Xerophyte

Central Spines

1-3, lance shaped, reddish at first, becoming brownish or grey, 30-80 mm long, upper one, or rarely 2 spines, much elongated, erect or connivent over the top of the plant,flattened, thin, somewhat annulate.

Description

Stenocactus phyllacanthusSN|906]]SN|906]], best known as Echinofossulocactus phyllacanthusSN|911]]SN|911]], is a round cactus with the upper central spines three-pronged long, flattened grass-like and numerous wavy ribs, it is distinguished from similar wavy ribbed species by its small yellowish flowers and few radial spines. Older plants sometimes get corky near the base. There is a general lack of understanding on the taxonomic position of this species within the genus and thus is it no possible to define either the spatial or systematic limits of the taxon. There is much variation within the current taxon, and most of the "phyllacanthus" - especially those with pink o violet striped flowers - may correspond to other species.

Note

Stenocactus tricuspidatusSN|912]]SN|912]] (a multiheaded species) has been moved into Stenocactus phyllacanthusSN|906]]SN|906]] in the most recent revisions.

Flowers

Born singly or 2-3 together, produced sporadically all-through spring and summer, yellowish white with brownish red throats, 15 to 20 mm long. Tube short. Inner perianth-segments acute.

Spines

Shorter and less dense than in other species the main one broad and flattened.

Ribs

(25-)30 to 35(-60), very thin, strongly undulate.

Stem

Usually solitary, occasionally few branched, depressed globose to short cylindrical, dull green or dark bluish green, flat or somewhat depressed apically, 3 to 15 cm. high, 4-10 cm in diameter.

Radial Spines

2-7, straight, weak-subulate, white, bristly or awl shaped, andspreading 4-9 mm long.

Fruits

Small, green.

Areoles

Only a few to a rib (mostly 1-2), white-tomentose when young.