Plants annual, from threadlike taproots. Stems erect, sparingly branched below inflorescence, 4-sided, 3-25 cm, glabrous or sparsely hairy. Leaves sessile, crowded at base, shiny; blade oblanceolate to obovate and spatulate (proximal) or linear-lanceolate (distal), 0.5-1.5 cm × 0.5-2 mm, base round, apex acuminate, glabrous, often ciliate on margins. Inflorescences terminal, 3-21-flowered (rarely more) cymes; bracts linear-lanceolate, 1-12 mm, scarious distally, herbaceous proximally, often ciliate on margins. Pedicels ascending to erect, ± straight in fruit, 2-25 mm, glabrous. Flowers 2-3 mm diam.; sepals 5, with 3 prominent, ridged veins, very narrowly lanceolate, to acicular, 2.8-4.2 mm, margins wide, scarious, apex acuminate, glabrous; petals 5 or absent, 1-3 mm, shorter than sepals, blade apex 2-lobed; stamens 3-5; styles 3, spreading, becoming curled, ca. 0.3 mm. Capsules green or straw colored, narrowly ovoid, 2-3 mm, shorter than sepals, apex obtuse, opening by 3 valves, splitting into 6; carpophore absent. Seeds brown, round, 0.5-0.7 mm diam., minutely tuberculate. 2n = 20, 40. Flowering spring. Dry, open habitats: sand dunes, stream banks, rocky outcrops, open woodlands, beneath boulders, disturbed areas; 0-2000 m; B.C.; Ariz., Calif., Idaho, Mont., Nev., Oreg., Utah, Wash.

Plant: Annual, ascending to erect, 3-25 cm, glabrous or sparsely hairy; taproot thread-like; Stem: internodes glabrous or hairs scattered Leaves: imple, crowded near base; blade 5-15 mm, margin smooth, shiny, often ciliate; lower oblanceolate to obovate; upper linear-lanceolate INFLORESCENCE: terminal cyme, few-several-flowered; bracts scarious; pedicels ascending to erect, in fruit ± straight Flowers: sepals 5, 2.8-4.2 mm, ± lanceolate, acuminate, glabrous, margin widely scarious, ribs in fruit ± 3; petals 5, 0.2-0.5 X sepals or 0; stamens 10, sometimes fewer; styles 3, 0.2-2.8 mm Fruit: Fruit: capsule, ± ovoid to cylindric-oblong; teeth 6(8,10), ascending to recurved; Seed 0.5-0.7 mm, brown; surface minutely tubercled Misc: Sand dunes, streambanks, open woodlands, beneath boulders, disturbed areas; < 1500 m.