ATTENTION: This is a Taxon that could easily tangled with Emys wyomingensis ( Echmatemys wyomingensis) has been named in Leidy (1869) based on a left epiplastron. One year later, Leidy (1870a) named Baptemys wyomingensis from the same locality, based on an almost complete shell (Leidy 1873, pl. 11). Leidy (1870a) raised some doubts on the validity of Emys wyomingensis by saying that the epiplastron could belong the same animal as Baptemys wyomingensis. I am not sure if by that he meant the same individual or the same species, but the epiplastron of Emys wyomingensis is certainly a pan-testudinoid and clearly distinct from Baptemys. In the same year, Cope (186970) already suggested the synonymy between the two species, and placed them under Adocus. But shortly after, Leidy (1873) and Hay (1908) provided further evidence on the distinction of these two species. However, in the literature these taxa often get confused.

Adocus wyomingensis was named by Leidy (1870). Its type specimen is ANSP 10074, a partial shell (epiplastron), and it is a 3D body fossil. Its type locality is A few miles from Fort Bridger, which is in a Bridgerian terrestrial horizon in the Bridger Formation of Wyoming.