Genus: Abyssomedon MacDOUGALL & REISZ, 2014
Etymology: Greek, abyssos, "deep pit"; referring to the caves in which the specimen was preserved and would have lived around.

Species: williamsi MacDOUGALL, & REISZ, 2014
Etymology: In honor of Mr Scott Williams, who collected the specimen.

Holotype: BMRP 2998 33a

Locality: Fort Sill, OMNH Locality V51, Dolese Brothers limestone quarry at Richards Spur, Fissure Fills, just west of U.S. Highways 62 & 281, 10.5 miles south of Apache, 6 miles north of Fort Sill, SW 1/2, Sec. 31, T4N, R11W, Comanche County, Oklahoma.

Horizon: Willington Formation (Garber Formation), Summer Group, Arbuckle limestone, (Probably equivalent to the Arroyo Formation of Texas).


Age: Middle Leonardian stage, upper Rotliegendes Epoch, Early Permian.

Material: Fragmentary skull with disarticulated postcranial elements.