New information on the morphology and stratigraphic range of the mid‐Permian gorgonopsian Eriphostoma microdon Broom, 1911. (16th February 2015)

• Record Type: Journal Article
• Authors: Kammerer, Christian F.; Smith, Roger M. H.; Day, Michael O.; Rubidge, Bruce S.; Angielczyk, Kenneth
• Is Part Of: Papers in palaeontology. Volume 1:Number 2(2015)
• Page Start: 201
• Page End: 221
• Publication Date: 2015-02-16
• Subjects: Paleontology -- Periodicals; 560.5
• DOI: 10.1002/spp2.1012
• Languages: English
• ISSNs: 2056-2802

Abstract

<abstract abstract-type="main" id="spp21012-abs-0001"> <title>Abstract</title> <p>New specimens of the oldest gorgonopsian taxon <italic>Eriphostoma microdon</italic> from the <italic>Pristerognathus</italic> Assemblage Zone (AZ) of South Africa significantly improve our understanding of the anatomy of this taxon. The new specimens consist of nearly complete skulls and lower jaws and allow for a more complete diagnosis of <italic>Eriphostoma</italic> than was possible based on the poorly preserved holotype. In addition to the characteristic palatal dentition and delta‐shaped palatine bosses previously recognized for <italic>Eriphostoma</italic>, this taxon can be diagnosed by the presence of three close‐packed upper postcanines occupying an indented margin of the maxilla, a large, tetragonal‐to‐rounded preparietal bone, and large, paired interorbital depressions expanding outwards in front of the pineal boss. The revised diagnosis permits <italic>Eoarctops vanderbyli</italic>, <italic> Galesuchus gracilis</italic>, and <italic>Scylacognathus parvus</italic> to be synonymized with <italic>Eriphostoma microdon</italic>, as previously suspected. Among gorgonopsians, <italic>Eriphostoma</italic> is most similar to <italic>Aelurosaurus</italic> and <italic>Gorgonops</italic>, although these similarities are likely plesiomorphic for Gorgonopsia. <italic>Eriphostoma</italic> ranges from the <italic>Tapinocephalus</italic> AZ (where it is the only valid gorgonopsian known from the Karoo Basin) through the <italic>Pristerognathus</italic> AZ (where it co‐occurs with <italic>Gorgonops</italic>).</p> </abstract>