Xerophyte

Habit

Usually solitary, develops a squat and highly ribbed stem with a flattened top.

Central Spines

0-4 straight, terete to angled, sometimes scaly with age, variable in length very short or to 6 (or more) cm long.

Seeds

1,7-2 mm long, 0,5-1 mm broad, net-patterned with polygonal or square areas.

Tubercles

Conical, angled quite pointed, elongate toward the tip but flattened on top,12-27 mm long, 7-15 mm wide, 8-15 mm high.

Flowers

3-5 cm long, 2,7-3 cm in diameter, salmon-pink or whitish, often yellowish in the throat, or occasionally yellowish or magenta with a dark midvein. Tube short, pericarpels coveredwith scales. The plants usually fail to flower until they are 5-9 years old.

Spines

Sometimes absent, very variable in length, depending on the clone, dark, usually black-brown , pale at apex, but also grey, brown or yellow, with a distinctive silvery appearance, and sometimes shredding.

Ribs

20 to 31, rather indistinct, divided into strong tubercles.

Stem

Spherical or somewhat depressed 4-15 cm tall, 9-20 cm across. It can have either a light glaucous-grey or green epidermis sometimes tinged with purple.

Radial Spines

0-5 very similar to the centrals, erect to radiating, straight 3-35(-50) mm long.

Fruits

Spherical ta oblong with scales, 7-9 mm in diameter, greenish or yellowish, slightly fleshy when ripe, opening by basal pore.

Areoles

Round to elongate, mostly more than 2 cm apart and without nectaries.