California sandwort

Arenaria brevifolia Nuttall var. californica A. Gray, Proc. Calif. Acad. Sci. 3: 101. 1864; Alsinopsis californica (A. Gray) A. Heller; Arenaria californica (A. Gray) Brewer; A. pusilla S. Watson var. diffusa Maguire; Minuartia pusilla (S. Watson) Mattfeld var. diffusa (Maguire) McNeill

Plants annual. Taproots filiform. Stems widely spreading to erect, green, (1-)2-12 cm, glabrous, internodes of flowering stems 5-10 times as long as leaves. Leaves not overlapping, all evenly spaced, connate proximally, with loose, herbaceous or scarious sheath 0.5-0.7 mm; blade widely spreading, green, concave proximally, flat distally, weakly 1-veined abaxially, linear to awl-shaped or narrowly oblong, 2-5 × 0.2-1.5 mm, flexuous, margins not thickened, scarious proximally, smooth, apex green or purple, acute to often rounded, flat, dull to shiny, glabrous; axillary leaves absent. Inflorescences 5-7(-9)-flowered, open cymes, or rarely flowers solitary; bracts subulate, herbaceous, often scarious-margined proximally. Pedicels 0.2-1.5 cm, glabrous. Flowers: hypanthium disc-shaped; sepals 1-3-veined, midvein sometimes more prominent than lateral veins, broadly lanceolate to elliptic (herbaceous portion narrowly elliptic to oblong), 2.5-2.8 mm, not enlarging in fruit, apex green to purple, rounded to acute, slightly hooded, glabrous; petals elliptic to oblanceolate, 1.5-1.8 times as long as sepals, apex obtuse to rounded, entire. Capsules on stipe ca 0.1 mm, ± ovoid, 3-3.5 mm, longer than sepals. Seeds reddish brown, suborbiculate with radicle prolonged into beak, slightly compressed, 0.4-0.5 mm, minutely papillate. 2n = 26.

Flowering spring-summer. Gravelly or sandy slopes, meadows, chaparral, vernal ponds, roadsides; 10-700(-1500) m; Calif., Oreg.