovery from the lower Beaufort of South Africa.
    (Bernard Price Institute for Palaeontological Research, 1997) Gow, Chris E.; Rubidge, Bruce S.
    Until now the earliest recognised procolophonoid (sensu Laurin & Reisz 1995) reptile has been Owenetta, which ranges from the Cistecephalus assemblage zone (Upper Permian) to the Lystrosaurus assemblage zone (Lower Triassic) of the Beaufort Group of South Africa. This paper records the presence of a new even older form from low in the underlying Tapinocephalus assemblage zone.
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    Postcranial morphology of the South African middle Permian pareiasaurs from the Karoo Basin of South Africa
    (Evolutionary Studies Institute, 2021-05-28) van den Brandt, Marc J.; Benoit, Julien; Abdala, Fernando; Rubidge, Bruce S.
    Pareiasaurs were relatively abundant and globally distributed herbivorous parareptiles of the middle to late Permian. The basal-most pareiasaurs, the Bradysauria, are restricted to the middle Permian of South Africa and went extinct at the end of the Guadalupian (Capitanian) at the top of the Tapinocephalus Assemblage Zone. Currently, three genera are recognized in this group: Bradysaurus, Embrithosaurus and Nochelesaurus, but their postcrania are poorly known, and consequently poorly understood. In this paper, our third contribution designed to improve understanding of the Bradysauria, we present a detailed comparative postcranial description and updated diagnoses for Bradysaurus baini, Embrithosaurus schwarzi and Nochelesaurus alexanderi. Bradysaurus baini has one postcranial autapomorphy: anterior dorsal osteoderms smooth and strongly convex, with an incipient central boss, and very light ornamentation. Three pelvic autopomorphies of Embrithosaurus schwarzi are confirmed: anterior portion of the iliac blades flat and vertical (not everted or upturned); iIiac blades diverge anteriorly, oriented at 45–60° off the sagittal plane; and a very thick pelvic symphysis. For Nochelesaurus alexanderi we remove all three of the postcranial autapomorphies previously proposed. To the diagnoses of each species, we have added several new distinguishing postcranial features, within the local group of middle Permian pareiasaurs. The results reinforce our previous cranial studies concluding that three valid species of pareiasaurs are represented in the South African middle Permian.
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    The postcranial skeletal anatomy of the therocephalian Regisaurus (Therapsida: Regisauridae) and its utilization for biostratigraphic correlation
    (BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Fourie, Heidi; Rubidge, Bruce S.
    The postcranial morphology of the therocephalian genus Regisaurus from the Lystrosaurus Assemblage Zone of South Africa is described. The remarkably complete state of preservation of the vertebral column has, for the first time, provided a full vertebral count for a therocephalian and demonstrates that it is possible to differentiate between cervical, thoracic, lumbar, sacral and caudal vertebrae. It is demonstrated that some postcranial elements can be used to identify particular therocephalian groups and will be of use in biostratigraphic studies in areas where cranial remains have not been found. A slender scapula, low scapular ridge, shallow scapular depression, short and broad interclavicle, oval sternum, and a small obturator foramen are characteristics of therocephalians known from the Cistecephalus, Dicynodon and Lystrosaurus assemblage zones of the Beaufort Group of South Africa.
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    The postcranial skeleton of the basal therocephalian Glanosuchus macrops (Scylacosauridae) and comparison of morphological and phylogenetic trends amongst the Theriodontia
    (Bernard Price institute for Palaeontological Research, University of the Witwatersrand, 2009-12) Fourie, Heidi; Rubidge, Bruce S.
    The postcranial morphology of the early scylacosaurid therocephalian Glanosuchus macrops from the Pristerognathus Assemblage Zone of the Beaufort Group is described and compared with that of later therocephalians. This database is used as a basis to identify postcranial differences between therocephalians, gorgonopsians and cynodonts in an attempt to increase understanding of the postcranial anatomy of theriodont therapsids. It is demonstrated that some postcranial elements can be used to identify particular theriodont groups. The T-shaped interclavicle, absence of ossified sternum, humerus without shaft area, and large pubic foramen are characteristics of therocephalians from the Tapinocephalus Assemblage Zone of the Beaufort Group of South Africa.