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A new temnospondyl amphibian from the Late Triassic of Texas

Published online by Cambridge University Press:  20 May 2016

John R. Bolt  and
Sankar Chatterjee
John R. Bolt
Affiliation:
Department of Geology, Field Museum of Natural History, Roosevelt Road at Lake Shore Drive, Chicago, Illinois 60605,
Sankar Chatterjee
Affiliation:
Museum of Texas Tech University, Lubbock, Texas 79409,
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Abstract

A skull representing a new genus and species of Late Triassic temnospondyl, Rileymillerus cosgriffi, is described from the Cooper Canyon Formation, upper Dockum Group of Garza County, Texas. Rileymillerus resembles Latiscopus disjunctus in size and proportions, but the very poorly preserved unique type specimen of L. disjunctus indicates that the taxon should be considered a nomen dubium. Characters of R. cosgriffi include its small size combined with relatively small laterally-facing orbits, relatively high skull, lack of lateral line canals, lateral exposure of the palatine on the skull surface, and lack of otic notch/quadrate angle. No postcranial material can be definitely associated, although we describe a partial vertebral column that might pertain to R. cosgriffi. Relationships of R. cosgriffi are uncertain. The possibilities of a close relationship to Almsauridae, Tupilakosauridae or (especially) Brachyopoidea are explicitly examined, but for the present we consider R. cosgriffi as Temnospondyl incertae sedis. Characters described in the text have been converted to the tripartite (part, feature, state) standardized format developed for the PRESERVE web site, and are presented as a 125-character data matrix in the Appendix.

Type
Research Article
Information
Journal of Paleontology , Volume 74 , Issue 4 , July 2000 , pp. 670 - 683
Copyright
Copyright © The Paleontological Society 2000

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