Stenocactus pentacanthus (Lem.) A. Berger ex A.W. Hill, Index Kew. 8: 228. 1933 sec. Guzmán & al. 2003
- ≡Echinocactus pentacanthus Lem., Cact. aliq. nov.: 27. 1838 syn. sec. Guzmán & al. 2003
- =Echinocactus violaciflorus Quehl in Monatsschr. Kakteenk. 22: 102. 1912 syn. sec. Guzmán & al. 2003
- =Echinofossulocactus pentacanthus (Lem.) Britton & Rose, Cactaceae (Britton & Rose) 3: 115. 1922 syn. sec. Guzmán & al. 2003
- =Echinofossulocactus violaciflorus (Quehl) Britton & Rose, Cactaceae (Britton & Rose) 3: 114. 1922 syn. sec. Guzmán & al. 2003
- =Stenocactus violaciflorus (Quehl) A. Berger ex A.W. Hill, Index Kew. 8: 228. 1933 syn. sec. Guzmán & al. 2003
- =Echinofossulocactus pentacanthus var. david-boudetianus Bravo in Cact. Suc. Mex. 14: 36. 1969 syn. sec. Guzmán & al. 2003
- =Stenocactus dichroacanthus var. violaciflorus (Quehl) Bravo in Cact. Suc. Mex. 27: 16. 1982 syn. sec. Guzmán & al. 2003
- =Echinofossulocactus crispatus f. pentacanthus (Lem.) P.V. Heath in Calyx 2: 86. 1992 syn. sec. Guzmán & al. 2003
- =Echinofossulocactus crispatus f. violaciflorus (Quehl) P.V. Heath in Calyx 2: 86. 1992 syn. sec. Guzmán & al. 2003
- =Stenocactus pentacanthus subsp. tulensis Halda, Kupcák & Sladk. in Acta Mus. Richnov., Sect. Nat., 7: 37. 2000 syn. sec. Guzmán & al. 2003
- =Stenocactus dichroacanthus subsp. violaciflorus (Quehl) U. Guzmán & Vázq.-Ben. in Cactaceae Syst. Init. 16: 18. 2003 syn. sec. Guzmán & al. 2003