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A new early-diverging sphenodontian (Lepidosauria, Rhynchocephalia) from the Upper Triassic of Virginia, U.S.A.

Published online by Cambridge University Press:  10 November 2020

Hans-Dieter Sues
Department of Paleobiology, National Museum of Natural History, MRC 121, P.O. Box 37012, Washington, DC20013-7012, USA
Rainer R. Schoch
Staatliches Museum für Naturkunde Stuttgart, Rosenstein 1, D-70191Stuttgart, Germany


A new taxon of sphenodontian reptile, Micromenodon pitti new genus new species is described from the Upper Triassic (Carnian) Vinita Formation of the Richmond basin of the Newark Supergroup in Virginia. It is diagnosed by a dorsoventrally deep facial process of the maxilla that extends for almost the entire anteroposterior length of the bone and by obtusely conical, strongly ribbed additional teeth in the maxilla that comprise a greatly enlarged tooth followed by smaller teeth posteriorly. Phylogenetic analysis found Micromenodon pitti n. gen. n. sp. as an early-diverging sphenodontian with fully acrodont tooth implantation. The maxillary dentition appears functionally suited for processing hard arthropod exoskeletons and snail shells.


Copyright © The Author(s), 2020. Published by Cambridge University Press on behalf of The Paleontological Society

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