Xerophyte

Central Spines

0 to 3 stronger, straight, and about 2 cm long as well.

Seeds

Small, black glossy 1,2-2 x 0,9-1,2 mm.

Roots

Large tap-root connected to the stem base through a slender neck.

Flowers

The flowers arise on the crown, often several at a time, nearly hidden in the dense wool. They are glossy, pale yellow, with broad limb, 5.5 cm in diameter, and with a faint scent. The filaments, anthers and style are yellow, the 7 to 12 lobed stigma darker. The ovary measures about 1 cm across. It is one of the first species to flower, even 2 to 3 year old seedlings may bloom.

Spines

Straight or slightly curved, brownish-black to black (later grey).

Ribs

10 to 17 prominent, divided into large tubercles about 7 mm high.

Stem

Globular flattened in the young plant, later columnar, 4-20 cm tall, 4-10 cm across, pale green or olive green eventually lightly tinged with brown in the sun.

Fruits

1-1.3cm in diameter, reddish.

Habit

It is a geophytic cactus arising from a large tuberose root. It is at first solitary but can slowly branch from the base to form moderately large clump.

Blooming Season

Flowers throughout the whole summer.

Radial Spines

4 to 9 straight or slightly curved, stoutly needle-like, 5-20 mm long.

Areoles

Round 3-10 mm in diameter, 5-15 mm apart and covered with white or brown felt.