This species is one of 60 that have been described to date. These are distributed from Mexico to South America. It has a spherical body with 10-12 prominent ribs. Seven radial spines and two central spines grow from the areoles. The radial spines are 1.5 cm (0.75 in) long and curved (hence the specific name); the central spines, up to 2.5 cm (1 inch) long, are straight. The cephalium appears only after 10 years and theproduced there are relatively small. The only other spherical with similar cephalia are of the genus Discocactus, but these have large flowers. Identifying the various species of Melocactus is difficult because young plants differ markedly from older individuals.
Imported species are usually more difficult to grow, but plants propagated fromdo very well. The warm conditions of modern houses are suitable for their growth.