Gymnocalycium prochazkianum subsp. ivoi Halda & Milt in Acta Mus. Richnov., Sect. Nat., 13: 10. 2006 Gymnocalycium prochazkianum subsp. ivoi Halda & Milt in Acta Mus. Richnov., Sect. Nat., 13: 10. 2006Taxon for this nameGymnocalycium prochazkianum subsp. ivoi Halda & Milt