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The skull of Nothodipoides (Castoridae, Rodentia) and the occurrence of fossorial adaptations in beavers

Published online by Cambridge University Press:  14 July 2015

William W. Korth*
Affiliation:
Rochester Institute of Vertebrate Paleontology, 265 Carling Road, Rochester, New York 14610

Abstract

The skull and mandible of Nothodipoides Korth are described. There are a number of adaptations present that are shared with other rodents with tooth-digging behavior (procumbent, elongated, and flattened incisors; anteriorly tilted occipital; strongly arched upper diastema). A new tribe of Castoroidinae, Nothodipoidini, is proposed for Nothodipoides and Microdipoides Korth and Stout, based on the fossorial adaptations of the skull, and their generally smaller size. It appears that fossorial adaptations have occurred in castorids at least three times: the Palaeocastorinae (Whitneyan through Arikareean), the primitive beaver Migmacastor (Arikareean), and the Nothodipoidini (late Barstovian through the Clarendonian).

Type
Paleontological Notes
Copyright
Copyright © The Paleontological Society 

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