Open AccessA new atoposaurid crocodylomorph from the Morrison Formation (Upper Jurassic) of Wyoming, USA
Author(s) -
John Foster
Publication year - 2018
Publication title -
geology of the intermountain west
Language(s) - English
Resource type - Journals
ISSN - 2380-7601
DOI - 10.31711/giw.v5.pp287-295
Subject(s) - autapomorphy , taxon , paleontology , geology , morphology (biology) , geography , biology , phylogenetics , biochemistry , gene
A left mandible of a small crocodyliform found in the Upper Jurassic Morrsion Formation of northeastern Wyoming represents the first occurrence of the atoposaurid Theriosuchus in North America. The specimen demonstrates lower jaw morphology, including heterodonty (as indicated by alveolus shape), similar to Theriosuchus and Knoetschkesuchus, but autapomorphies and a unique combination of characters among these taxa indicate that it is a distinct, new species of Theriosuchus.