Volume 40 December 2004

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A description of the sedimentology and palaeontology of the Late Triassic–Early Jurassic Elliot Formation in Lesotho
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Bordy, E. M.; Hancox, P. J.; Rubidge, B. S.
Sedimentological studies of the Late Triassic to Early Jurassic Elliot Formation (Karoo Supergroup) in Lesotho have proved to be a fundamental element in our research into the development of the main Karoo Basin of southern Africa. Complementing previous research in SouthAfrica, studies of the architecture of the sedimentary units in the Elliot Formation reveal that there are two contrasting types of sandstone body geometries, each resulting from different fluvial depositional styles. In the lower part of the formation, the sandstones resemble multi-storey channel-fills, interpreted as deposits of perennial, moderately meandering fluvial systems. On the other hand, the upper part of the formation is characterized by mostly tabular, multi-storey sheet sandstones which resulted from ephemeral fluvial processes. Based mainly on changes in the fluvial style and palaeocurrent pattern within the formation, the regional lithostratigraphic subdivision applied to the Elliot Formation in South Africa is applicable in Lesotho as well. This study adds detail and therefore refines the stratigraphic subdivision documented for the South African succession, and as such forms an important framework for palaeontological, palaeoecological and biostratigraphic studies in Lesotho.
The ultrastructure of Upper Palaeozoic and Mesozoic pollen from southern Africa and Asia
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Zavada, Michael S.
The dispersed pollen taxa Cycadopites, Monosulcites, Bennetitteaepollenites, Pityosporites, and Inaperturopollenites recovered from Permian to Jurassic sediments in southern Africa and Asia were examined ultrastructurally. Cycadopites, Monosulcites, Bennetitteaepollenites and Inaperturopollenites wall structure is characterized by homogeneous outer layer that is variously lacunate, and is underlain by a lamellated basal layer. Only one species of Monosulcites recovered from Jurassic sediments of Afghanistan showed a well-developed tectum, an infrastructural layer composed of columellae, or irregularly shaped columellae underlain by a basal layer. The saccate pollen of Pityosporites has an infrastructural layer of irregularly shaped anastomosing rods, the sacci are formed by an expansion of infrastructural layer in the region of the saccus (i.e. protosaccate sensu Scheuring). A majority of Permian, Triassic and Jurassic saccate and non-saccate monosulcate pollen is characterized by limited morphological diversity with regard to sculpturing and wall structure type compared to the diversity in angiosperm monosulcate pollen; however, there are pre-Cretaceous monosulcate pollen types that exhibit angiospermous pollen characteristics.
Early development of the mammalian superficial masseter muscle in cynodonts
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Abdala, Fernando; Damiani, Ross
The masseter muscle is a hallmark of the jaw-closing mechanism of modern mammals, acting in concert with other mandibular adductor muscles to fine-tune oral food processing. The model explaining the origin of this muscle within non-mammalian therapsids involves the differentiation of a masseter-like muscle from a primitive external adductor, a downward migration of the masseter insertion on the mandible, and a division and distribution of the muscle to a condition that is similar to that in living mammals. The presence of a suborbital process of the jugal, which is interpreted as the site of origin for the superficial masseter, has been previously regarded as the earliest putative morphological evidence used to infer masseteric division. The suborbital process is first recorded in late Early Triassic (c. 245 Ma) cynognathian cynodonts. Here it is shown that primitive galesaurid cynodonts of earliest Triassic age (c. 251 Ma) display a distinct angulation of the zygomatic arch below the orbit, indicating the presence of a divided masseter amongst more basal cynodonts. This alters the timing of masseter muscle evolution by showing that the downward migration and division of the masseter occurred simultaneously, prior to the evolution of advanced cynodonts (=eucynodonts).
Palaeontologia africana Volume 40
(Bernard Price Institute for Palaeontological Research, 2004)
A juvenile coelophysoid skull from the Early Jurassic of Zimbabwe, and the synonymy of Coelophysis and Syntarsus
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Bristowe, Anthea; Raath, Michael A.
Several authors have drawn attention to the close similarities between the neotheropod dinosaurs Coelophysis and Syntarsus. Reconstruction and analysis of a skull from a juvenile specimen of Syntarsus (collected from the Forest Sandstone Formation of Zimbabwe) show that cranial characters previously used to distinguish these taxa and justify their generic separation (namely the presence of a ‘nasal fenestra’ in Syntarsus and the length of its antorbital fenestra), were based on erroneous reconstructions of disassociated cranial elements. On the basis of this reinterpretation we conclude that Syntarsus is a junior synonym of Coelophysis. Variations are noted in three cranial characters – the length of the maxillary tooth row, the width of the base of the lachrymal and the shape of the antorbital maxillary fossa – that taken together with the chronological and geographical separation of the two taxa justify separation at species level.
A new species of Plesiogulo (Mustelidae: Carnivora) from the Late Miocene of Africa
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Haile-Selassie, Yohannes; Hlusko, Leslea J.; Howell, F. Clark
A new species of Plesiogulo (Plesiogulo botori sp. nov.) is described from 5.5–6.0 Ma deposits in East Africa. This new fossil material comes from two localities: Lemudong’o in southern Kenya, and Adu Dora, in the Afar Depression of Ethiopia. The new mustelid species is larger than all known OldWorld Plesiogulo species and extends the temporal and spatial range of the genus inAfrica. Plesiogulo botori sp. nov. documents the earliest occurrence of the genus in Africa in general and the first evidence of its occurrence in late Miocene deposits of eastern Africa. Associated mammalian fauna at both localities where the species has been found indicate a closed/wooded habitat for the genus. This and other occurrences of the genus across Europe, Asia, and the New World indicate that the genus Plesiogulo was geographically widely dispersed during the upper Tertiary.
On the use of percussion cartridges to extract fossils from hard breccia
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Latham, A.G.; Crawford, T.C.
The use of percussion cartridges (caps) affords a simple, quick, controlled and safe way to remove pieces of hard breccia from around fossils or to remove breccia pieces that contain fossil material.We have demonstrated its use over two field seasons to remove pieces of breccia containing quite small animal bones and it is as good as, or better than, the use of jackhammer drills and other methods. Safety procedures are simple but must be strictly followed at all times.
Immaturity vs paedomorphism: a rhinesuchid stereospondyl postcranium from the Upper Permian of South Africa
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Pawley, Kat; Warren, Anne
The postcranial skeleton of a medium-sized rhinesuchid from the Late Permian Dicynodon Assemblage Zone of South Africa is described. The well-preserved, articulated specimen consists of a partial skull, vertebral column and ribs, pectoral girdle, proximal limb elements, and ventral scales. Interesting features rarely preserved in stereospondyls include the extensive ventral scales and the pectinate anterior border of the interclavicle. SAM-PK-K10021 is of an average size for a rhinesuchid, but possesses a poorly ossified postcranial skeleton in comparison to larger rhinesuchid specimens. The scapulocoracoid lacks an ossified coracoid plate, the humerus lacks a supinator process, and the femur lacks a well-developed internal trochanter and adductor blade. Despite its relatively large size, SAM-PK-K10021 is an immature stage of a large rhinesuchid, thus contributing to our knowledge of the changes to the postcranial skeleton that occur during ontogeny. The assessment of heterochronic processes, especially paedomorphism, in the postcranial skeleton of temnospondyls, and the implications for cladistic analysis, are discussed.
Damaliscus niro horns from Wonderwerk Cave and other Pleistocene sites: morphological and chronological considerations
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Thackeray, J. F.; Brink, J. S.
Wonderwerk Cave, situated near Kuruman in the Northern Cape Province of South Africa, has yielded well-preserved horns of many antelope, including three horn fragments of Damaliscus niro. These specimens were discovered in the course of guano-mining operations in the 1940s. Remarkably, they retain a keratinous sheath. Dimensions of Pleistocene horn cores from Sterkfontein, Olduvai, Cornelia-Uitzoek, Florisbad and Maselspoort are used to assess the Wonderwerk specimens. Assuming that morphological variability can be used to assess relative chronology, we suggest that the Wonderwerk specimens date to the Middle Pleistocene, intermediate in age between specimens from Florisbad (between 400 000 and 100 000 years BP) and Cornelia-Uitzoek (c. 800 000 years BP). One of the Wonderwerk specimens has a radiocarbon date of close to the limit of the method.We interpret this to reflect an indefinite age of greater than 40 000 years ago. This is not in conflict with the suggested Middle Pleistocene age of the specimens. The horns are of further interest in that the keratin sheaths have carbon-nitrogen ratios that suggest the presence of protein suitable for ancient-DNA analysis.
A traversodontid cynodont of African affinity in the South American Triassic
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Abdala, F.; Sa-Teixeira, A.M.
The Traversodontidae represent one of the most diverse and abundant families of non-mammaliaform cynodonts, particularly in Gondwanan faunas of Middle to Late Triassic age. Although a great diversity of traversodontids is known for South American (approximately nine species) andAfrican (six to seven species) Triassic faunas, the record of the group in these continents does not show similarities beyond the family level. Here we describe a new traversodontid, Luangwa sudamericana, from the Santa Maria Formation of southern Brazil, which is most similar to the Anisian traversodontids Luangwa drysdalli from the upper portion of the Ntawere Formation in Zambia, and Scalenodon angustifrons from the Manda Formation in Tanzania. Features in common with these African taxa are oval-outlined upper postcanines presenting an anterior labial cingulum. The new species is similar to L. drysdalli in a number of features, including the presence of a posterior cingulum in the upper postcanines, anterior cingulum in front of the transverse crest in the lower postcanines, short snout, enormous orbits and short temporal region. Differences with L. drysdalli are the less developed posterior cingulum behind the upper transverse crest that does not extend along the entire posterior border of the tooth, and the presence of a well-defined posterior accessory cusp on the sectorial crest of the upper postcanines. The comparison of the quadrate, preserved in situ in the squamosal notch of the new taxon, and that from other traversodontids, suggests that the quadratojugal is involved in the formation of the lateral condyle of the traversodontid suspensorium. Luangwa represents the first genus of traversodontid, and the second of non-mammaliaform cynodont shared by South American and African faunas. A significant biochronological implication of this finding is that part of the Santa Maria Formation may now be considered Anisian in age, and thus older than generally recognized for the unit.
The first use of bone tools: a reappraisal of the evidence from Olduvai Gorge, Tanzania
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Backwell, Lucinda R.; d’Errico, Francesco
Purported early hominid bone tools from Olduvai Gorge are studied for microscopic traces of use-wear, and evidence of intentional flaking by knapping. Comparative microscopic analyses of the edges of the purported tools, and areas far from the potential functional zone, as well as edges of bone pieces from the remainder of the assemblage, show that possible modifications due to utilization are not distinguishable from features attributed to post-depositional abrasion. Taphonomic analysis of the bone tool collection, a control sample of bone shaft fragments from the remainder of the Olduvai assemblage, and experimentally broken elephant long bones, identifies significant differences in the size and type of mammals represented. The bone tool collection records an abundance of large to very large mammals, while the control sample comprises mostly medium-size bovids. Puncture and cut-marks occur on one third of the bone tool collection, and on only a few pieces in the control sample, suggesting hominids were the agent responsible for the breakage of most of the bones previously described as tools. Analysis of the number, location and length of flake scars in the three assemblages, reveals that a reduced proportion of purported bone tools bear invasive, contiguous, often bifacially arranged removals, not seen in the control or experimental collections. This makes these specimens good candidates for having been shaped and used by early hominids. Complete bones with tool-generated puncture-marks, previously interpreted as anvils, are interpreted here as hammers used on intermediate stone tools.
A non-destructive investigation of the skull of the small theropod dinosaur, Coelophysis rhodesiensis, using CT scans and rapid prototyping
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Bristowe, Anthea; Parrott, Andrew; Hack, Jonothan; Pencharz, Mervyn; Raath, Michael
To solve preparation problems encountered in an exceptionally fragile skull of the small theropod dinosaur, Coelophysis rhodesiensis, CT scans were taken of the partially prepared skull, from which a three-dimensional wax model was built using a ‘reverse engineering’ rapid prototyping technique. The resulting wax model was then consulted to trace and describe cranial elements of the dinosaur that were otherwise concealed by the matrix or overlying bones, which could not be removed without risk of damage to the original fossil bone.
New skulls of Kolpochoerus phacochoeroides (Suidae: Mammalia) from the late Pliocene of Ahl al Oughlam, Morocco
(BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH, 2004) Geraads, Denis
The discovery of two male skulls of Kolpochoerus phacochoeroides from the late Pliocene of Ahl al Oughlam in Morocco, and the revision of the whole collection from this locality, allows us to extend the description of this North African form, to estimate its sexual dimorphism and the extent of individual variation in a large isochronous sample, to reveal some ontogenic changes, and to confirm its distinction as a species on its own, as its cranial proportions (large occipital, short snout) and tooth characters (lack of enamel on upper canines, reduced incisors and premolars, complicated third molars) set it clearly apart from the East and South African forms. A cladistic analysis shows that K. phacochoeroides and Hylochoerus are the terminal branches of the Kolpochoerus clade, which is the sister-group of Potamochoerus.
The first use of bone tools: a reappraisal of the evidence from Olduvai Gorge, Tanzania
(Bernard Price Institute for Palaeontological Research, 2004-12) Backwell, Lucinda R; d’Errico, Francesco
Purported early hominid bone tools from Olduvai Gorge are studied for microscopic traces of use-wear, and evidence of intentional flaking by knapping. Comparative microscopic analyses of the edges of the purported tools, and areas far from the potential functional zone, as well as edges of bone pieces from the remainder of the assemblage, show that possible modifications due to utilization are not distinguishable from features attributed to post-depositional abrasion. Taphonomic analysis of the bone tool collection, a control sample of bone shaft fragments from the remainder of the Olduvai assemblage, and experimentally broken elephant long bones, identifies significant differences in the size and type of mammals represented. The bone tool collection records an abundance of large to very large mammals, while the control sample comprises mostly medium-size bovids. Puncture and cut-marks occur on one third of the bone tool collection, and on only a few pieces in the control sample, suggesting hominids were the agent responsible for the breakage of most of the bones previously described as tools. Analysis of the number, location and length of flake scars in the three assemblages, reveals that a reduced proportion of purported bone tools bear invasive, contiguous, often bifacially arranged removals, not seen in the control or experimental collections. This makes these specimens good candidates for having been shaped and used by early hominids. Complete bones with tool-generated puncture-marks, previously interpreted as anvils, are interpreted here as hammers used on intermediate stone tools.
A non-destructive investigation of the skull of the small theropod dinosaur, Coelophysis rhodesiensis, using CT scans and rapid prototyping
(Bernard Price Institute for Palaeontological Research, 2004-12) Bristowe, Anthea; Parrott, Andrew; Hack, Jonathan; Pencharz, Mervyn; Raath, Michael
To solve preparation problems encountered in an exceptionally fragile skull of the small theropod dinosaur, Coelophysis rhodesiensis, CT scans were taken of the partially prepared skull, from which a three-dimensional wax model was built using a ‘reverse engineering’ rapid prototyping technique. The resulting wax model was then consulted to trace and describe cranial elements of the dinosaur that were otherwise concealed by the matrix or overlying bones, which could not be removed without risk of damage to the original fossil bone.
Table of Contents
(Bernard Price Institute for Palaeontological Research, 2004-12)
A description of the sedimentology and palaeontology of the Late Triassic–Early Jurassic Elliot Formation in Lesotho
(Bernard Price Institute for Palaeontological Research, 2004-12) Bordy, EM; Hancox, PJ; Rubidge, BS
Sedimentological studies of the Late Triassic to Early Jurassic Elliot Formation (Karoo Supergroup) in Lesotho have proved to be a fundamental element in our research into the development of the main Karoo Basin of southern Africa. Complementing previous research in SouthAfrica, studies of the architecture of the sedimentary units in the Elliot Formation reveal that there are two contrasting types of sandstone body geometries, each resulting from different fluvial depositional styles. In the lower part of the formation, the sandstones resemble multi-storey channel-fills, interpreted as deposits of perennial, moderately meandering fluvial systems. On the other hand, the upper part of the formation is characterized by mostly tabular, multi-storey sheet sandstones which resulted from ephemeral fluvial processes. Based mainly on changes in the fluvial style and palaeocurrent pattern within the formation, the regional lithostratigraphic subdivision applied to the Elliot Formation in South Africa is applicable in Lesotho as well. This study adds detail and therefore refines the stratigraphic subdivision documented for the South African succession, and as such forms an important framework for palaeontological, palaeoecological and biostratigraphic studies in Lesotho.
A new species of Plesiogulo (Mustelidae: Carnivora) from the Late Miocene of Africa
(Bernard Price Institute for Palaeontological Research, 2004-12) Haile-Selassie, Yohannes; Hlusko, Leslea J; Clark Howell, F
A new species of Plesiogulo (Plesiogulo botori sp. nov.) is described from 5.5–6.0 Ma deposits in East Africa. This new fossil material comes from two localities: Lemudong’o in southern Kenya, and Adu Dora, in the Afar Depression of Ethiopia. The new mustelid species is larger than all known OldWorld Plesiogulo species and extends the temporal and spatial range of the genus inAfrica. Plesiogulo botori sp. nov. documents the earliest occurrence of the genus in Africa in general and the first evidence of its occurrence in late Miocene deposits of eastern Africa. Associated mammalian fauna at both localities where the species has been found indicate a closed/wooded habitat for the genus. This and other occurrences of the genus across Europe, Asia, and the New World indicate that the genus Plesiogulo was geographically widely dispersed during the upper Tertiary.
A traversodontid cynodont of African affinity in the South American Triassic
(Bernard Price Institute for Palaeontological Research, 2004-12) Abdala, F; Sa-Teixeira, AM
Traversodontidae represent one of the most diverse and abundant families of non-mammaliaform cynodonts, particularly in Gondwanan faunas of Middle to Late Triassic age. Although a great diversity of traversodontids is known for South American (approximately nine species) andAfrican (six to seven species) Triassic faunas, the record of the group in these continents does not show similarities beyond the family level. Here we describe a new traversodontid, Luangwa sudamericana, from the Santa Maria Formation of southern Brazil, which is most similar to the Anisian traversodontids Luangwa drysdalli from the upper portion of the Ntawere Formation in Zambia, and Scalenodon angustifrons from the Manda Formation in Tanzania. Features in common with these African taxa are oval-outlined upper postcanines presenting an anterior labial cingulum. The new species is similar to L. drysdalli in a number of features, including the presence of a posterior cingulum in the upper postcanines, anterior cingulum in front of the transverse crest in the lower postcanines, short snout, enormous orbits and short temporal region. Differences with L. drysdalli are the less developed posterior cingulum behind the upper transverse crest that does not extend along the entire posterior border of the tooth, and the presence of a well-defined posterior accessory cusp on the sectorial crest of the upper postcanines. The comparison of the quadrate, preserved in situ in the squamosal notch of the new taxon, and that from other traversodontids, suggests that the quadratojugal is involved in the formation of the lateral condyle of the traversodontid suspensorium. Luangwa represents the first genus of traversodontid, and the second of non-mammaliaform cynodont shared by South American and African faunas. A significant biochronological implication of this finding is that part of the Santa Maria Formation may now be considered Anisian in age, and thus older than generally recognized for the unit.
Acknowledgements
(Bernard Price Institute for Palaeontological Research, 2004-12)