Stems gray-green to yellow-green. Spines red to straw colored, canescent, puberulent, or glab-rous. Fruit scales tan, yellow, or reddish, aging yellow, 16-30 mm, usually longer than dried tepals at fruit apex. Seeds rounded (rarely faceted), 2.4-3.1 mm, smooth (exposed surfaces of testa cells flat or slightly convex, uniformly shiny). 2n = 22.
Flowering Jun-Aug. Rocky hills, slopes, and ledges of canyons, Great Basin and Mojave desert scrub, igneous and calcareous substrates; 500-1700 m; Ariz., Nev.
STEM: gray-green to yellow-green. SPINES: canescent to puberulent, or glabrous. FRUIT: scales commonly yellow to tan, 16-30 mm long. SEEDS: 2.4- 3.1 mm long; rounded, the testa appearing shiny due to surfaces of testa cells being slightly convex to flat. 2N = 22. NOTES: See also parent taxon for further description. Rocky hills and canyons along the Grand Canyon and Little Colorado River: Mohave and Coconino Cos.; elevation 450-1700 m (1400-5100 ft); NV. REFERENCES: Chamberland, Michael. 1995. Cactaceae Part 2. Echinocacrus. J. Ariz. - Nev. Acad. Sci. 29(1): 13.