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New information on the forefin of Utatsusaurus hataii (Ichthyosauria)

Published online by Cambridge University Press:  14 July 2015

Ryosuke Motani
Ryosuke Motani*
Affiliation:
Department of Zoology, University of Toronto, 25 Harbord Street, Toronto, Ontario, M5S 1A1 Canada
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Abstract

Utatsusaurus hataii, an Early Triassic ichthyosaur from Japan, is represented by exceptionally well preserved materials but is poorly known because of incomplete preparation. Further preparation of the holotype and one of the paratype specimens has revealed nearly complete forefins that are pentadactyl, with no more than five phalanges in any of the digits. The first digit is not well developed, and the fifth distal carpal appears to be absent. The phalanges along the fin margin tend to be lunate; others are flattened cylinders. These findings indicate that the relationship of Utatsusaurus with other Early Triassic ichthyosaurs must be reconsidered.

Type
Research Article
Information
Journal of Paleontology , Volume 71 , Issue 3 , May 1997 , pp. 475 - 479
Copyright
Copyright © The Paleontological Society 

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