Fishhook Barrel Cactus
Synonym: Echinocactus wislizeni, Echinocactus arizonicus
The species name is also spelled wislizenii. It honors Dr. Friedrich Adolph Wislizenus, a German botanist who traveled extensively in the Southwest, and whose specimens were subsequently sent to A. De Candolle.
It has 15 to 25 ribs, with areoles about 1 inch apart (2.5 cm), 4 central spines, and around 20 radial spines.