Herbs perennial, glabrous. Stems ascending, quadrangular, 5--14 cm tall, slender, branched. Leaves sessile, ovate-lanceolate or lanceolate, 0.5--1.6(--2) cm × 1--4 mm, midvein conspicuously raised abaxially, base nearly rounded or cuneate, apex acuminate. Flower solitary, axillary or terminal; bracts leaflike, herbaceous, without membranous margin. Pedicel 1--2 cm, to 3.5 cm in fruit, slender. Sepals 5, ovate-lanceolate, 3.5--4 × ca. 2 mm, 3-veined, margin broadly membranous, apex acuminate. Petals 5, subequaling sepals, 2-cleft nearly to base; lobes linear. Stamens 10, shorter than petals. Ovary suborbicular; styles 3. Capsule ellipsoid, 1.5--2 × as long as persistent sepals, 6-valved. Seeds brown, compressed globose, ca. 1 mm in diam., tuberculate. Fl. May--Jul, fr. Jun--Aug. 2n = 26.

River banks, meadows, fields. Nei Mongol, Xinjiang [Japan, Kazakhstan, Mongolia, Russia; Europe, North America].