Volume 40 December 2004

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Browsing Volume 40 December 2004 by Author "Bristowe, Anthea"

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    A juvenile coelophysoid skull from the Early Jurassic of Zimbabwe, and the synonymy of Coelophysis and Syntarsus
    (Bernard Price Institute for Palaeontological Research, 2004-12) 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.
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    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.
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    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.
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    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.