Echinocactus polycephalus subsp. xeranthemoides (J. M. Coulter) N. P. Taylor

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.