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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Craniomandibular anatomy of the akidnognathid therocephalian Olivierosuchus parringtoni from the Early Triassic of South Africa
(Evolutionary Studies Institute, 2023) Gigliotti, Alessandro; Pusch, Luisa C; Kammerer, Christian F; Benoit, Julien; Fröbisch, Jörg
Therocephalians were an ecomorphologically varied and diverse-sized group of therapsids with widespread distribution during the late Permian and earliest Triassic periods. Here, we redescribe the holotype of the therocephalian Olivierosuchus parringtoni (BP/1/3849) from the Early Triassic Lystrosaurus declivis Assemblage Zone in the main Karoo Basin of South Africa. The specimen includes a complete skull, mandible, and the anterior portion of the skeleton. Previously unknown endocranial features are described using high-resolution computed tomography (CT), including internal surfaces of braincase and palatal bones, as well as soft tissue structures such as the brain and inner ear endocasts. Comparisons with closely related therapsids permit a detailed comparative analysis of the brain and inner ear morphology of Olivierosuchus.
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.
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.
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.
Rediscovery of the holotype of Clelandina major Broom, 1948 (Gorgonopsia: Rubidgeinae) with implications for the identity of this species
(Evolutionary Studies Institute, 2017-12) Kammerer, Christian F.
No specimen number was given for the holotype of the rubidgeine gorgonopsian species Clelandina major Broom, 1948 in its original description. Historically, a specimen in the Rubidge Collection (RC 94) was considered to represent Broom’s type specimen for C. major. However, recent study has revealed that the holotype of C. major is in fact a different specimen in the McGregor Museum in Kimberley (MMK 5031). The morphology of this specimen is consistent with the genus Clelandina, contra work based on RC 94 that considered C. major referable toAelurognathus. Clelandina major is here considered synonymous with the type species Clelandina rubidgei.MMK5031 represents only the fifth known specimen of this rare and unusual gorgonopsian.
Two unrecognised burnetiamorph specimens from historic Karoo collections
(2016-03) Kammerer, Christian F.
Two historical specimens from Permian rocks of the Karoo Basin represent previously unrecognised members of the rare therapsid group Burnetiamorpha. These specimens cannot be referred to any existing burnetiamorph species, but are left in open nomenclature because of their incompleteness (both are isolated skull roofs). The first specimen is from the Tapinocephalus Assemblage Zone (AZ) and is characterized by heavily pachyostosed supraorbital bosses and a low nasal crest. The second specimen is from the Tropidostoma AZ and is generally similar to the Malawian taxon Lende, but is unique among described burnetiamorphs in having a frontoparietal ‘dome’ that surrounds the pineal foramen. Phylogenetic analysis of burnetiamorphs recovers support for a split between Proburnetia and Burnetia-like burnetiids, here named Proburnetiinae subfam. nov. and Burnetiinae Broom, 1923.
Permo-Triassic palynology and palaeobotany of Zambia: a review
(2016-03) Barbolini, Natasha; Bamford, Marion K.; Tolan, Stephen
Permian and Triassic deposits in Zambia have been sporadically researched since the beginning of the 20th century, but there have not been many detailed works on the palaeobotany and palynology of these Karoo-aged rocks. Studies that have been published, suffered from a lack of inter-basinal correlation, which was also hampered by differing stratigraphic subdivisions. We review previous records of palynomorphs, megafloral remains and fossil wood in Zambian Permo-Triassic deposits, present a synthesis of micro- and macrofossil occurrences throughout the country, and propose a standardised subdivision for the Luangwa Valley. This will aid in future correlations between different Karoo basins and act as a framework for future palaeobotanical research in both Zambia and Gondwana.
Palaeozoic insects of southern Africa: a review
(Bernard Price Institute for Palaeontological Research, 2002) Geertsema, H; Van Dijk, D E; Van den Heever, J A
Although a substantial number of Triassic insect fossils have been discovered in southern Africa, relatively few insect fossils are known from the Permian deposits of this region. Fossil insects from the Permian period elsewhere, including the extensive entomological fauna from Eastern Europe (including Russia), Brazil and Australia is well-documented. The Irati Formation in the Parana Basin of Brazil, the temporal and lithological correlate of the Permian Whitehill Formation of South Africa, has yielded fossil insects belonging to Homoptera, N europtera, Coleoptera and Mecoptera. Fossil insects from the Whitehill Formation are usually poorly preserved and only seven specimens are mentioned in the literature. An overview is given of the more recent discoveries of Permian fossil insects in South Africa. This includes the discovery of the oldest beetle in Africa, the oldest longhorned grasshopper in the Southern Hemisphere and a survey of the Permian insects from the Beaufort Group of Natal. Reasons for the paucity of Permian insects are briefly discussed.
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, Rose
The 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.
A new record of Procynosuchus delaharpeae (Therapsida: Cynodontia) from the Upper Permian Usili Formation, Tanzania
(Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, 2009-12) Weide, D. Marie; Sidor, Christian A.; Angielczyk, Kenneth D.; Smith, Roger M.H.
Procynosuchus, the best-known Permian cynodont, has a remarkably broad geographic range, with records stretching from southern Africa to Europe. Fossils of Procynosuchus are most common in the Upper Permian Dicynodon Assemblage Zone of South Africa, but also occur in coeval East African rocks. Currently, there is one documented occurrence from the Madumabisa Mudstone Formation of Zambia, and two specimens from the Usili (=Kawinga) Formation of Tanzania. The Tanzanian specimens include a poorly preserved, incomplete skull and a partial cranium originally attributed to Parathrinaxodon proops. The latter is now considered a subjective junior synonym of Procynosuchus delaharpeae. Here we report on a new specimen collected in 2007 near the base of Kingori Mountain in Tanzania. It preserves the postorbital region of the skull and the posterior portions of both lower jaws, each containing several intact teeth. A well-preserved postcanine tooth exhibits the dental hallmarks of Procynosuchus and permits unambiguous referral to this taxon. Recent fieldwork corroborates previous suggestions that the Usili tetrapod fauna includes representatives of the Tropidostoma, Cistecephalus and Dicynodon assemblage zones of South Africa. Moreover, the presence of several endemic Usili taxa (e.g. Katumbia, Kawingasaurus, Peltobatrachus), suggests that a straightforward correlation between the Usili tetrapod fauna and a particular assemblage zone from the Beaufort Group may not be possible.

Palaeontologia africana

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