Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-18T07:21:35.215Z Has data issue: false hasContentIssue false
  • English
  • Français

The ichthyosaurian tailbend: a verification problem facilitated by computed tomography

Published online by Cambridge University Press:  08 April 2016

C. McGowan
C. McGowan*
Affiliation:
Department of Vertebrate Palaeontology, Royal Ontario Museum, Toronto, Ontario, Canada M5S 2C6; and Department of Zoology, University of Toronto, Toronto, Ontario, Canada M5S 1A1
Get access Rights & Permissions [Opens in a new window]

Abstract

The tailbend, a downward flexure of the vertebral column, is a prominent feature of post-Triassic ichthyosaurs. However, due to the vagaries of preservation and of preparation, its presence cannot be verified in all skeletons. Computed tomography offers a solution to the problem by identifying the wedge-shaped centra that contribute to the tailbend. Leptopterygius tenuirostris appears to have a tailbend, albeit slightly downturned. There is also evidence that its close relative Eurhinosaurus longirostris had a tailbend, too.

Type
Articles
Information
Paleobiology , Volume 15 , Issue 4 , Fall 1989 , pp. 429 - 436
Copyright
Copyright © The Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

Conroy, G. C., and Vannier, M. W. 1984. Noninvasive three-dimensional computer imaging of matrix-filled fossil skulls by high-resolution computed tomography. Science 226:456–458.Google Scholar
Conroy, G. C., and Vannier, M. W. 1985. Endocranial volume determination of matrix-filled fossil skulls using high-resolution computed tomography. Pp. 419–426. In Tobias, P. V. (ed.), Hominid Evolution: Past, Present and Future. Alan R. Liss; New York.Google Scholar
Conroy, G. C., and Vannier, M. W. 1987. Dental Development of the Taung skull from computerized tomography. Nature 329:625–627.Google Scholar
Haubitz, B., Prokop, M., Döhring, W., Ostrom, J. H., and Wellnhofer, P. 1988. Computed tomography of Archaeopteryx. Paleobiology 14:206–213.Google Scholar
Hauff, B. 1953. Das Holzmadenbuch. F. Rau; Ohringen, West Germany.Google Scholar
McGowan, C. 1973. Differential growth in three ichthyosaurs: Ichthyosaurus communis, I. breviceps and Stenopterygius quadriscissus (Reptilia, Ichthyosauria). Life Sciences Contributions, Royal Ontario Musuem 93:1–24.Google Scholar
McGowan, C. 1974. A revision of the longipinnate ichthyosaurs of the Lower Jurassic of England, with descriptions of two new species (Reptilia: Ichthyosauria). Life Sciences Contributions, Royal Ontario Museum 97:1–37.Google Scholar
McGowan, C. 1979. A revision of the Lower Jurassic ichthyosaurs of Germany with descriptions of two new species. Palaeontographica A 166:93–135.Google Scholar
McGowan, C. 1986. A putative ancestor for the swordfish-like ichthyosaur Eurhinosaurus. Nature 322:454–456.Google Scholar
McGowan, C. 1989a. Leptopterygius tenuirostris and other long-snouted ichthyosaurs (Reptilia) from the English Lower Lias. Palaeontology 32:409–427.Google Scholar
McGowan, C. 1989b. Computed tomography reveals further details of Excalibosaurus, a putative ancestor for the swordfish-like ichthyosaur Eurhinosaurus. Journal of Vertebrate Paleontology 9:269–281.Google Scholar
Riess, J. 1986. Fortbewegungsweise, Schwimmbiophysik und Phylogenie der Ichthyosaurier. Palaeontographica A 192:93–155.Google Scholar
Taylor, M. A. 1987. Reinterpretation of ichthyosaur swimming and buoyancy. Palaeontology 30:531–535.Google Scholar