Wits Evolutionary Studies Institute (ESI)

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End date: 1989Subject: search.filters.subject.South Africa

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    A problematical element in the Glossopteris flora of Vereeniging
    (Bernard Price Institute for Palaeontological Research, 1975) LeRoux, S F
    An unusual element, not previously recorded from the mixed Glossopteris Flora of Vereeniging, is described here. The type material was obtained from a rich fossiliferous zone, previously described by the author (Le Roux, 1963, pp. 1-2). The material available for study consists of a single specimen of an incomplete frond preserved in the form of an impression in fine-grained laminated clay.
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    The morphology and relationships of Youngina capensis Broom and Prolacerta broomi Parrington
    (Bernard Price Institute for Palaeontological Research, 1975) Gow, Chris E
    Comprehensive descriptions of the osteology of Youngina capensis Broom and Prolacerta broomi Parrington are presented. New details of the braincase of Proterosuchus fergusi Broom are given as these became necessary for comparative purposes. It is suggested that the initial radiation of sauropsid reptiles was a Permian event as yet poorly documented. The phylogenetic position of Youngina forward and backward in time cannot be narrowly defined, though certain characters seem specifically to preclude it from lizard ancestry. Prolacerta, on the basis of tooth implantation, braincase morphology and postcranial anatomy is shown to be closest to the proterosuchian thecodonts. It is very definitely not concerned with lizard origins, but would on available evidence seem to be a perfectly good ancestor for the middle Triassic forms Macrocnemus and Tanystropheus which latter must cease to be regarded as lizard ancestors. We have here a rather distinct reptilian lineage which branched off from common ancestral stock just prior to the advent of archosaurs.
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    The affinities of Proterochampsa barrioneuvoi Reig
    (Bernard Price Institute for Palaeontological Research, 1975) Cruickshank, Arthur R I
    Proterochampsa barrioneuvoi Reig is re-examined and is confirmed as a proterosuchian thecodont. None of the features previously thought to ally it to the Crocodilia are solely characteristic of that group. On the other hand it is not a phytosaur nor phytosaur ancestor, only showing one real trend towards these animals in the rearward migration of the internal and external nares. Proterochampsa and its relatives Chanaresuchus, Gualosuchus and Cerritosaurus are too late in time to be phytosaur ancestors. They are grouped together in the Proterochampsidae, a family within the Proterosuchia.
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    A review of the reptile and amphibian assemblages from the Stormberg of southern Africa, with special emphasis on the footprints and the age of the Stormberg
    (Bernard Price Institute for Palaeontological Research, 1984) Olsen, Paul E.; Galton, Peter M.
    The Molteno, Elliot, and Clarens formations comprise the continental Stormberg Group of the Karoo Basin of South Africa and Lesotho. The Molteno Formation contains a well preserved macro- and microfloral assemblage but apparently no vertebrates; the Elliot and Clarens formations contain abundant vertebrates but virtually no floral remains. The vertebrate taxa represented by skeletal remains are listed and divided into two assemblages - the lower Stormberg (lower Elliot) and upper Stormberg (upper Elliot and Clarens) assemblages. The abundant, diagnosable footprint taxa are revised and their names reduced to eight genera. These ichnotaxa also fall into two biostratigraphic zones that parallel the skeletal assemblages. Comparison of the faunal assemblages with those of the European type section strongly suggests that the lower Stormberg assemblage is Late Triassic (Carnian- Norian) in age while the upper Stormberg assemblage is Early Jurassic (Hettangian-Pliens- bachian) in age. Comparisons with other continental assemblages from other areas suggest that the upper Stormberg (upper Elliot and Clarens formations) assemblage broadly correlates with the upper Newark Supergroup of eastern North America, the Glen Canyon of the southwestern United States, and the lower Lufeng Series of China- all thought to be of Early Jurassic age on the basis of floral and/or radiometric evidence. Based on these correlations, previously published paleobiogeographic maps are revised; these show a shift from Late Triassic floral and faunal provinciality to Early Jurassic homogeneity. This shift was synchronous with a widening of the equatorial arid zone.