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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
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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 

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References

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