Shrubs, suberect to erect, to 1.5 m. Stem segments bearing elliptic tubercles usually 1.5-3 cm. Spines commonly with 1(-3) central spines much longer. 2n = 22. Flowering spring (Apr-Jul). Chaparral, oak scrub, juniper woodlands, grassy rolling hills, plains; 200-1900 m; Calif.; Mexico (Baja California).