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Reassessment of Lower Eocene Seggeurius amourensis: aspects of primitive dental morphology in the mammalian order Hyracoidea

Published online by Cambridge University Press:  20 May 2016

Nicholas Court  and
Mohamed Mahboubi
Nicholas Court
Affiliation:
Sedgwick Museum, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, United Kingdom
Mohamed Mahboubi
Affiliation:
Department des Sciences de la Terre, Université d'Oran, B.P. 16, Oran-Essenia, Algèria
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Abstract

New lower dental material of the fossil hyracoid mammal, Seggeurius amourensis Crochet, 1986, from Eocene deposits of the Southern Atlas in Algeria, has prompted a reevaluation of the genus. The dentition as a whole is first described in detail, thus providing a more precise characterization of the genus than has hitherto been available. Peculiarities, particularly in upper molar morphology, are sufficient to uphold a generic distinction. However, based largely on lower molar morphology Seggeurius amourensis is transferred from the subfamily Geniohyinae to Saghatheriinae. In the upper molars, absence of a postmetacrista and the presence of a preprotocrista continuous with the parastyle are interpreted as primitive features in hyracoids. In the lower molars, extreme reduction of the paracristid and the presence of a mesoconid are also considered primitive for hyracoids. These features together with small size, bunodonty, low crown height, and very simple premolar morphology indicate that Seggeurius amourensis is the most primitive hyrax yet recovered.

Type
Research Article
Information
Journal of Paleontology , Volume 67 , Issue 5 , September 1993 , pp. 889 - 893
Copyright
Copyright © The Paleontological Society 

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