Xerophyte

Description

Discocactus heptacanthusSN|12017]]SN|12017]] is a solitary flattened cactus that form a cephalium at maturity and blooms on warm summer nights. The "aurea" form is a rare chlorophylls-less, golden yellow mutant that can live only grafted onto green columar cacti.

Cephalium

Small, 3-4 cm tall woolly, white to dull pastel with brow or black erected bristles 3-5 cm long.

Spines

Whitish, yellowish or brown becoming grey with age, more or less translucent, needle-like or flattened.

Ribs

10-22, up to 2 cm high, broken up into large, rounded tubercles, with more or less deep furrows between, sometime spiralling.

Stem

Globose or slightly depressed, light to golden yellow, 8-28 cm in diameter, 4,5-15 cm tall (without cephalium)

Areoles

Round or oval, at first tomentose, approx 6-10 per rib (in plants with cephalium).