Grooves to Tubes: Evolution of the Venom Delivery System in a Late Triassic “reptile”

ASU Author/Contributor (non-ASU co-authors, if there are any, appear on document)
Andrew B. Heckert Ph.D., Professor (Creator)
Appalachian State University (ASU )
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Abstract: Venom delivery systems occur in a wide range of extant and fossil vertebrates and are primarily based on oral adaptations. Teeth range from unmodified (Komodo dragons) to highly specialized fangs similar to hypodermic needles (protero- and solenoglyphous snakes). Developmental biolo-gists have documented evidence for an infolding pathway of fang evolution, where the groove folds over to create the more derived condition. However, the oldest known members of venomous clades retain the same condition as their extant relatives, resulting in no fossil evidence for the transition. Based on a comparison of previously known specimens with newly discovered teeth from North Carolina, we describe a new species of the Late Triassic archosauriform Uatchitodon and provide detailed analyses that provide evidence for both venom conduction and document a complete structural series from shallow grooves to fully enclosed tubular canals. While known only from teeth, Uatchitodon is highly diagnostic in possessing compound serrations and for having two venom canals on each tooth in the dentition. Further, although not a snake, Uatchitodon sheds light on the evolutionary trajectory of venom delivery systems in amniotes and provide solid evidence for venom conduction in archosaur-line diapsids.

Additional Information

Andrew B. Heckert, Jonathan S. Mitchell & Hans-Dieter Sues (2010) "Grooves to Tubes: Evolution of the Venom Delivery System in a Late Triassic “reptile” Naturwissenschaften Volume 97 Issue 12 pp. 1117-1121 Version of Record Available from (
Language: English
Date: 2010
Venom, Uatchitodon, Uatchitodon schneideri, Evolutionary trajectory, Triassic

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