Alternate name: Fishhook Pincushion

Family: Cactaceae, Cactus view all from this family

Description A low, cylindrical cactus with 1 or several stems and many hooked spines; flowers pink or lavender.
Flowers: 3/4-1" (2-2.5 cm) wide, near top of stem; petals many, each about 1/2" (1.5 cm) long.
Stems: Usually less than 4" (10 cm) long, occasionally to 1' (30 cm); 1 1/2-3" (4-7.5 cm) wide.
Spines: About 1/4-1/2" (6-13 mm) long, in clusters at tips of nipples; central spine 1/2" (1.5 cm) long, hooked, surrounded by 18-28 shorter, straight, light tan or brownish-pink spines.
Fruit: 1/2-1" (1.5-2.5 cm) long, broadest above middle, smooth, at first green, after several months red.
Height: To 6" (15 cm).

Flower April-May.

Habitat Dry, gravelly places in deserts and arid grasslands.

Range Southeastern California east to western Texas and south to northern Mexico.

Discussion The genus name refers to the projections on the stems, which resemble mammary glands. Similar species of Mammillaria and Coryphantha are distinguished by the position of the flower relative to the cluster of spines. In Coryphantha older projections have a groove on the upper side. Both genera have some species with hooked spines. The wild-plant enthusiast who wishes to find reference to Graham's Nipple Cactus in more technical literature must check under two more scientific names: the long-used M. microcarpa and the recently used M. milleri. The synonymy reflects historical problems in nomenclature and the difficulty of obtaining a satisfactory classification, problems that are very common in the Cactaceae.