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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A brief history of Massospondylus: its discovery, historical taxonomy and redescription of the original syntype series
(The Evolutionary Studies Institute, 2024-12) Barrett, Paul M; Chapelle, Kimberley EJ
Massospondylus carinatus Owen, 1854 is one of the first dinosaurs to have been described from outside Europe and was based on material collected from what is now the upper Elliot Formation of the Free State province, South Africa. The species was included in various taxonomic reviews during the late nineteenth and early twentieth centuries but no additional material was referred beyond the original syntype series and it remained poorly known. This was exacerbated by the destruction of the syntypes during World War II. From the 1970s onward, fieldwork in the upper Stormberg Group of South Africa, Lesotho and Zimbabwe led to the discovery of many new sauropodomorph dinosaur specimens that have been referred to the taxon (often uncritically) that have been used to shed further light on the anatomy, palaeobiology and biostratigraphical utility of Massospondylus carinatus. Here, we review the taxonomic history of this species, provide updated descriptions of the syntypes (based on surviving casts) and use apomorphies to identify these specimens more accurately.
A new middle Permian burnetiamorph (Therapsida: Biarmosuchia) from the South African Karoo filling a gap in the biarmosuchian record
(The Evolutionary Studies Institute, 2024-09) Matlhaga, Fonda; Benoit, Julien; Rubidge, Bruce S
Biarmosuchia, the most basal therapsid clade, is represented by relatively few specimens known from Permian deposits in Russia and southern Africa. In both the Guadalupian (middle Permian) and Lopingian (late Permian), biarmosuchians represent less than 1% of the fossil record at the specimen level. Here, we describe a new burnetiamorph biarmosuchian, Impumlophantsi boonstrai, based on a partial skull and associated postcrania from the upper Tapinocephalus Assemblage Zone. It is characterized by the presence of a low nasal crest with a unique morphology among burnetiamorphs. Inclusion of this taxon in an updated phylogenetic analysis of biarmosuchians indicates that this specimen is one of the most basal burnetiamorphs, representing the only record of this grade from the middle Permian.
A Tribute to Professor Bruce Sidney Rubidge
(2023-07) Hancox, P. John; Day, Michael O.
Professor Bruce Sidney Rubidge has published hundreds of articles and papers covering various aspects of the geology of the Cape and Karoo supergroups and their palaeontological signatures. His work has significantly advanced our understanding of numerous taxonomic groups, as well as the litho- and biostratigraphy of the Karoo Supergroup. He has also driven the robust radiometric dating of the lower half of the Karoo Supergroup, and via supervision and collaboration with postgraduate students, our understanding of the basin fill and the end-Guadalupian extinction in South Africa. Bruce has also supervised numerous honours, masters and doctoral students (Fig. 1) and provided strong research leadership to many South African and international collaborators. Bruce’s vision and dedication to first the Bernard Price Institute for Palaeontological Research (BPI) and now the Evolutionary Studies Institute (ESI) have guided it to become the connected 21st century establishment that it is today.
The advent of herbivory in certain reptilian lineages during the Triassic
(Bernard Price Institute for Palaeontological Research, 1978) Gow, C. E.
The dentitions of several presumed herbivorous Triassic reptiles are described and discussed. Some changes in dentitions with growth suggest that juveniles were insectivorous. The appearance of these forms may have been facilitated by floral changes which took place in the early Triassic.
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.
The affinities of the early cynodont reptile, Nanictosaurus
(Bernard Price Institute for Palaeontological Research, 1990) van Heerden, Jacques; Rubidge, Bruce
This investigation into the anatomy of the four extant specimens of Nanictosaurus has revealed that there is one valid species, viz. N. kitchingi Broom 1936 which has two junior synonyms, viz. N. robustus Broom 1940 and N. rubidgei Broom 1940. The closest known relative of Nanictosaurus is the well-known cynodont Thrinaxodon liorhinus. The differences from Thrinaxodon and other early cynodonts are discussed and illustrated.
African chelonians from the Jurassic to the present: phases of development and preliminary catalogue of the fossil record
(Bernard Price Institute for Palaeontological Research, 2000) de Lapparent de Broin, France
The five major phases in the palaeontological history of African chelonians are presented: 1) autochthonous development of the north Gondwanan pleurodires from a Pangean source group; 2) littoral expansion of a member of this group (Bothremydidae), accompanied by the arrival of Laurasian marine turtles; 3) in situ development of pleurodires and the immigration of Eurasian cryptodires (Oligo-Miocene) traversing the Tethys in several waves; 4) great diversification and endemism (Pliocene to Holocene); 5) important faunal reduction due to climatic changes at the end of Holocene times (cooling, aridification); elsewhere, great speciation and arrival during the Present of the last European immigrant in the north. Throughout the period under consideration there were several reductions in taxonomic diversity and emigrations from Africa. A preliminary catalogue of the fossil record of African chelonians is given, presented country by country followed by a taxonomic listing.
African fossil Lissamphibia
(Bernard Price Institute for Palaeontological Research, 1995) van Dijk, D. E.
The Anura (Frogs and Toads) are represented in Africa and associated regions by fossils of every epoch from the Cretaceous to the Holocene. Pipid frogs of African affinity are known from the Early Cretaceous of Israel and Later Cretaceous of South America and Africa; those of Israel and South America have been well-studied, but only one from Africa has been: Eoxenopoides reuningi from Namaqualand. Two well-studied Palaeocene frogs of South America, Shelania pascuali and Xenopus romeri, have affinities with the African pipids. Apart from a Miocene assemblage from North Africa (including pipids, which are now exclusively sub-Saharan) and one species from Namibia, Xenopus stromeri, the fossil African anurans remain largely unstudied. Deposits in which the African anuran fossils occur represent crater lakes, other lacustrine deposits, including lacustrine tuffs, river terraces, deltas, estuarine/lagoon zones, karst landscapes and archaeological sites; data are not available for several of the recorded fossils. No fossils in Africa appear to have been definitely ascribed to the Urodela or Caecilia.
An aggregation of juvenile Youngina from the Beaufort Group, Karoo Basin, South Africa
(Bernard Price Institute for Palaeontological Research, 1995) Smith, Roger M. H.; Susan, E. Evans
An assemblage of five fully-articulated juvenile skeletons of Youngina has been recovered from the Late Permian strata of the south-western Karoo Basin. These 12-cm-long skeletons are not only the first articulated juveniles of this taxon, but also the oldest yet found in the Karoo Basin. They are preserved in overbank mudrocks of the Hoedemaker Member (Beaufort Group, Adelaide Subgroup) on the farm Leeukloof 43 in the Beaufort West district. Although they are estimated to be some three million years older than previously described Youngina, these specimens show no significant skeletal differences. The high degree of articulation and the spatial arrangement of these skeletons in a dish-shaped hollow is compelling evidence for them having huddled together within an underground burrow. Taphonomic analysis of associated fossils indicates that this was probably a mechanism to reduce water loss during drought on the ancient Karoo floodplains .
Allometric growth in the Diademodontinae (Reptilia; Therapsida); a preliminary report
(Bernard Price Institute for Palaeontological Research, 1978) Grine, F. E.; Hahn, B. D.
The hypothesis that many, if not all, of the South African and Zambian specimens, which have been regarded as different diademodontine genera and species, actually consitute a taxonomically homogeneous, ontogenetic growth series is tested. The principles of allometric growth were applied to this sample of fossils, which varied considerably in size and shape. The approach which was followed was exclusively morphometric. The results indicate that these specimens do represent various ontogenetic stages of a growth series of only a single species of Diademodon Seeley.
The ammonite genus Diaziceras Spath, 1921, from the Campanian of KwaZulu-Natal, South Africa, and Madagascar
(2012-12) Kennedy, William James; Klinger, Herbert Christian
The ammonite genus Diaziceras Spath, 1921, and the type species, D. tissotiaeforme are revised and referred to the subfamily Lenticeratinae Hyatt, 1900, of the family Sphenodiscidae Hyatt, 1900. Skoumalia Summesberger, 1979, is interpreted as a junior synonym of Diaziceras. Diaziceras guillantoni Hourcq, 1949, and D. spathi Hourcq, 1949, are regarded as synonyms of D. tissotiaeforme, and all are referred to the Lower Campanian on the basis of records from Madagascar.
Ammonites from offshore deposits near Bogenfels, Namibia
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Klinger, Herbert Christian; McMillan, Ian K.
Pyritized ammonite nuclei and fragments were recovered by vibracore sampling from offshore deposits near Bogenfels, Namibia. Although these could only be identified at genus level, the association of Baculites and Scaphites suggest a Coniacian age for these deposits which conforms with the age of the associated foraminifera.
Anatomy and phylogenetic relationships of a possible lessemsaurid with associated plant fossils from the lower part of the Elliot Formation
(Evolutionary Studies Institute, 2023) Moopen, Atashni; Matiwane, Aviwe; Viglietti, Pia A; Choiniere, Jonah N
The Elliot Formation forms the middle layer of the Stormberg Group of South Africa and ranges in age from the Upper Triassic to the Lower Jurassic. This stratigraphic unit bears a rich and varied faunal assemblage, including a wide variety of vertebrate fossils, the most abundant of which are sauropodomorph dinosaurs. While Early Jurassic sauropodomorphs are increasingly well-known, our knowledge of Late Triassic sauropodomorphs from the lower Elliot Formation is still at a deficit. Specimens from this section of the Stormberg Group can provide key information on the early evolution of Sauropodomorpha. Here we report on a new specimen of a Late Triassic sauropodomorph from a locality a short distance above the Molteno – Elliot boundary making it among the stratigraphically lowest sauropodomorphs from South Africa. Phylogenetic analyses and body mass estimations indicate the specimen represents a medium-to-large-bodied possible lessemsaurid with a combination of plesiomorphic and derived characters. This specimen adds to the diversity of the lower Elliot Formation and provides stronger support for a biogeographical link between the Elliot Formation and the Los Colorados Formation of Argentina. This skeletally immature possible lessemsaurid also provides insight into body size evolution during the Norian, a critical time for the evolution of sauropodomorph gigantism. The fossil plant genera Taeniopteris and Cladophlebis were recovered from sediments containing the sauropodomorph specimen, documenting one of the first co-occurrences of dinosaurs and plant material in the Elliot Formation, as well as preserving direct evidence of plant-insect interactions.
The anterior of the palate in Euparkeria
(Bernard Price Institute for Palaeontological Research, 1970) Gow, C. E.
Ewer (1965) has given a careful and comprehensive description of the anatomy of the thecodont Euparkeria, but erred if anything on the side of caution in her preparation of the material. This is a commendable approach, but it has meant that certain details remained unknown. Recently Cruickshank (1970) has redescribed and reinterpreted the braincase as being surprisingly primitive. The present author's current interest lies in the origin of the lizards, and this necessarily implies an interest in Archosaur origins. In this regard an important element of the skull is the vomer; this will become apparent when recently completed work on the Millerosauria is published (Gow 1971). The important feature is the nature and disposition of vomerine teeth. Not surprisingly the vomer is not known in detail in any "Eosuchian" or early lepidosaur, as it usually lies hidden by the symphysis of the lower jaws and in any event requires delicate preparation.
THE ANTERIOR OF THE PALATE IN EUPARKERIA
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 1970) Gow, C. E.
In view of the central position of Euparkeria in the accepted phylogeny of the Archosaurs it was considered necessary to examine the vomer, and to this end one of the skull blocks listed by Ewer (SAM 6050) was prepared in formic acid. This yielded in addition to the vomers, important new information on the internal structure of the maxillae. The vomer stresses the primitive nature of the animal while the structure of the maxilla considerably strengthens its affinities with later archosaurs.
An articulated skeleton of a small individual of Diademodon (Therapsida; Cynodontia)
(Bernard Price Institute for Palaeontological Research, 1979) Gow, C. E.; Grine, F. E.;
This paper records a nearly complete, articulated skeleton of Diademodan in undoubted association with a skull of that animal. Previously, only portions of postcranial skeleton have been found in association with cranial remains of this genus. The skeleton is that of a relatively small (ontogenetically young) individual. Skeletal proportions are tabulated, rib and vertebral differentiation is described and discussed. Diademodon is shown to have had a long tail.
Aspects of palynology in Rhodesia
(Bernard Price Institute for Palaeontological Research, 1978) Falcon, Rosemary M. S.
This paper is based on a Doctoral Thesis presented to the University of the Witwatersrand, which in whole or part will be published elsewhere at greater length. The essence of the research is presented in three text figures which show the proposed correlations of Karoo strata on opposite sides of the Rhodesian palaeowatershed, correlations with Karoo-equivalent strata in other parts of Gondwanaland, and palaeofloristic trends in Rhodesia during the Permo-Triassic.
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.
Assessing the biology of fossil vertebrates through bone histology
(Bernard Price Institute for Palaeontological Research, 1997) Chinsamy, Anusuya
Soon after death and burial of an animal, the organic components of bone generally decay. The closely associated inorganic components (mainly apatite) are more resilient and even after millions of years of burial, preserve the spatial organisation of the collagen fibres and hence the structure of the bone. In the past fossil bone histology has been the subject of substantial research. Such studies have included a wide array of extinct vertebrates including fishes, amphibians, pelycosaurs, therapsids, ichthyosaurs, pterosaurs, and dinosaurs. The relative rate ofbone formation is indicated by the texture of the fibrillar matrix, while the overall nature of the primary compact bone provides a direct assessment of whether bone deposition was continuous or interrupted. The amount of secondary bone formation depicts the extent of primary bone resorption and subsequent redeposition. In addition, the internal organisation of bone indicates remodelling and relocation processes of growth, including functional adaptations of the bone morphology. Thus, osteohistology reflects ontogeny, growth dynamics, biomechanical adaptations, as well as various events that punctuate the life history of an animal.
Atmospheric carbon dioxide/oxygen imbalance in the late Cretaceous, hatching of eggs and the extinction of biota
(Bernard Price Institute for Palaeontological Research, 1978) Oelofsen, B. W.
A new theory explains why dinosaurs, pterosaurs and large avian species like Hesperornis became extinct at the end of the Cretaceous while mammals, smaller Cretaceous birds, crocodiles, chelonians and saurians survived . An atmospheric carbon dioxide/oxygen imbalance at the end of the Cretaceous caused by kimberlite volcanism, basalt flows and a reduction in oxygen production by marine phytoplankton is proposed. The unfavourable area to volume ratio of large eggs for diffusion of respiratory gases compared to that of small eggs resulted in the asphyxiation of the embryos of large endothermic egg laying groups. Endothermic species, e.g. dinosaurs that covered their eggs with soil, restricted the free circulation of air and would have been first to become extinct. Smaller ectothermic species, e.g. crocodiles, chelonians and saurians with lower embryonic respiratory requirements and endothermic species like the birds that did not cover their eggs, survived.

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