Gymnocalycium hossei (Haage) A.Berger, Kakteen: 226, 341. 1929 sec. Charles 2009
- ≡Echinocactus hossei Haage ex A.Berger, Kakteen: 226. 1929 syn. sec. Charles 2009
- =Echinocactus mazanensis Backeb. in Cact. J. (Croydon) 1: 133. 1932 syn. sec. Charles 2009
- ≡Gymnocalycium mazanense (Backeb.) Backeb. in Kakteen-Freund 1: 12. 1933 syn. sec. Charles 2009
- =Echinocactus mazanensis var. breviflorus Backeb. in Kakteen-Freund 1: 134. 1932 syn. sec. Kew WCVP (2019)
- ≡Gymnocalycium hossei var. breviflorum (Backeb.) H.Till in Gymnocalycium 21 (Sonderausgabe): 816. 2008 syn. sec. Kew WCVP (2019)
- =Gymnocalycium nidulans Backeb., Kaktus-ABC: 293. 1936 ["1935"] syn. sec. Charles 2009
- ≡Gymnocalycium hossei var. nidulans (Backeb.) H.Till in Gymnocalycium 21 (Sonderausgabe): 816. 2008 syn. sec. Kew WCVP (2019)
- =Gymnocalycium weissianum Backeb., Kaktus-ABC: 296. 1936 ["1935"] syn. sec. Charles 2009
- =Gymnocalycium rhodantherum var. cinerascens H.Till in Gymnocalycium 17: 584. 2004 syn. sec. Kew WCVP (2019)
- –Gymnocalycium weissianum var. atroroseum Backeb., Cactaceae 3: 1763. 1959, nom. inval., syn. sec. Kew WCVP (2019)