Volume 52 2017–2018
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Item Cranial 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.Item The 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.Item Proceedings 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. BordyItem Fossil 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.Item The 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.Item Late Pleistocene vertebrate trace fossils in the Goukamma Nature Reserve, Cape South Coast, South Africa(Evolutionary Studies Institute, 2018-02) Helm, Charles W.; McCrea, Richard T.; Lockley, Martin G.; Cawthra, Hayley C.; Thesen, Guy H. H.; Mwankunda, Joshua M.More than 100 Late Pleistocene trace fossil sites have been identified in aeolianites along a 275 kilometer stretch of the Cape south coast. A zone of concentration of such sites exists within the Goukamma Nature Reserve, both along the coast and along the Goukamma River. These sites provide insight into the Pleistocene fauna along the Cape south coast. Features include lion trackways, multiple elephant tracksites, a long trackway most likely attributable to Long-horned Buffalo, medium-sized carnivore tracks, avian tracks, equid tracks attributable to the giant Cape horse, numerous artiodactyl tracks, and burrow traces. The ephemeral nature of the tracksites makes regular surveys of these areas desirable, along with site documentation and trackway replication and preservation initiatives. The protected status of the area offers opportunities for geoheritage appreciation.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 Biofilm assists recognition of avian trackways in Late Pleistocene coastal aeolianites, South Africa(Evolutionary Studies Institute, 2017-12) Helm, Charles W.; Anderson, Robert J.; Buckley, Lisa G.; Cawthra, Hayley C.; de Vynck, Jan C.Fourteen fossil avian tracksites have been identified in Late Pleistocene aeolianite deposits on the Cape south coast of SouthAfrica. One of these sites is unusual because of the preferential adherence of organic material (biofilm) to the natural cast tracks. This has enabled the recognition and identification of two ~6 m long, approximately parallel trackways that would otherwise not have been noticed. The trackways are visible from a distance of over 100 metres and contain 20 and 14 individual tracks, respectively. Up to 50 avian tracks are evident at this site. As the biofilm layer continues to thicken, the trackways become increasingly visible. Avian trackways of this length are globally rare.We propose that the biofilm adheres to sections with higher relief on a sedimentary surface, and that an understanding of this mode of preservation can be useful to more easily identify trackways in areas of comparable geological setting.Item The bony labyrinth of late Permian Biarmosuchia: palaeobiology and diversity in non-mammalian Therapsida(2017-07) Benoit, Julien; Manger, Paul R; Fernandez, Vincent; Rubidge, Bruce SBiarmosuchia, as the basalmost group of Therapsida (the stem group of mammals), are important for understanding mammalian origins and evolution. Unlike other therapsid groups, the bony labyrinth of biarmosuchians has not yet been studied, despite insightful clues that bony labyrinth morphology can provide to address palaeobiology and phylogeny of extinct animals. Here, using CT scanning, surface reconstruction and a 3D geometric-morphometric protocol of 60 semi-landmarks on the bony labyrinth of 30 therapsids (including three Mammaliaformes), it is demonstrated that bony labyrinth morphology of biarmosuchians is very distinctive compared to that of other therapsids. Despite the primitive nature of their cranial morphology, biarmosuchians display highly derived traits in the structure of the bony labyrinth. The most noticeable are the presence of a long and slender canal linking the vestibule to the fenestra vestibuli, an enlarged and dorsally expanded anterior canal, and the absence of a secondary common crus (except for one specimen), which sets them apart from other non-mammalian therapsids. These characters provide additional support for the monophyly of Biarmosuchia, the most recently recognized major therapsid subclade. Although implications of the derived morphology of the biarmosuchian bony labyrinth are discussed, definitive interpretations are dependent on the discovery of well-preserved postcranial material. It nevertheless sheds light on a previously overlooked diversity of bony labyrinth morphology in non-mammalian therapsids.Item Palynological dating and palaeoenvironments of the M1 well, Middle Miocene, Niger Delta, Nigeria(2017-07) Durugbo, Ernest Uzodimma; Olayiwola, Moshood AdegboyegaThe need to increase our knowledge of palaeo-flora is important in palaeoclimatic and palaeoenvironmental reconstruction of the Tertiary Niger Delta as to highlight possible changes in the depositional environments over time. Hence, palynological data from the M1well from the western Niger Delta region were employed in an attempt to reconstruct the Middle Miocene palaeoenvironment and palaeoclimate. The detailed palynological analysis revealed diverse and abundant palynomorph assemblages. This consisted of pollen species 60.14%, spores 25.86%, algae (Botyococcus braunii, Pediastrum sp., and Concentricytes circulus) 10.53%, miscellaneous palynomorphs (fungal elements, diatom frustules and charred Gramineae cuticle) 2.62%, dinoflagellate cysts 0.79% and acritarchs 0.06%. The well is dated Middle Miocene based on the common occurrences of diagnostic middle Miocene Niger Delta palynomorphs. Four informal palynofloral assemblage zones (MPAZ) I–IV were defined and correlated with major cycles of alternating dry and wet climatic conditions. Sediments within MPAZ I and MPAZ II were assumed to have been deposited during dominantly wet periods while MPAZ IV and III showed brief dry pulses coupled with periods of marine transgressions. The palaeoenvironment fluctuated between nearshore and marginal marine inferred from abundant records of land-derived palynomorphs and the spotty records of the dinoflagellate cysts Nematosphaeropsis labyrinthus, Nematosphaeropsis lemniscata and Impagidinium sp.