Opuntia echinocarpa Engelmann & J. M. Bigelow var. major Engelmann, Proc. Amer. Acad. Arts 3: 305. 1856; Cylindropuntia acanthocarpa var. ramosa (Peebles) Backeberg; O. acanthocarpa var. major (Engelmann & J. M. Bigelow) L. D. Benson;O. acanthocarpa var. ramosa Peebles, O. echinocarpa var. robustior J. M. Coulter

Shrubs, sprawling, with numerous branches, usually at obtuse angles. Stem segments green to dark green, 8-20(-31) cm; tubercles salient, moderately broad, 1.5-2.5 cm. Spines 14-18(-23) per areole, yellow to deep red-brown, aging gray, not baggy sheathed; major abaxial spines usually deflexed, spreading. Flowers: inner tepals yellow, bronze, or brick red. Fruits spiny; areoles 14-22(-26). 2n = 22.

Flowering spring (Mar-Jun). Sonoran Desert, sandy flats, washes, rocky slopes; 300-900 m; Ariz.; Mexico (Sonora).

Cylindropuntia acanthocarpa var. major hybridizes with C. bigelovii (= C. campii M. A. Baker & Pinkava).