Wannaganosuchus is based on SMM P76.28.247, a mostly complete skull and postcranial skeleton missing some vertebrae, coracoids, part of the feet, ribs, and other pieces. A few small bony scutes are also assigned to the genus, but not to the type specimen. SMM P76.28.247 was found semi-articulated in the lower part of the Bullion Creek Formation, near the base of a lignitic clay layer deposited in a marsh setting on a floodplain. Wannaganosuchus was named in 1982 by Bruce R. Erickson. The type species is W. brachymanus; the specific name means "short forefoot".[1]