Description

Key Characters:

Growth Form: Annual herbs.

Stems: Stems 2.5–10 dm long, branched, sparsely to moderately covered with prickles.

Roots:

Leaves: Leaves simple. Alternate. Blades oblong–oblanceolate, pinnately lobed ½–¾ to midrib. Surfaces glaucous, margin teeth tipped with a prickle, both surfaces sparsely covered with prickles along veins. Margins somewhat sinuate–dentate, the teeth tipped with a prickle. Simple leaves sessile, upper ones usually somewhat clasping the stem. Stipules absent.

Flowers: Flowers terminal, solitary. Flowers bisexual (perfect), actinomorphic, buds subglobose, 1.2–1.6 cm long, sparsely prickly. Calyx of (2)3(–6) sepals each with a subterminal horn tipped by a prickle, horns terete (cylindrical), 5–10 mm long, caducous. Petals bright yellow, distinct, 1.7–3 cm long. Stamens 30–50; anthers linear, coiled after dehiscence, dithecal, opening by longitudinal slits. Ovary superior, 4–6-carpellate, 1-celled; stigma 3–7-lobed.

Fruit: Capsules oblong to broadly ellipsoid; 3–4.2 cm long; each valve with 9–15 prickles; the longest one 7–10 mm long. Seeds numerous; 1.2–1.5 mm in diameter; subglobose; reticulate; endosperm oily.

Ploidy: 2n = 28

Habitat: Dry; disturbed habitats.

Elevation Range: