Synonyms
Gymnocalycium castellanosii subsp. armillatum (Piltz) Papsch
Gymnocalycium castellanosii var. armillatum Piltz
Gymnocalycium bozsingianum Schütz
Gymnocalycium castellanosii var. bozsingianum (Schütz) Piltz
Gymnocalycium castellanosii var. rigidum H.Till
Gymnocalycium castellanosii subsp. bozsingianum (Schütz) Amerh. & H.Till
Gymnocalycium ferox (Backeb.) Slaba
Gymnocalycium hybopleurum var. ferox Backeb.