Subspecies, varieties, forms and cultivars of plants belonging to the Ferocactus wislizeni group

• Ferocactus wislizeni Britton & Rose: (subsp. wislizeni) Central spines 4, forming a cross, the lowermost stoutest, and often hooked, 8-10 cm long. Radial spines about 12 needle- to bristle-like, to 5 cm. Flowers yellow to yellowish orange to red, Distribution: central and southern Arizona, southern New Mexico, southwestern Texas, and northwestern Mexico in Chihuahua, Sonora, and Sinaloa.
• Ferocactus wislizeni subs. ajoensis Fencl & Kalas: has slender columnar stem, longer, denser and more robust spines and earlier and longer flowering period during the summer months. Distribution: Arizona (Pima, Pinal, Maricopa and Yuma counties).
• Ferocactus wislizeni var. albispinus (Toumey) Y.Itô
• Ferocactus wislizeni var. falconieri (Orcutt) Y.Itô
• Ferocactus wislizeni subs. herrerae (J.G.Ortega) Pilbeam & Bowdery: Central spines 6, grey, ribbed, angled or hooked at the tip, to 10 cm (3.9 in) long and 5 mm wide. Radial spines several, white, twisted, radiating. Flowers yellow with red midveins. Distribution: Sinaloa, Sonora, and Durango, Mexico.
• Ferocactus wislizeni var. phoeniceus (R.E.Kunze) Y.Itô
• Ferocactus wislizeni subs. tiburonensis (G.E.Linds.) Pilbeam & Bowdery: Central spines 4, forming a cross, round in cross section, lower one sometimes flattened, to 9 cm long. Radial spines awl shaped, similar to the centrals, not bristle-like. Flowers yellow. Distribution: Tiburon Island, Gulf of California, Mexico.