in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 198. 1859.
Plants 15–100 cm. Leaves: stipules 5–6 mm, margins deeply toothed; petiole 2–10 cm; blade ± round in outline, 8–15 cm diam., moderately lobed, lobes 1/3–1/2 blade length, base broadly cordate, margins dentate, teeth and lobe apices acuminate, aristate. Staminate flowers: calyx funnel-shaped, tube 4–6 mm, distally flaring, stinging hairs absent, lobes 4–8 mm; stamens subequal, filaments all connate most of length; staminodes 3, threadlike. Pistillate flowers: sepals 10–12 mm; stigmas 12. Capsules 10–12 mm. Seeds brown, sometimes mottled, 9–11 mm.
Phenology: Flowering May–Sep.
Habitat: Grasslands, desert scrub, oak woodlands.
Elevation: 1100–1600 m.
Ariz., Mexico (Baja California Sur, Sinaloa, Sonora).
In the flora area, Cnidoscolus angustidens is restricted to southern Arizona.