Gymnocalycium gibbosum var. cerebriformis Speg. in Anales Soc. Ci. Argent. 48: 50. 1899 Gymnocalycium gibbosum var. cerebriformis Speg. in Anales Soc. Ci. Argent. 48: 50. 1899Taxon for this nameGymnocalycium gibbosum var. cerebriformis Speg.