Lost and Found: Redescription of Chamasaurus dolichognathus Williston 1915 from the Permo-Carboniferous of New Mexico

Abstract Here we describe the “lost” holotype of Chamasaurus dolichognathus from the Permo-Carboniferous Cutler Group of El Cobre Canyon, New Mexico, USA. While C. dolichognathus has been suggested to be either an amniote or amphibian, we conclude that it is more likely a part of pan-Amniota. We also observe that there is little diagnostic material that would assign this specimen to a more specific clade, although the moderate degree of basal tooth infolding could prove to be of diagnostic utility if additional specimens are discovered. However, we declare the species as nomen dubium until such specimens are found.