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Horolodectes sunae, an enigmatic mammal from the late Paleocene of Alberta, Canada

Published online by Cambridge University Press:  20 May 2016

Craig S. Scott ,
Michael W. Webb  and
Richard C. Fox
Craig S. Scott*
Affiliation:
Laboratory for Vertebrate Paleontology, Department of Biological Sciences, University of Alberta, Edmonton, Canada T6G 2E9, ,
Michael W. Webb
Affiliation:
Imperial Oil Resources, Mackenzie Delta/Beaufort Geoscience, 237 Fourth Avenue S.W., P.O. Box 2480, Station ‘M’, Calgary, Alberta, Canada T2P 3M9,
Richard C. Fox
Affiliation:
Laboratory for Vertebrate Paleontology, Department of Biological Sciences, University of Alberta, Edmonton, Canada T6G 2E9, ,
*
∗Corresponding authoro: C. S. Scott, Laboratory for Vertebrate Paleontology, Department of Biological Sciences, University of Alberta, Edmonton, Canada T6G 2E9, <[email protected]>
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Abstract

A new eutherian mammal of uncertain taxonomic position is described on the basis of well-preserved dental and gnathic specimens collected from localities in the Paleocene Paskapoo Formation of Alberta, Canada. Horolodectes sunae new genus and species is represented by seven incomplete maxillae, eleven incomplete dentaries, and numerous isolated teeth, together preserving nearly all of the postcanine dentition. The unusual dentition of Horolodectes n. gen. consists of trenchant, posteriorly leaning premolars in combination with comparatively primitive molars, suggestive of a masticatory cycle that consisted primarily of shearing and, to a lesser degree, horizontal grinding. Included among the specimens of Horolodectes is an incomplete dentary of an immature individual, with the teeth having been in various stages of eruption at the time of death. Although the dentition of Horolodectes broadly resembles that of apheliscine hyopsodontids, pentacodontine pantolestids, and “ungulatomorphs” among eutherian mammals, significant differences in the coronal structure of the teeth prevent unequivocal referral of Horolodectes to any of these groups, or to any known eutherian order.

Type
Research Article
Information
Journal of Paleontology , Volume 80 , Issue 5 , September 2006 , pp. 1009 - 1025
Copyright
Copyright © The Paleontological Society 

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