Xerophyte

Central Spines

1-4, sometimes absent, occasionally as many as 8(-11), stout, needle-like, straight or curved,up to to about 11 mm long, dart reddish brown to yellowish brown contrasting with the paler radial spines.

Seeds

brown.

Description

Mammillaria microheliaSN|28215]]SN|28215]] is a particularly attractive small columnar, perennial cactus both solitary or forming clumps and bearing cream or brown spines, discolouring with age. Has creamy-white to purplish flowers in spring. Spines are arranged like the rays of the sun.

Tubercles

Blunt conical, rounded apically, keeled, without latex, axils naked or slightly woolly, later naked.

Flowers

Bell-shaped, to 16 mm long and in diameter. Tepals creamy-white or yellowish-green, with or without a pink-reddish to purple central band, but also pink or purplish. Stigmas green, short. Outer perianth segments lanceolate, to about 9 mm long, 1 mm wide, pointed or rounded at the top. Inner perianth segments about 5 mm long, 2 mm wide, whitish, yellowish, or pink glossy. Stamens numerous, filaments pure white, anthers pale yellow, all curved towards the centre. Style thin, white. Stigma lobes 5, about 1 mm long upright, pale green, protruding slightly over the stamens.

Stem

Cylindrical, medium green, to 15(-25) cm or more high, 3-5(-6) cm in diameter.

Radial Spines

Numerous (30 to 50), radiating, straight or often slightly curved backward, white to yellowish, 4-6 mm long.

Fruits

Pale green, or pale pink.