Volume 42 May 2007
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Item Morphological trends in the molars of fossil rodents from the Fayum Depression, Egypt(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Lewis, Patrick J.; Simons, Elwyn L.While many of the mammalian taxa from the Fayum of Egypt, such as the primates and hyraxes, have been well-studied, little is known about the rodents. Species described to date have all been referred to the endemic family Phiomyidae. Many rodent species from this family have been named and their importance to biogeography addressed, but what this fauna can reveal about the palaeoenvironment of the Fayum has yet to be determined. The study of palaeoenvironmental trends begins with a general examination of species diversity and morphology of the specific rodent lineages. A statistical analysis of available molar measurements of Fayum rodents estimates general size and shape trends and changes in rodent diversity through the stratigraphic sequence of the Fayum. This analysis finds stability in species diversity and an increase in the average body size of taxa using molar length as an estimate of body size. The body size pattern of the rodents is similar to the pattern found among the Fayum primates. Analysis of molar length and width has been performed to test whether these variables could discriminate accurately between taxa. If molars that are too worn to be identified by cusp pattern can be identified confidently based on length and width, more specimens could be included in future analyses and a more accurate depiction of the small mammal fauna attained. Length is significantly different between most of the species, and several species can be identified by length and width alone. Length and width relationships were consistent for species within the same genus.Item The postcranial skeletal anatomy of the therocephalian Regisaurus (Therapsida: Regisauridae) and its utilization for biostratigraphic correlation(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Fourie, Heidi; Rubidge, Bruce S.The postcranial morphology of the therocephalian genus Regisaurus from the Lystrosaurus Assemblage Zone of South Africa is described. The remarkably complete state of preservation of the vertebral column has, for the first time, provided a full vertebral count for a therocephalian and demonstrates that it is possible to differentiate between cervical, thoracic, lumbar, sacral and caudal vertebrae. It is demonstrated that some postcranial elements can be used to identify particular therocephalian groups and will be of use in biostratigraphic studies in areas where cranial remains have not been found. A slender scapula, low scapular ridge, shallow scapular depression, short and broad interclavicle, oval sternum, and a small obturator foramen are characteristics of therocephalians known from the Cistecephalus, Dicynodon and Lystrosaurus assemblage zones of the Beaufort Group of South Africa.Item Dental mesowear and the palaeodiets of bovids from Makapansgat Limeworks Cave, South Africa(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Schubert, Blaine W.The palaeodiet of seven bovids from Makapansgat Limeworks Cave are analysed using dental mesowear. Results suggest that Tragelaphus pricei had a highly attritional diet and was thus a browser. Tragelaphus sp. aff. T. angasii and Aepyceros sp. were also browsers, having diets similar in texture to the extant mule deer (Odocoileus hemionus). Gazella vanhoepeni had an intermediate attrition-abrasion wear signal and groups most closely with extant mixed feeders. Redunca darti and Makapania broomi are at the abrasion end of the wear continuum and cluster with living grazers, such as the hippotragines and reduncines. Parmularius braini had a highly abrasive diet similar to extreme grazers like the American bison (Bison bison) and topi (Damaliscus lunatus). The bovid mesowear data were compared to previous palaeodietary studies using taxonomic uniformitarianism, ecomorphology (hypsodonty), and stable carbon isotopes on the same Makapansgat taxa. This comparison showed that the mesowear results are most closely in-line with the isotope data, both of which are non-genetic signals that reflect diet during an extended portion of an animal’s life.Item 15th Biennial Meeting of the Palaeontological Society of Southern Africa, Albany Museum and Rhodes University, 7–10 September 2006(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007)Item Palaeontologia africana Volume 42(Bernard Price Institute for Palaeontological Research, 2007)Item A fresh look at chemical fossil extraction(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) McCrae, Ceri; Potze, StephanyIn this age of microtechnology, now more than ever before, detail is indispensable. In the past, the damage to fossils during retrieval, preparation and storage was an accepted downfall of the scientific process. With the increasing use of advanced techniques, which rely on high-resolution applications such as scanning electron microscopes and microtomography, there is a definite need to improve on the actual fossil extraction methods currently used. The aim of this work is to achieve an ideal method of extraction where the fossil is retrieved in its entirety without adding or taking away any evidence whatsoever.Item New mammutid proboscidean teeth from the Middle Miocene of tropical and southern Africa(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Pickford, MartinThe genus Zygolophodon is widespread but rare in Middle Miocene deposits of Eurasia, and until recently it was not reliably reported from sub-Saharan Africa. Most previous records of the genus in the latter continent are based on specimens of another proboscidean Eozygodon morotoensis. In 1985 a tooth from Tunisia was attributed to Zygolophodon and in 2002 four teeth from Egypt were attributed to the same genus, while in 2005 a fragment of lower third molar was found at Daberas Mine, Orange River, Namibia, and two upper molars were found in the Ngorora Formation, Tugen Hills, Kenya. The purpose of this note is to describe and interpret the Ngorora molars. Two newly discovered specimens of Eozygodon morotoensis from Uganda complete the paper.Item Ammonites from offshore deposits near Bogenfels, Namibia(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Klinger, Herbert Christian; McMillan, Ian K.Pyritized ammonite nuclei and fragments were recovered by vibracore sampling from offshore deposits near Bogenfels, Namibia. Although these could only be identified at genus level, the association of Baculites and Scaphites suggest a Coniacian age for these deposits which conforms with the age of the associated foraminifera.Item Description of an anomalous tortoise (Reptilia: Testudinidae) from the Early Holocene of Zimbabwe(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Broadley, Donald G.An anomalous subfossil tortoise is described from a Holocene cave deposit at Pomongwe in the Matobo Hills, southwest Zimbabwe (Carbon 14 date 9400 ±100 yrs BP). This specimen appears to be unique in its truncated and depressed anterior carapace with loss of the normal second peripheral, but agrees with Kinixys Bell and Impregnochelys Meylan & Auffenberg in having numerous auxiliary scales. It may lack the carapacial hinge of Kinixys. The epiplastron appears most similar to that of a female Chersina angulata Gray.Item Hipparion pomeli sp. nov from the late Pliocene of Ahl al Oughlam, Morocco, and a revision of the relationships of Pliocene and Pleistocene African hipparions(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Eisenmann, Vera; Geraads, DenisThis paper addresses three points: 1) the description of a new species (H. pomeli sp. nov.) of Late Pliocene hipparion from Morocco; 2) preliminary notes on hipparion skulls from Langebaanweg E Quarry (H. hendeyi sp. nov.) and Chad Kossoum Bougoudi; 3) a new interpretation of African hipparion relationships. The Appendix presents practical techniques allowing the estimation of adult dimensions in juvenile skulls and correlations between two mandibular and skull dimensions. H. pomeli was a medium-sized species related to, but smaller than, H. hasumense from East Africa. The distance vomer–basion was small and there was no reduction of the third incisors. The lower cheek teeth were caballine, moderately hypsodont, with moderate ectostylids. The limb proportions were cursorial. H. pomeli differed from the true ‘Eurygnathohippus’ (H. afarense and H. cornelianum) by the basi-cranial proportions and the lack of reduction of the third incisors. H. hendeyi had an extremely short vomer–basion distance, a short distance between the orbit and the POF, primitive teeth, and slender limb bones. It cannot be derived from H. africanum or from H. turkanense. The greatest resemblances are with (the much smaller) H. moldavicum of Taraklia and H. giganteum of Grebeniki. The tentative reconstruction of H. feibeli’s skull indicates a possible relationship with H. hendeyi. The very large skull from Kossoum Bougoudi, Chad, resembles, but is much larger than, the Chinese H. dermatorhinum; its dimensions are compatible with the European H. crassum and the Mongolian H. tchicoicum. It is proposed that more than two migrations gave rise to the various African species of hipparions.Item A non-mammaliaform cynodont from the Upper Triassic of South Africa: a therapsid Lazarus taxon?(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Abdala, Fernando; Damiani, Ross; Yates, Adam; Neveling, JohannThe tetrapod record of the ‘Stormberg Group’, including the Lower Elliot Formation, in the South African Karoo is widely dominated by archosaurian reptiles, contrasting with the therapsid dominion of the subjacent Beaufort Group. The only therapsids represented by skeletal remains in the Upper Triassic Lower Elliot Formation are the large traversodontid cynodont Scalenodontoides macrodontes and the recently described tritheledontid cynodont Elliotherium kersteni. Here we present a fragmentary lower jaw that provides evidence of a third type of cynodont for the Upper Triassic of South Africa. The fossil is tentatively assigned to the Diademodontidae. The latter representative of this family is known from the Late Anisian, and its tentative record in the Norian Lower Elliot Formation, if confirmed, will represent a case of Lazarus taxon. Thus, Diademodontidae apparently disappeared from the fossil record by the end of the Anisian and then reappeared in the Norian of South Africa, a stratigraphic interval of some 21 million years. This new cynodont record, together with the recently described Tritheledontidae, show that cynodonts are now the second most diverse tetrapod group in the Lower Elliot fauna.Item A sabre-tooth felid from Coopers Cave (Gauteng, South Africa) and its implications for Megantereon (Felidae: Machairodontinae) taxonomy(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2007) Hartstone-Rose, Adam; De Ruiter, Darryl J.; Berger, Lee R.; Churchill, Steven E.Metrical and morphological analysis of a new sabre-tooth felid mandible recovered from the Plio-Pleistocene hominid-bearing site of Coopers, South Africa, indicates that it can be assigned to the genus Megantereon, though it is by some measures the smallest individual of this taxon yet described. Comparison of morphological variability within this genus to that found within four extant, medium-sized felid species (Acinonyx jubatus, Neofelis nebulosa, Panthera pardus and P. uncia) and the extinct genus Smilodon (sister taxon of Megantereon) provides confirmation of the suggestion by Martínez-Navarro&Palmqvist (1995, 1996) that Megantereon is a geographically polymorphic genus comprised of at least two species: M. cultridens (Cuvier, 1824) of North America and Europe and M. whitei (Broom, 1937) of Africa and Europe.