Volume 52 2017–2018
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- ItemCranial 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.
- ItemThe remedial conservation and support jacketing of the Massospondylus carinatus neotype(Evolutionary Studies Institute, 2018-03) Graham, Mark R.; Choiniere, Jonah N.; Jirah, Sifelani; Barrett, Paul M.Massopondylus carinatus Owen, 1854 is a non-sauropodan sauropodomorph (‘prosauropod’) dinosaur whose remains are abundant in the Upper Karoo Supergroup sediments of southern Africa (e.g. Owen 1854; Seeley 1895; Cooper 1981; Gow 1990; Gow et al. 1990; Sues et al. 2004; Barrett & Yates 2006; Reisz et al. 2005). It occurs at numerous localities in the Upper Elliot and Clarens formations of South Africa and Lesotho, as well as in the Forest Sandstone Formation of Zimbabwe (Haughton 1924; Cooper 1981; Kitching&Raath 1984). Several almost complete skeletons are known, including skulls, and as a result Massospondylus has featured heavily in discussions of early dinosaur ecology, phylogeny and palaeobiology (e.g. Cooper 1981; Barrett 2000; Zelenitsky & Modesto 2002; Reisz et al. 2005, 2012; Apaldetti et al. 2011, among many others). However, the original syntype series of Massospondylus carinatus was destroyed duringWorldWar II and shown to be taxonomically indeterminate, undermining the nomenclatural stability of this important taxon (Sues et al. 2004; Yates & Barrett 2010). In order to rectify this problem, a complete skeleton representing an adult individual, BP/1/4934 (nicknamed ‘Big Momma’), was designated as the neotype (Yates & Barrett 2010). BP/1/4934 was collected from the Upper Elliot Formation of Bormansdrift Farm, in the Clocholan District of the Free State, by Lucas Huma and James Kitching in 1980 (see Kitching & Raath 1984, for locality details). This farm is also the type locality of the early turtle Australochelys (Gaffney and Kitching, 1994) and has yielded other Upper Elliot formation tetrapod material including the cynodont Pachygenelus and other sauropodomorph remains (Kitching&Raath 1984). BP/1/4934 is the most complete specimen of a non-sauropodan sauropodomorph dinosaur known from the entire African continent and is therefore of major regional and international significance. In addition, since 1990 it has formed part of a permanent public exhibit showcasing African palaeontological discoveries in the J. W. Kitching Gallery of the Evolutionary Studies Institute (ESI) of the University of the Witwatersrand. During recent research work on BP/1/4934, as part of an on-going collaboration on early dinosaurs between the ESI and Natural History Museum, London (NHMUK), it was noted that its condition had deteriorated and that urgent remedial conservation work was required in order to preserve it for future generations. As a result, the specimen was temporarily removed from public display to facilitate this work, which is described in detail below (see also Graham 2017). The primary purpose of the conservation project was to assess the condition of the specimen, undertake conservation in order to stabilise it and to manufacture ‘clam-shell’ type support mounts/jackets for each of the blocks to enable the specimen to be displayed in an articulated posture within a purpose-built display case. An important consideration was that the blocks should be readily accessible from both left and right sides to researchers whilst securing the fossil safely. Finally, this project also provided an opportunity to facilitate knowledge exchange between the conservation staff at the ESI and NHMUK, in order to share and extend technical expertise.
- ItemProceedings of the 2nd International Conference of Continental Ichnology (ICCI 2017), Nuy Valley (Western Cape Winelands), 1–8 October 2017(Evolutionary Studies Institute, 2018) Bordy, Emese MThe 2nd International Conference of Continental Ichnology (ICCI 2017) was held in Nuy Valley (Western CapeWinelands) and followed by a field trip across South Africa to Lesotho from 1st to 8th of October 2017. The conference was dedicated to the study of continental trace fossils, and delegates presented research that focused on investigating various ichnofossils such as burrows, nests, tracks and trails. These are important not only for detailed characterization of past depositional environments, recognition of unconformities, prospecting for hydrocarbon resources, and biostratigraphic subdivisions, but also for the direct link they provide to ancient animal behaviour. The conference was organized by Dr Emese M. Bordy and the postgraduate students of her Sedimentology–Palaeontology Group at University of Cape Town (UCT), and was attended by 50 international delegates from Canada, U.S.A., Uruguay, Argentina, France, Germany, Sweden, Switzerland, Russia, Spain, U.K., Italy, Poland, South Africa and Lesotho (Fig. 1). This proceedings volume reflects the calibre and experience of the ICCI 2017 attendees, who appeared to be an ideal mix of senior and junior scientists. One third of the delegates were postgraduate students, and about of quarter of them were international students. We hope that all of you will enjoy the scientific content of this proceedings volume, which, among others, aims to showcase some of the best continental ichnological work globally and demonstrate why southern Africa is not only an exquisite geological and palaeontological wonder but also a world class ichnological research destination. The abundance and often uniqueness of the continental trace fossils in southern Africa are in stark contrast with the slow and punctuated development of ichnology in the region, even though the recognition and utilization of animal traces have been actively practiced here since prehistoric times. Cave paintings from the pre-1800s indicate that the indigenous hunter-gatherer San people, who have legendary neoichnological expertise, developed an early interest in the rich palaeoichnological record of the region and attempted to interpret ancient trace-making organisms (Ellenberger et al. 2005). Fascination with trace fossils and the identification of the producers by layman have also been recorded, among others, in the Western Cape (South Africa), where local farmers interpreted some Ordovician eurypterid tracks as footprints of ancient tortoises (Fig. 2A – Braddy & Almond 1999). The incorrect identification of trace fossils, which seems to be one of the most persistent traits of ichnology, is also associated with the first written record of a southern African trace fossil (later named Plagiogmus, a vermiformmetazoan trace – Fig. 2B) originally reported as impressions of fossil eels by H. Lichtenstein in his diary in 1803 (Macrae 1999; Master 2010). The first published record of invertebrate ichnofossils appeared in press nearly 70 years later as ‘trails of worms and tracks of Crustacea’ found in the Permian Ecca Group on Schietfontein farm (near Carnarvon) (Dunn 1872). Although vertebrate tracks were recorded in southern Africa in the late 19th century (?Dicynodon tracks in South Africa by Holub 1881; bird or lizard trackways in Lesotho by Dieterlen 1885 and Christol 1897), the first mention of invertebrate ichnofossils (Spirophyton) as fairly reliable stratigraphic markers has only been published in southern Africa in the early 20th century (Rogers 1905), after the ‘Age of Fucoids’ and well into the ‘Period of Reaction’ in European history of trace fossil studies. In these early days, Spirophyton was attributed to fucoids (remains of marine algae) or inorganic processes (Rogers 1905; Hatch & Corstorphine 1905) and impressions of seaweed of screw-like form(Schwarz 1912). Its first acceptable interpretation was given almost half of a century later as fossil traces of burrowing worms (Du Toit 1954). Following a slow start, ichnology in southern Africa only developed into an established discipline that links geology, sedimentology and palaeontology during the early 1970s and 1980s. This period is marked by the publication of the first detailed ichnofossil descriptions, ichnotaxonomic treatments and ichnologically based biostratigraphic and palaeoecological reconstructions. This golden era of southern African ichnology is primarily featured in internationally acclaimed contributions by Ann Anderson (Palaeozoic invertebrate ichnofossils, South Africa), Paul Ellenberger (Mesozoic vertebrate tracks, Lesotho), and Gerald Germs (Precambrian and Cambrian invertebrate ichnofossils, Namibia and South Africa). These active years also led to pioneering application of ichnofossils (in conjunction with lithofacies assemblages) to sedimentary facies analysis and interpretation (e.g. palaeobathymetry, marine vs non-marine settings) and incorporation of neoichnological studies in trace fossil interpretations (see works by D.K. Hobday, T.R. Mason, R. Shone, R.M.H. Smith, I.G. Stanistreet, I. Rust, B.R. Turner). The sluggish progress of ichnology in southern Africa, possibly due to geoscientific preoccupation with Karoo vertebrates and economically important Archaean rocks (Mason 1985), appears to be transformed by renewed interest in ichnological research in recent decades. We trust that the transformation has been spurred on by ICCI 2017, which injected even more rigour and enthusiasm into our local research community and offered all attendees opportunities to share and exchange ideas and to foster networking among potential collaborators. Once again, enjoy reading this proceedings volume of Palaeontologia africana! On behalf of the organizing committee: Emese M. Bordy
- ItemFossil trees from the basal Triassic Lebung Group at the Makgaba site, west of Mokubilo, Botswana(Evolutionary Studies Institute, 2018-03) de Wit, Michael; Bamford, Marion; van Waarden, CFossil wood samples were collected from an area underlain by Karoo Supergroup rocks along the southern edge of Sua Pan in east central Botswana. From the local stratigraphy it suggests that these fossils have been derived from the Mosu sandstones that occurs at the base of the Mosolotsane Formation and which is time-equivalent to the Molteno Formation in South Africa that is of Triassic age. Based on the arrangement of tracheid pits the fossil wood has been identified as Agathoxylon, and most likely Agathoxylon africanum. This species has a Permian to Triassic time range in southern Africa and probably is the first published record of Agathoxylon africanum in Botswana.
- ItemThe first skeletal evidence of a dicynodont from the lower Elliot Formation of South Africa(Evolutionary Studies Institute, 2018) Kammerer, Christian F.Historical fossil specimens from the lower Elliot Formation are identified as representing a large-bodied dicynodont, the first known from skeletal material in the Late Triassic of South Africa. Although fragmentary, these fossils differ from all other known Triassic dicynodonts and are here described as a new taxon, Pentasaurus goggai gen. et sp. nov. Pentasaurus can be distinguished from other Triassic dicynodonts by a number of mandibular characters, most importantly the well-developed, unusually anteriorly-positioned lateral dentary shelf. Phylogenetic analysis indicates that Pentasaurus is a placeriine stahleckeriid. Placeriines include the latestsurviving dicynodonts but their remains are primarily known from the Northern Hemisphere, with their only previously-known Southern Hemisphere representative being the Middle Triassic Zambian taxon Zambiasaurus. The discovery of a placeriine in the Late Triassic of SouthAfrica supports recent proposals that local climatic conditions, not broad-scale biogeographic patterns, best explain the observed distribution of Triassic tetrapods. The tetrapod fauna of the lower Elliot Formation is highly unusual among Triassic assemblages in combining ‘relictual’ taxa like dicynodonts and gomphodont cynodonts with abundant, diverse sauropodomorph dinosaurs.
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