Xerophyte

Central Spines

Usually absent.

Description

Discocactus magnimammusSN|12017]]SN|12038]] (now considered a subspecies of Discocactus heptacanthusSN|12038]]SN|12017]]) is a solitary flattened cactus that form a cephalium at maturity. It distinguishes from the standard species for it more numerous ribs (up to 22) that are completely divided into distinct tubercles, and for the short spines that are round in cross section. It produces fragrant flowers on warm summer nights. Flowers are pollinated by moths.

Cephalium

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

Flowers

Nocturnal, fragrant, white (or pale pink), funnel form, nocturnal, 5-7,5 cm long and 5 cm in diameter.

Blooming Season

Flowers come in profusion in summer, out of the cephalium.

Ribs

14-22, up to 2 m high, broken up into large, rounded tubercles, with deep furrows between, sometime spiralling.

Stem

Globose or slightly depressed, light green to grey-green, up to 14 cm in diameter, 7 cm tall (without cephalium)

Radial Spines

5 to 7, 1-2 cm long, amber coloured, round in cross section and slightly recurved inward.

Fruits

Usually white .

Areoles

Round or oval, at first tomentose, approx 8 per rib (in plants with cephalium).