Volume 43 April 2008

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    Makapansgat Limeworks stratigraphy and the singular case of Member X
    (Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, 2008-04) Lathan, Alf; Warr, Ginette
    Within the infilling sequence of the western Limeworks a newly recognized unit, Member X, lies stratigraphically between the Member 1 massive speleothem and the Member 2 red silts. Member X consists firstly of a subaqueous mammillary layer that is ubiquitous to the whole of the Limeworks. It is succeeded by a series of intercalated clastic sediments and calcite-rich layers that is confined to the area between the Original Ancient Entrance and the Classic Section and which is terminated by a second subaqueous carbonate layer. The evidence suggests that surface sediments were washed into a carbonate-rich pool created by seepage water and, from the presence of several articulated skeletons, the Original Ancient Entrance during this phase appears to have acted as an animal trap. There are a few blocks of Member X to be found in the Limeworks dumps that have been placed in the Member 2 rows but which should be prepared separately. From the evidence of the intercalated carbonate and clastic layers it appears that Member X was deposited slowly at first and then speeded up probably because erosion caused retreat of the entrance. Member X has several unusual features including a unique pseudo-breccia layer of co-deposited calcite-mud formations, deposition of aragonite that increases with height, and calcite-aragonite layers that invert the stratigraphy on overhanging walls and ceilings but not on the floors.
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    A new cynodont record from the Tropidostoma Assemblage Zone of the Beaufort Group: implications for the early evolution of cynodonts in South Africa
    (Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, 2008-04) Botha-Brink, J.; Abdala, F.
    A new specimen of cynodont has been recovered from the lower Upper Permian levels of the Tropidostoma Assemblage Zone of the South African Karoo Basin. A series of characters, including the presence of an interpterygoid opening, triconodont postcanine teeth, which are circular in crown view, a probable lingual cingulum, and most significantly, the presence of a masseteric fossa high on the coronoid process, allows this specimen to be assigned to the Procynosuchidae. However, unlike most procynosuchids, precanine teeth are absent and the incisors are represented by four left and five right upper and probably, three lower teeth. Considering the small size of the new specimen from the Tropidostoma Assemblage Zone we identify it as a juvenile Procynosuchus delaharpeae, the only species currently recognized in the genus. The low number of incisors and absence of precanines in this specimen are interpreted as ontogenetic variation (i.e. juvenile characters). This discovery extends the biostratigraphic range of Procynosuchus, as it is now recorded in three assemblage zones, indicating that this taxon is the longest-lived cynodont in the Karoo Basin. The new specimen of Procynosuchus and the recently described Charassognathus gracilis, are the oldest global records of cynodonts, and indicate an earlier initial radiation of this lineage than was previously thought.
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    Palaeontologia africana Volume 43
    (Bernard Price Institute for Palaeontological Research, 2008)
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    Palaeontological Society of Southern Africa - 15th Biennial Meeting, Grahamstown, 2006 - Additional Abstracts
    (Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, 2008-04) Various
    The following three abstract were inadvertently omitted from the list of abstracts published in Palaeontologia africana (2007) 42, 117–136.
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    Re-evaluation of the postcranial skeleton of the Triassic dicynodont Kannemeyria simocephalus from the Cynognathus Assemblage Zone (Subzone B) of South Africa
    (Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, 2008-04) Govender, Romala; Hancox, Phillip John; Yates, Adam M.
    Kannemeyeria simocephalus is probably the best known Middle Triassic dicynodont from South Africa and has been the standard against which other Triassic dicynodonts are compared. In the past studies have concentrated on the cranial morphology of K. simocephalus and its implications for Triassic dicynodont taxonomy and phylogeny. There has been little work on the postcranial anatomy of K. simocephalus, which remains poorly understood. An analysis of the postcranial skeleton of K. simocephalus has identified characters that diagnose the postcranial skeleton. These include a tubercle on the proximo-posterior corner of the medial surface of the acromion; almost straight lateral border of the femur. Material previously described as K. simocephalus by Pearson (1924) and Cruickshank (1975) was also included in this study. Some of the material was found to be significantly different from what is understood to be K. simocephalus and as a result has been included a separate study. It was therefore concluded that the referred specimen BP/1/5624 is currently the most complete and positively identified as K. simocephalus.
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    A second specimen of Blikanasaurus (Dinosauria: Sauropoda) and the biostratigraphy of the lower Elliot Formation
    (Bernard Price Institute for Palaeontological Research, university of the Witwatersrand, 2008-04) Yates, Adam M.
    A second specimen of the rare basal sauropod Blikanasaurus cromptoni, is recorded from a site in the Ladybrand district of the Eastern Free State, South Africa. The specimen consists of a right metatarsal 1 that originated from the upper 20mof the lower Elliot Formation. It can be referred to B. cromptoni on the basis of its small size and highly robust proportions, which distinguish this taxon from all other sauropodomorphs. This record extends the geographic distribution of B. cromptoni north into the region of the main Karoo Basin where the Elliot Formation is dramatically thinner. It also extends the known stratigraphic range of B. cromptoni up from the base of the Elliot Formation into a position near the top of the lower member. This new record, combined with other new discoveries, supports the hypothesis that the thin northern part of the lower Elliot Formation is a condensed section that is largely, if not entirely, coeval with the thicker southern sections.
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    Size and shape of the human foot bone from Klasies River main site, South Africa
    (Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, 2008-04) Zipfel, Bernhard; Kidd, Robert S.
    Rightmire et al. (2006) recently described three human metatarsal bones of Middle Stone Age antiquity from Klasies River Mouth (KRM) main site, South Africa. One of these, a complete adult left first metatarsal is broadly similar to Late Stone Age (LSA) Holocene skeletons from the southern coastal margins of the Cape, and based on size, was suggested to be from a male. Our analysis subjected the KRM first metatarsal and comparative human samples to selected morphometric analyses, in an attempt to test the hypothesis regarding shape associated sexual dimorphism as a means to estimate sex in the KRM individual. The results support earlier suggestions that it falls within the range of early Holocene variation, this being very narrow both in size and shape. The size-independent shape-associated morphology, however, suggests that the individual may be female. Even though these findings imply that the KRM individual may have been female based on sexually dimorphic shape-associated discrimination in LSA Holocene people, they are not conclusive and that this individual could probably be assigned to either sex.
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    Taxonomic status of the reptile genus Procolophon from the Gondwanan Triassic
    (Bernard Price Institute for Palaeontological Research, University of the Witwatersrand, 2008-04) Cisneros, Juan Carlos
    The specific composition of the genus Procolophon in Brazil, South Africa and Antarctica is discussed in the light of new data. It is found that P. pricei and P. brasiliensis, two species described from Brazil, fit within the pattern of ontogenetic variation of the type species P. trigoniceps, and they are here considered junior synonyms. The South African species P. laticeps, characterized by the presence of a temporal fenestra, is no longer considered valid. The peculiar temporal openings of this species are regarded here as an anomalous condition without taxonomic significance. The only complete skull known from Antarctica shows a unique feature consisting of an elliptical depression in the palate. The interpretation of this structure is ambiguous because it may also be attributable to individual variation, and this specimen is provisionally kept within P. trigoniceps. Therefore, only the type species, P. trigoniceps, is recognized in Gondwana. This species occupies a wide geographic range, from the Paraná Basin to the Transantarctic Mountains.