J. Arizona-Nevada Acad. Sci. 33: 150. 2001.
Shrubs, ± erect, densely branched, 0.5–1.1 (–1.5) m. Stem segments yellow to gray-green, 6–40 × 2.5–4 cm; tubercles prominent, 1–1.5 (–2) cm; areoles subcircular to obdeltate, 5–7 × 4.5–5 mm; wool tan to yellow, aging gray. Spines 12–25 (–30) per areole, gold to pale-brown, aging dark-brown, longest to 3 cm; sheaths translucent yellow to pale-brown. Glochids in adaxial tuft and scattered along margin, yellow to pale-brown, of irregular lengths. Flowers: inner tepals yellow-green suffused with bronze, pale-red, or purple-brown, 20–35 mm; filaments dark bronze-red to magenta; anthers yellow, sometimes sterile; style rose-pink (at least distally); stigma lobes cream. Fruits grayish tan, 25–30 × 15–30 mm, dry, tuberculate, densely spiny; tubercles prominent, subequal or basal ones longest; areoles 24–32. Seeds rare, tan, circular, flattened, 5–6 mm diam., with 1–2 shallow depressions; girdle smooth. 2n = 66.
Phenology: Flowering spring (Mar–May).
Habitat: Dry, rocky slopes
Elevation: 300-1200 m
Calif., Mexico (Baja California)