Herbs annual. Stem solitary, quadrangular, 20--30 cm tall, apically branched, pilose. Leaves ovate, orbicular-ovate, or ovate-lanceolate, 1.5--2.5(--4.5) × 0.8--1.2(--1.5) cm, abaxially sparsely hairy, adaxially glabrous, midvein conspicuously protuberant, densely hairy, base rounded, sessile, margin ciliate, apex acuminate. Flowers numerous, in terminal, sparse cymes; bracts ovate, membranous. Pedicel 1--2 cm, subglabrous. Sepals 5, lanceolate, 2--2.5 mm, midvein conspicuous, margin membranous, apex acuminate. Petals 5, shorter than sepals, 2-cleft nearly to base. Stamens 10, shorter than petals. Styles 3. Capsule oblong-ovoid, ca. 1.5 × as long as persistent sepals, 6-valved. Seeds brown-purplish, compressed globose, inconspicuously tuberculate. Fl. Apr--Jul, fr. Jun--Aug.

* Forests, grasslands; (1200--)1500--2900 m. Guizhou, Hubei, Sichuan, Yunnan.