Palaeontologia africana
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ISSN (print): 0078-8554
ISSN (electronic): 2410-4418
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Item A new dicynodont (Anomodontia: Emydopoidea) from the terminal Permian of KwaZulu-Natal, South Africa(Evolutionary Studies Institute, 2019-04) Kammerer, Christian F.A new taxon of dicynodont (Thliptosaurus imperforatus gen. et sp. nov.) is described based on a dorsoventrally-crushed skull from latest Permian (upper Daptocephalus Assemblage Zone) strata in KwaZulu-Natal, South Africa. Thliptosaurus is distinguished from all other dicynodonts by an elongate intertemporal bar with broad dorsal exposure of the parietals but apparently no pineal foramen. Absence of the pineal foramen in dicynodonts is exceedingly rare; the only other taxa which exhibit this feature either have substantially broader (Kawingasaurus fossilis) or narrower (Kombuisia frerensis) intertemporal regions. Inclusion of Thliptosaurus in a phylogenetic analysis of dicynodonts recovers it as a kingoriid emydopoid, a position supported by its anteriorly-restricted pterygoid keel, elongate, curved anterior process of the lacrimal, relatively posterior position of the median pterygoid plate, and occlusion of the mandibular fenestra by a lateral plate of the dentary. Intriguingly, even in the other kingoriids which retain a pineal foramen (Dicynodontoides spp. and Kombuisia antarctica), this structure is reduced in size relative to other dicynodonts, suggesting that the pineal eye was less important for thermoregulatory activity in this clade than in other anomodonts. Although part of a local fauna including taxa that are otherwise widespread in the Karoo Basin (Daptocephalus, Lystrosaurus), the unique presence of Thliptosaurus in the relatively poorly-sampled Daptocephalus Assemblage Zone deposits of KwaZulu-Natal suggests that this region may preserve endemic taxa, and should be prioritized for future fieldwork.Item Histological evidence of trauma in tusks of southern African dicynodonts(Evolutionary Studies Institute, 2019-01) Whitney, Megan R.; Tse, Yuen Ting; Sidor, Christian A.Dicynodonts were a clade of globally-distributed therapsids known for their abundance in the fossil record and for surviving the Permo-Triassic mass extinction. The group had distinctive dental adaptations including a beak and, in many species, paired maxillary tusks. The function of these tusks has long been of interest, yet remains poorly understood.We report here on two instances of unusual morphology in tusk dentine from specimens of: 1) Lystrosaurus from the Karoo Basin of South Africa and, 2) an unidentified dicynodontoid from the Luangwa Basin of Zambia. In both, the cross-sectional shape of the tusk root is lobed and infolded, which histological features suggest is a result of abnormal dentine deposition. We infer that this abnormal morphology is likely the consequence of trauma given its reparative nature and structural similarities to trauma-related morphologies reported in the tusks of modern elephants. This study demonstrates that histological sampling of dicynodont tusks can shed light on the biology of this important clade of therapsids.Item Cranial morphology and phylogenetic analysis of Cynosaurus suppostus (Therapsida, Cynodontia) from the upper Permian of the Karoo Basin, South Africa(Evolutionary Studies Institute, 2018-03) van den Brandt, Marc; Abdala, FernandoNon-mammaliaform cynodonts are an important fossil lineage which include the ancestors of mammals and which illustrate the gradual evolution of mammalian characteristics. The earliest cynodonts (‘basal cynodonts’) are known from the late Permian. Cynosaurus suppostus is the second most abundant basal cynodont from the late Permian of the Karoo Basin of SouthAfrica, but is poorly studied, with the most recent description of this taxon being 50 years old. Since then, several important new specimens of this species have been collected, meriting a thorough description of its cranial anatomy and exploration of its interspecific variation. Here we present a comprehensive description of the cranial morphology of Cynosaurus suppostus, producing an updated diagnosis for the species and comparisons amongst basal cynodonts. Cynosaurus is identified by three autapomorphies amongst basal cynodonts: a subvertical mentum on the anterior lower jaw; a robust mandible with a relatively high horizontal ramus; and the broadest snout across the canine region, representing up to 31.74% of basal skull length. One of the new specimens described here preserves orbital scleral ossicles, structures rarely preserved in non-mammaliaform cynodonts. Cynosaurus is now only the third cynodont in which scleral ossicles have been reported.Anupdated phylogenetic analysis of basal cynodont interrelationships recovered Cynosaurus suppostus as a member of the Galesauridae in only two of 16 most parsimonious trees, providing poor support for its inclusion in that family. The majority of known Cynosaurus specimens were collected in a geographically restricted area approximately 150 kilometres in diameter. Most specimens have been recovered from the latest Permian Daptocephalus Assemblage Zone, with only two specimens known from the older Cistecephalus Assemblage Zone.Item Cretaceous faunas from Zululand and Natal, South Africa. The ammonite subgenus Hauericeras (Gardeniceras) Mastsumoto & Obata, 1955(Bernard price Institute for Palaeontologcal Research, University of the Witwatersrand, 2011-12) Kennedy, William James; Klinger, Herbert JamesFour species of the distinctive desmoceratid ammonite Hauericeras (Gardeniceras) Matsumoto & Obata, 1955, are described from KwaZulu-Natal and the Eastern Cape Province: the type species, H. (G.) gardeni (Baily, 1855), from the Santonian to Lower Campanian, H.(G.) pseudoangustum Collignon, 1961, and H. (G.) madagascariense Collignon, 1961, from the Lower Campanian, and H. (G.) rembda (Forbes, 1846) from the upper Upper Maastrichtian.Item A structural re-interpretation and revision of the type material of the glossopterid ovuliferous fruitification Scutum from South Africa(Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, 2011-12) Prevec, RoseThe Early Permian glossopterid fructification Scutum, described by Edna Plumstead in the 1950s from the Vereeniging locality in the Karoo Basin of South Africa, was one of the first glossopterid seed-bearing organs to be found in organic attachment to Glossopteris leaves. Examination of the type material necessitated a revision of this plant fossil genus and a re-evaluation of described South African species. Key characteristics of the genus are the broad and prominent wing, and a low receptacle length to width ratio (<2:1). Specimens of South African Scutum are currently attributed to three species, from two localities, but display intergrading morphological features that can be reasonably accommodated within a single species, S. leslii. Three-dimensional interpretation and reconstruction of impression fossils of Scutum fructifications preserved in attachment to Glossopteris leaves confirms that the seed-bearing surface of the receptacle faces the adaxial surface of the subtending leaf. The nature of the seed scars on the receptacle and their relationship to the peripheral wing of the fructifications is clarified.Item Massospondylus carinatus Owen 1854 (Dinosauria: Sauropodomorpha) from the Lower Jurassic of South Africa: Proposed conservation of the usage by designation of a neotype(Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, 2010-12) Yates, Adam M.; Barrett, Paul M.The purpose of this article is to preserve the usage of the binomen Massospondylus carinatus by designating a neotype specimen. Massospondylus is the most abundant basal sauropodomorph dinosaur from the Early Jurassic strata of southern Africa. This taxon forms the basis for an extensive palaeobiological literature and is the eponym of Massospondylidae and the nominal taxon of a biostratigraphical unit in current usage, the ‘Massospondylus Range Zone’. The syntype series of M. carinatus (five disarticulated and broken vertebrae) was destroyed during World War II, but plaster casts and illustrations of the material survive. Nonetheless, these materials cannot act as type material for this taxon under the rules of the ICZN Code. In order to avoid nomenclatural instability, we hereby designate BP/1/4934 (a skull and largely complete postcranial skeleton) as the neotype of Massospondylus carinatus.Item Fluctuations in Miocene climate and sea levels along the southwestern South African coast: inferences from biogeochemistry, palynology and sedimentology(Evolutionary Studies Institute, University of the Witwatersrand, 2013-12-18) Sciscio, Lara; Neumann, Frank H.; Roberts, Dave; Tsikos, Harilaos; Scott, Louis; Bamford, MarionThe largest deposit of excellently preserved Mio-Pliocene vertebrate faunas in South Africa is located at the well known Langebaanweg (LBW) site along South Africa’s west coast in the southwestern Cape. This research deals with a core (BH2) drilled at Langebaanweg ‘E’ Quarry, which captures Miocene fluvial deposits that unconformably underlie the Mio-Pliocene deposits. The aim of the study is to constrain fluctuations in climate and ecosystems in the region during the Miocene, using a combination of sedimentology, palynology, and biogeochemistry. The latter is a novel application and includes bulk C and N isotope measurements as well as branched GDGT (glycerol dialkyl glycerol tetraether) membrane lipid compositions of the organic fraction of the core. The mean annual temperature (MAT) at time of deposition and ambient pH values were calculated using the Methylation index of Branched Tetraethers (MBT) and Cyclization ratio of Branched Tetraethers (CBT) proxies. The core samples analysed spanned a depth interval of 17–33 m and had MATs ranging between 12.4°C and 26.6°C and pH range from 4.4 to 6.4. Furthermore, samples showed a low variance and light d13C distribution (from –25.52‰ to –24.27‰) and overall low C/N ratios. Palynological investigation supplemented earlier similar studies, reaffirming alternating sequences of tropical and subtropical elements including wetland taxa and complementing calculated MAT results. Pollen results from the lowermost subsection indicated a species-rich tropical/subtropical Podocarpus dominated forest with MATs at 16.2°C. The pollen-bearing middle subsection shows initially subhumid conditions, with MATs between 15.4 and 26.6°C, similar to the bottom of the section with high Podocarpaceae percentages, low Restionaceae and aquatics. Above this, local taxa, e.g. Restionaceae and algae increase, and a marine influence is indicated by abundant dinoflagellates. The uppermost subsection from a depth of 7.20–7.60 m shows similar conditions (with little marine influence) to that of the lower part of the middle subsection II. Biochemical and sedimentological data are not available for the uppermost subsection. The results suggest that regional Miocene climate showed high amplitude fluctuations (possibly driven by orbital forcing as seen in marine cores), underscoring the potential of biogeochemistry for unravelling past climates and ecosystems.Item Cretaceous faunas from Zululand and Natal, South Africa. Texasia cricki Spath, 1921 (Cephalopoda: Ammonoidea) an early Santonian marker fossil from the Mzamba Formation of the Eastern Cape Province(Evolutionary Studies Institute, University of the Witwatersrand, 2013-12-18) Kennedy, William James; Klinger, Herbert ChristianThe type material of ‘Gen. nov. (Muniericeras?)’ cricki Spath, 1921, from the Santonian part of the Mzamba Formation , Eastern Cape Province, is revised, and referred to Texasia Reeside, 1932, of which Lehmaniceras Collignon, 1966 is a subjective junior synonym. Lehmaniceras sornayi, L. acutum, L. macer, L. pingue, L. ultimum and possibly L. gracile of Collignon, 1966, originally described from Madagascar, are further synonyms, as is Barroisiceras umzambiensis van Hoepen, 1968, which is based on a single specimen from Mzamba. The species occurs in the lower part of the Zone of Texanites hourcqi in Madagascar, confirmed here as lower, rather than middle, Santonian.Item 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, FernandoTapinocephalid 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.Item Cretaceous faunas from Zululand and Natal, South Africa. The ammonite genus Codazziceras Etayo-Serna, 1979(2012-12) Kennedy, William James; Klinger, Herbert ChristianA new species of the Coniacian ammonite genus Codazziceras Etayo-Serna, 1979, previously known with certainty only from Colombia, is described from the St Lucia Formation of northern KwaZulu-Natal.