Annuals. Stems unbranched or branched basally, branched distally, (1-)2-6(-8) dm. Basal leaves: petiole 1-4(-5) cm; blade lanceolate to linear-lanceolate, (2-)3-7(-10) cm × 4-15(-20) mm, base cuneate to attenuate, margins pinnately lobed to coarsely dentate. Cauline leaves: (proximalmost) petiole 1-4(-5) cm, (distalmost) shortly petiolate or subsessile; blade linear to narrowly lanceolate, base cuneate, margins usually entire, rarely dentate, or repand. Fruiting pedicels divaricate to slightly reflexed, (6-)8-14 (-22) mm. Flowers: sepals (2.5-)3-4 × 1-1.5 mm, pubescent abaxially; petals white or lavender, 4-7(-8) × (2.5-)3-4(-5) mm, attenuate to claw, claw 1-1.5 mm, expanded basally; filaments white, 2-3.5 mm; anthers 0.7-1 mm. Fruits: each valve usually transversely ovoid-oblong, rarely suborbicular, 4-5.5(-6) × (4-)5-7(-7.5) mm (often longer than wide), base slightly rounded, apex truncate, with or without narrow wing beyond indurated part surrounding seeds, glabrous or pubescent; style 0.5-1(-1.2) mm. Seeds suborbicular-ovoid, 2-3 × 1.5-2 mm. 2n = 18. Flowering Feb-Oct. Sandy roadsides, sandstone knolls, sand hills and dunes, sandy streambeds and dry washes, desert flats; 1000-2200 m; Ariz., Colo., Nev., N.Mex., Tex., Utah; Mexico (Chihuahua, Coahuila).
Notes: fruit with two round lobes, flat; pedicels 7-10mm, spreading References: J.C. Hickman, ed. The Jepson Manual. W.B. McDougal. Seed plants of Northern Arizona. USDA website.ASU specimens.