Tephrocactus ferocior Backeb. in Cactus (Paris) 38: 250. 1953 Tephrocactus ferocior Backeb. in Cactus (Paris) 38: 250. 1953is basionym for Opuntia ferocior (Backeb.) G.D.Rowley in Natl. Cact. Succ. J. 13: 5. 1958Taxon for this nameTephrocactus ferocior Backeb.