Xerophyte

Habit

Ii is a very spiny shrubby or columnar cactus, branching basally, 1 to 6 m high depending on the substrate and, perhaps, the rainfall. Occasionally may form treelike specimens with dozens of branches.

Central Spines

6-8(-10), stout, brownish, 6-10 cm long.

Flowers

Borne near the stem tips, 6-11 cm long, 2-4,5 cm wide, quite unusual in that their colour changes from a pale green-yellow (or whitish) upon opening to a delicate purple-pink on maturing. Often with flowers of different colours on the same plant, raising the possibility that the plants can be pollinated by both bats and hummingbirds. Outer tepals dull greenish-brown. Floral tubes curving slightly or A-shaped, with short brown hairs dull reddish-brown or greenish-white. It is self-compatible.

Ribs

14-22, more or less tuberculate.

Stem

numerous, upright or curving, grey-green, 6-10(-15) cm in diameter.

Radial Spines

20-60, thin, yellowish brown, needle-like,1-1,5 cm long.

Fruits

Globose, to 4 cm long, yellowish orange, with short woolly hairs, lightly sweet and edible, though somewhat mealy.Seeds. Black.

Areoles

Usually very thick, to 8 mm in diameter, with long greyish-yellow or orangish wool.