Varieties 2 (1 in the flora): sw United States, nw Mexico.

Plant: small tree or shrub, much-branched, the older branches at base of crown dark-brown, clinging to solitary or multiple trunks, 0.3-1.5(-3) m tall; STEM segments green to light green, the ultimate ones usually very easily detached, 4-13(-18) cm long, (2-)4-5.5 cm in diam.; tubercles salient, obdeltoid, 6-12 mm long. AREOLES white-, yellow- to brownish-felty, aging gray, elliptic-deltoid, 3-7 cm long, 2-4 mm wide Leaves: SPINES at most areoles, pale yellow to yellow to tan, aging dark brown, interlaced, and nearly completely obscuring stem, 3-11(-15) per areole; sheaths uniformly whitish or pale yellow, baggy; distal spines terete, erect-spreading, largest (10-)20-30 mm long; basal spines subterete to flattened, spreading to deflexed, the largest (10-)15-25 mm long. GLOCHIDS yellow, in a broad apical crescent, sometimes extending basally along areole margins, 3-4 mm long Flowers: inner tepals pale green, sometimes red-tipped, spatulate, emarginate-apiculate, often erose, (15-)20-35 mm long; filaments pale green to green, the anthers yellow-orange; style light green; stigmas cream to green Fruit: yellow, strongly tuberculate, cylindric to broadly obconic, with umbilicus to 10 mm deep, fleshy-leathery, becoming spineless, losing bristle-spines of young fruit, (15-)22-40 mm long, (8-)16-20(-28) mm in diam.; areoles 36-76, equally spaced; SEEDS, 2.5-4 mm long, 2.2-3.5 mm wide, pale yellow, in gelatinous mass, angular to squarish in outline, warped, the sides smooth, each with 1-2 large depressions, the girdle smooth or as a very narrow marginal ridge REFERENCES: Pinkava, Donald J. 1999. Cactaceae. Ariz. – Nev. Acad. Sci. 32(1).