The postcranium of the carnivorous cynodont Chiniquodon from the Middle Triassic of Namibia and the palaeo-environment of the Upper Omingonde Formation

A Dissertation submitted to the Faculty of Science, University of the Witwatersrand, in fulfilment of the requirements for the Degree of Master of Science Johannesburg, 2015The Chiniquodontidae is a family of Triassic carnivorous cynodonts well represented in the Middle-Upper Triassic of Argentina and Brazil. Chiniquodontids were more recently discovered in Madagascar and central Namibia, representing the only record of the family outside South America. The Namibian specimen was discovered in the Upper Omingonde Formation and is represented by the skull and a partial skeleton. The new chiniquodontid was identified as Chiniquodon and is diagnosed by the postcranial characteristics identified; a strong bend in the proximal portion of thoracic ribs, reduced curvature of the clavicle, although this may be due to deformation, robustness of the neck of the ilium, differences in the angulation between the edge of the posterior lamina of the ilium and the margin of the neck, and a large ischium, which is more than twice the size of the pubic plate. The postcranial material of the chiniquodontid from Namibia is described and compared with that of South American chiniquodontids. Chiniquodontids lack costal plates on ribs, show a tall and slender scapular blade, a large acromion process positioned well above the scapular neck and absence of disc-like phalanges in the autopodium. The Namibian Chiniquodon provides the first evidence of elements from the pes in chiniquodontids, and one of the few for non-mammaliaform cynodonts. Sedimentological studies confirm that the Upper Omingonde Formation of Namibia represents fluvial deposits of braided and meandering rivers formed in a predominately arid climatic regime during the Middle Triassic

Pleistocene large mammal bone breccia in calc-tufa, northern Kaokoland, Kunene Region, Namibia

International audienceOn account of the abundant plant, invertebrate and vertebrate fossils that they contain, the cascade tufa occurrences of the Kunene Region, Namibia, comprise an important source of information about past climates of the late Tertiary and Quaternary. Most of the vertebrate fossils thus far encountered in the tufas consist of microfauna, the remains of medium and large mammals being sporadic and rare. The discovery of a rich concentration of large mammal skeletal remains at Ozombindi, northern Kaokoland, is unusual, in that there are few if any small mammals associated with the bonebearing lenses, which consist of vast quantities of fossil limb bones and jaws of zebras, large bovids, hyaenids and possibly rhinocerotids. The Ozombindi occurrence is interpreted to represent a natural trap that formed in cascade tufas during the early Pleistocene, into which animals fell but were unable to get out. Skeletal remains of many hundreds of individuals are preserved in an inextricable jumble of bones piled one upon the other in three dimensions. The aim of this article is to put on record the presence of the Ozombindi bone breccia, and to provide preliminary estimates as to its age and palaeoclimatic significance. Taphonomic studies will throw much light on the formation of this unique (for Namibia) concentration of fossil bones

New information about African late middle Miocene to latest Miocene (13-5.5 Ma) Hominoidea

International audienceIn Africa, relatively few hominoid fossils are known from the late middle Miocene and late Miocene periods corresponding to the time span 13-5.5 million years ago, compared to the preceding and subsequent periods from which several thousand specimens have been reported from many different localities. In Eurasia, in contrast, many hominoid fossils are known from the Late Miocene period from diverse localities scattered from Spain in the west to China in the East. The scarcity of hominoid fossils from this period in Africa lent support to the hypothesis that the ancestors of extant African Apes and hominids may have evolved in Eurasia and then dispersed to Africa during the late Miocene where they gave rise to the extant Gorilla, Pan and Homo lineages.We herein document additional hominoid fossils from Berg Aukas, Namibia, aged ca 12-13 Ma, and rectify the locality data concerning the Niger proto-chimpanzee fossil. The new data indicate that Africa was not devoid of hominoids during the period under discussion, and they support the hypothesis that the extant African Apes and hominids may have evolved autochthonously within the continent

Southern African Tetraconodontinae: recent discoveries;

International audienceTetraconodont suids are in general rather poorly represented in Southern Africa, except at Langebaanweg, Cape Province and the Chiwondo Beds, Malawi. We here describe material from two localities in Namibia and one in South Africa in order to fill out the fossil record of this subfamily of artiodactyls in the subcontinent. The oldest specimens (Nyanzachoerus sp. cf jaegeri) are from Kaukausib Fontein, Namibia (ca 4-6 Ma), the next oldest (Gerontochoerus koobiforaensis) are from Brad Pit 'A', Bolt's Farm, South Africa (ca 3.7 Ma) and the youngest (Gerontochoerus scotti) are from Ekuma Rhino Site, northern Namibia (ca 3.2 Ma)