Horridocactus aconcaguensis (F.Ritter) Backeb., Cactaceae 6: 3791. 1962 Horridocactus aconcaguensis (F.Ritter) Backeb., Cactaceae 6: 3791. 1962is new combination for Pyrrhocactus aconcaguensis F.Ritter in Succulenta (Netherlands) 1960: 108. 1960Taxon for this nameHorridocactus aconcaguensis (F.Ritter) Backeb.