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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Subject: search.filters.subject.Beaufort Group

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Now showing 1 - 8 of 8
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    Cranial morphology of Jonkeria truculenta (Therapsida, Dinocephalia) and a taxonomic reassessment of the family Titanosuchidae
    (The Evolutionary Studies Institute, 2024-06) Jirah, Sifelani; Rubide, Bruce S; Abdala, Fernando
    Titanosuchidae are a group of herbivorous, long-snouted dinocephalians with definitive records known only from the middle Permian Tapinocephalus Assemblage Zone of the Beaufort Group (Karoo Supergroup) of South Africa. Here, the taxonomy of this family is revised; of the nine species currently recognized, only two are found to be valid: Titanosuchus ferox and Jonkeria truculenta, which can be distinguished on the basis of appendicular proportions. Jonkeria boonstrai, J. haughtoni, J. ingens, J. parva, J. rossouwi, and J. vanderbyli are synonymized with Jonkeria truculenta, and J. koupensis is considered a nomen dubium (Titanosuchidae indet.). Several new cranial features are described for J. truculenta, such as pachyostosis of the prefrontals, postorbitals and parietals, and an ontogenetic series for the species is presented.
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    Cranial morphology of Jonkeria truculenta (Titanosuchidae, Therapsida, Dinocephalia) and a taxonomic reassessment of the family
    (Evolutionary Studies Institute, 2023) Jirah, Sifelani; Rubidge, Bruce S; Abdala, Fernando
    Titanosuchidae are a group of derived herbivorous long snouted dinocephalians currently only known from the South African Karoo. Taxonomic revision of the Titanosuchids, for the first time accompanied by detailed anatomical descriptions and illustrations of representative cranial material, enabled recognition of only two species out of the nine previously recognized. These are Titanosuchus ferox and Jonkeria truculenta. Jonkeria vanderbyli, Jonkeria ingens, Jonkeria haughtoni, Jonkeria parva, Jonkeria rossouwi and Jonkeria boonstrai are here, synonymized with Jonkeria truculenta. The species Jonkeria koupensis is a nomen dubium only identified as Titanosuchid indet. Cranial characters, which modify during ontogenetic development, were, recognized for Jonkeria truculenta, and for the first time an ontogenetic growth series is, presented for this species.
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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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    A new actinopterygian fish species from the Late Permian Beaufort Group, South Africa
    (Bernard Price Institute for Palaeontological Research, 2001) Bender, Patrick
    A new genus and species of actinopterygian (ray-finned) fish, Bethesdaichthys kitchingi, is described from the Tatarian, Late Permian, Lower Beaufort Group of South Africa. Bethesdaichthys is presently known from three localities, two in the New Bethesda and one in the Victoria West districts of the Karoo region respectively. The fossils were recovered from within the Abrahamskraal Formation Tapinocephalus Assemblage Zone at the Victoria West locality, and from an uncertain Formation possibly closely equivalent to the Balfour Formation, within the Dicynodon Assemblage Zone at the New Bethesda sites. Bethesdaichthys kitchingi is a fusiform fish, up to approximately 300mm in total length, with the skull displaying a moderately oblique suspensorium, and a maxilla with a large sub-rectangular postorbital blade. Furthermore there is a complex of four suborbital bones adjacent to the orbit. The pectoral fin is large relative to body size and the tail is heterocercal with an elongate tapered dorsal body lobe. The anterior midflank scales in particular exhibit a distinctive dermal ornamentation consisting of numerous ganoine ridges. The phylogenetics and interrelationships of Bethesdaichthys kitchingiare examined. It appears to exhibit a relatively conservative morphology similar to that found in possibly related Carboniferous taxa such as the South African taxa Australichthys and Willomorichthys. Bethesdaichthys kitchingiis derived relative to stem-actinopterans such as the Howqualepis and Mimia, and also derived relative to southern African Palaeozoic actinoptyerygians such as Mentzichthys jubbi; and Namaichthys schroeden; but basal to stemneopterygians such as Australosomus, Perleldus and Saurichthys.
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    Palyno-stratigraphy of the lower Karroo sequence in the central Sebungwe District, Mid-Zambezi Basin, Rhodesia
    (Bernard Price Institute for Palaeontological Research, 1975) Falcon, Rosemary S
    Hart (1962) was the first to discuss seriously the subject "palynology-key to stratigraphy" with regard to Southern Africa. Since then a number of publications have appeared on African Karroo palynology. However, to date only one large scale microfloral zonation scheme has been proposed -that of Hart (1967). In this, four major palynofloristic zones were outlined for Lower Karroo (Permian) sequences, drawn from surface and sub-surface material in South and Central Africa. Another scheme, dividing the Permian into eight zones in S. Africa (Great Karroo Basin) , is as yet unpublished (Anderson, in press). In an attempt to apply palynology to the problems of geological correlation and relative age determinations, specifically in the field of coal exploration in Rhodesia, a standard section in the form of one borehole, the Matabola Flats borehole, well-sited, deep and with apparently continuous deposition was chosen for palynological biostratigraphic analysis. Fifty-five miospore genera and ninety-eight species have been recognised in this study. Their systematic descriptions and statistical analyses are published elsewhere, Falcon 1975 a, b. Detailed analysis of the forty-eight productive samples show large scale micro-floral changes up the stratigraphic column. Four major assemblage zones and eight assemblage sub-zones are herein proposed, thereby expanding by four the palynofloristic zones of Hart.
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    The skeleton of the Triassic anomodont Kannemeyeria wilsoni Broom
    (Bernard Price Institute for Palaeontological Research, 1975) Cruickshank, Arthur R I
    The general structure of the post-cranial skeleton of many Triassic anomodonts is now well known, but in Africa that of the stratigraphically important Lower Triassic (? Scythian) genus Kannemeyeria is known only from dissociated elements. A brief description is given for the first time of an almost complete skeleton ascribed to this genus. The environment of deposition is described briefly. The locality of the type species of the genus is also noted .
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    Permo-Triassic "lizards" from the Karroo
    (Bernard Price Institute for Palaeontological Research, 1975) Carroll, Robert L
    Three genera of sauropsid reptiles from the Permo-Triassic beds of South Africa - Saurosternon Huxley, Paliguana Broom and Palaegama Broom - were originally described as lizards, or the immediate ancestors of that group. Restudy of these forms confirms that they are close to the ancestry of later Mesozoic and Cenozoic squamates. The skull is somewhat primitive, but in size, proportions and function extremely similar to that of Kuehneosaurus. The pectoral girdle is lacertoid in the proportions and orientation of the clavicles and interclavicle; the anterior margin of the scapulocoracoid is fenestrate, and the articulating surface of the glenoid is very short. A sternum is present and one specimen shows ventral connections between the ribs and the sternum. In Saurosternon, the forelimb can be seen as very similar to that of living lizards, with special epiphyseal articulating surfaces on the proximal end of the humerus and distal end of the ulna. The pelvic girdle remains primitive, but the rear limb is close to the pattern in lizards. The fifth metatarsal is not obviously hooked, and all five distal tarsals are retained, but the proportions and functions of the ankle presage the condition in living lizards. Epidermal scales are present. Following Romer, these forms are all included in the Family Paliguanidae. They are placed in the Suborder Lacertilia, provisionally in the Infraorder Eolacertilia.
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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.