Eriphostoma was named in 1911 by Robert Broom, based on a poorly preserved specimen collected by the Reverend J. H. Whaits in the town of Fraserburg Road (now Leeu-Gamka), South Africa.

[1] The holotype was accessioned in the American Museum of Natural History with the specimen number AMNH FARB 5524.

[2] Despite its status as one of the oldest known gorgonopsians, its poor preservation meant that the specimen was largely ignored for the rest of the 20th century, and typically regarded as a nomen dubium.

[4] A fifth species of Tapinocephalus AZ gorgonopsian, Broomisaurus planiceps, is probably also synonymous, but it is currently a nomen dubium due to its poor state of preparation.

Like all gorgonopsians, it had five incisors and a canine tooth on each side of the upper jaw, but it had only three small postcanine teeth in its maxilla.