Wits Evolutionary Studies Institute (ESI)
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Item 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, FernandoTitanosuchidae 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.Item A new specimen of the sauropodomorph dinosaur Ignavusaurus rachelis from the Early Jurassic of Lesotho(Evolutionary Studies Institute, 2020-12-11) Bodenham, Ewan H; Barrett, Paul MThe upper Elliot Formation (?Rhaetian–Sinemurian) of South Africa and Lesotho has yielded a rich fauna of non-avian dinosaurs, which has generally been considered to be dominated by the massopodan sauropodomorph Massospondylus carinatus. However, re-evaluation of the abundant sauropodomorph collections from this unit suggests that the species-richness of upper Elliot sites has been underestimated. Here, we describe a series of cervical and dorsal vertebrae collected from Likhoele Mountain, Lesotho, which are referred to the rare upper Elliot sauropodomorph taxon Ignavusaurus rachelis. This material represents only the second-known specimen of this taxon, extending its geographic range, and underscores the value of undertaking detailed re-assessments of neglected historical collections.Item Postcranial osteology of the neotype specimen of Massospondylus carinatus Owen, 1854 (Dinosauria: Sauropodomorpha) from the upper Elliot formation of South Africa(Evolutionary Studies Institute, 2019-04) Barrett, Paul M.; Chapelle, Kimberley E.J.; Staunton, Casey K.; Botha, Jennifer; Choiniere, Jonah N.Massospondylus carinatus Owen, 1854, from the earliest Jurassic upper Elliot Formation of South Africa, was one of the first dinosaurs to be described from Gondwana. It has been incorporated into numerous phylogenetic, palaeobiological and biostratigraphic analyses, is often viewed as an exemplar for understanding sauropodomorph anatomy and is a key taxon in studies of early dinosaur evolution. Since its initial description, numerous specimens have been referred to this species, ranging from isolated postcranial elements to complete skeletons with three-dimensional skulls. In addition,M. carinatus has been identified in areas outside of the main Karoo Basin. Surprisingly, however, there have been few attempts to define the taxon rigorously, so that the basis for many of these referrals is weak, undermining the utility of this abundant material. Here, we provide the first detailed postcranial description of the neotype specimen ofM. carinatus, use it as a basis for diagnosing the species on the basis of cranial, axial and appendicular characters, demonstrate that it represents an adult individual on the basis of osteohistology, and discuss ways in which these data can assist in providing a better understanding of Karoo-aged African dinosaur faunas.Item 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.Item Small-bodied humans from Palau, Micronesia.(Public Library of Science, 2008-03-12) Berger, L.R.; De Klerk, B.; Quinn, R.L.; Churchill, S.E.Newly discovered fossil assemblages of small bodied Homo sapiens from Palau, Micronesia possess characters thought to be taxonomically primitive for the genus Homo. Background: Recent surface collection and test excavation in limestone caves in the the rock islands of Palau, Micronesia, has produced a sizeable sample of human skeletal remains dating roughly between 940-2890 cal ybp. Principle Findings: Preliminary analysis indicates that this material is important for two reasons. First, Individuals from the older time horizons are small in body size even relative to "pygmoid" populations from Southeast Asia and Indonesia, and thus may represent a marked case of human insular dwarfism. Second, while possessing a number of derived features that align them with Homo sapiens, the human remains from Palau also exhibit several skeletal traits that are considered to be primitive for the genus Homo. Significance. These features may be previously unrecognized developmental correlates of small body size and, if soo, they may have important implications for interpreting the taxonomic affinities of fossil specimens of Homo.Item Carnivoran remains from the Malapa hominin site, South Africa.(Public Library of Science, 2011-11-03) Kuhn, B.F.; Werdelin, L.; Hartstone-Rose, A.; Lacruz, R.S.; Berger, L.R.Recent discoveries at the new hominin-bearing deposits of Malapa, South Africa, have yielded a rich faunal assemblage associated with the newly described hominin taxon Australopithecus sediba. Dating of this deposit using U-Pb and palaeomagnetic methods has provided an age of 1.977 Ma, being one of the most accurately dated, time constrained deposits in the Plio-Pleistocene of southern Africa. To date, 81 carnivoran specimens have been identified at this site including members of the families Canidae, Viverridae, Herpestidae, Hyaenidae and Felidae. Of note is the presence of the extinct taxon Dinofelis cf. D. barlowi that may represent the last appearance date for this species. Extant large carnivores are represented by specimens of leopard (Panthera pardus) and brown hyaena (Parahyaena brunnea). Smaller carnivores are also represented, and include the genera Atilax and Genetta, as well as Vulpes cf. V. chama. Malapa may also represent the first appearance date for Felis nigripes (Black-footed cat). The geochronological age of Malapa and the associated hominin taxa and carnivoran remains provide a window of research into mammalian evolution during a relatively unknown period in South Africa and elsewhere. In particular, the fauna represented at Malapa has the potential to elucidate aspects of the evolution of Dinofelis and may help resolve competing hypotheses about faunal exchange between East and Southern Africa during the late Pliocene or early Pleistocene.Item 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, FranceThe 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.Item The affinities of the early cynodont reptile, Nanictosaurus(Bernard Price Institute for Palaeontological Research, 1990) van Heerden, Jacques; Rubidge, BruceThis 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.Item Clarification of Belemnopteris Feistmantel 1876, and description of a leaf of Belemnopteris pellvcida Pant and Choudhury 1977 found amongst a South African Ecca flora(Bernard Price Institute for Palaeontological Research, 1990) Kovacs-Endrody, EA leaf of Belemnopteris pellucida Pant and Choudhury 1977 was found for the first time in South Africa amongst an Ecca flora near Hammanskraal, about 30km north of Pretoria. The taxonomic status of Belemnopteris Feistmantel 1876 and the biostratigraphic correlation indicated by the presence of this genus is clarified.