Xerophyte

Habit

Simple or budding either at base or near middle, often cespitose, but in small clusters, sometimes 20 cm high.

Central Spines

1 to 3, yellowish-brown, dark-brown to purplish black, when more than one the lower stouter, 12-25 mm long, the longest one usually hooked and standing out perpendicular to the plant surface.

Seeds

Black, shining, pitted, almost globose, 0,8 to 1 mm in diameter.

Description

Mammillaria microcarpaSN|9210]]SN|9210]] has long been a favorite in living collections. It is sensitive to any excess of moisture and does not do well in cultivation, but will reward the skilled growers with ring of fine rose-purple flowers circling the crown of the plant. This plant is generally known under the name of Mammillaria grahamiiSN|9189]]SN|9189]]. This species is quite common in habitat, but variable throughout the region.

Roots

Thickened.

Note

The degree of difference between Mammillaria grahamiiSN|9189]]SN|9189]] and Mammillaria microcarpaSN|9210]]SN|9210]] is still a matter for debate.

Tubercles

Small, ovoid to cylindrical, often bases four-angled or flattened from side to side when old, corky when old. Without latex.

Flowers

Forming a ring around the new growth near top of plant, 2 to 4,5 cm long, broadly funnel-shaped, opening widely, pink, lavender-pink or reddish purple, sometimes white. Outer perianth segments ovate, obtuse, or conical with brownish midlines and short-ciliate margins; inner perianth-segments longer purplish, slender, sometimes with whitish margins, obovate, acuminate. Filaments pink; anthers pale orange. Style longer than stamens, up to 6 mm long above the stamens, purplish; stigma-lobes 6 or 10, linear, light green.

Stem

Globose, conical to short cylindric, light green, up to 20 cm tall (but usually only 7-8 cm), 2,5-8(-11) cm in diameter.

Radial Spines

15 to 35, radiating evenly from the areole, lying flat upon the surface of the plant, interlocking with those of neighboring areoles and nearly hiding flesh of plant, straight, needle-like, white, sometimes with dark brown to reddish tips, slender, rigid, glabrous, 6 to 12 mm long, lateral ones longest. The upper centrals stand up-right just in front of the upper radials, forming a V if there are two of them, but there may be only one.

Fruits

Subglobose to clavate, 12 to 25 mm broad, scarlet, with the dried flower parts remaining upon them. These fruits develop rather slowly, there is a long blooming season, and those started late in the summer remain as small, green, oval structures under the spines until during the winter they dry up without ripening properly at all. For this reason fruits have sometimes been called dimorphic.

Areoles

Dimorphic. The spinous portion, at the tip of the tubercle, is small round or oval, with some white wool at first, but later bare. The floral or vegetative part in the axil is without wool, so the axils are naked.