Xerophyte

Seeds

Dark brown, helmet-shaped, shining, with a large depressed hilum, the margins being turned in.

Forma Rubra

The red schizochromic form (Astrophytum myriostigma cv. Kikko f. rubraSN|1845]]SN|26133]]) has bright orange-red stems due to the absence (or reduced production) of chlorophyll pigments

Flowers

Like those of the well known A. myriostigma, pale-yellow, shining-silk.

Blooming Season

A. myriostigma seems to flower independently of day length, flowering asynchronously and intermittently throughout the warm months from the end of winter to the start of autumn. Plants may take up to six years to flower.

Spines

None.

Ribs

Usually 5, sometimes 4(or 3) that increase to eight or more with age (rarely even 10), vertical, regular, deep, prominent, very broad and acute.

Stem

Pentagonal to almost spherical, dimension 22-40 cm tall, 5-10 cm in diameter.

Fruits

2-2,5 cm in diameter, greenish to tannish-red, covered with brown, overlapping scales, with long wool in their axil.