Chamaesyce hirta (Linnaeus) Millspaugh.

Herbs, annual, 30-60(-70) cm tall, usually few branched. Root fibrous, 3-5 mm. Stem branched from middle or above, ascending to erect, rarely prostrate, ca. 3 mm thick, with mixture of long yellow-brown multicellular hairs and much shorter white hairs. Leaves opposite; stipules membranous, triangular, 0.8-1.7 mm, caducous; petiole 1-3.5 mm; leaf blade lanceolate-oblong, long elliptic, or ovate-lanceolate, 10-50 × 3-16 mm, adaxially green to red, sometimes with purple blotch along midrib, abaxially gray-green, both surfaces pilose, denser abaxially, base slightly oblique, margin entire or few serrulate below middle, finely serrulate above middle, apex acuminate or obtuse. Cyathia in dense, often headlike, pedunculate cymes at upper nodes, peduncle to 25 mm, all parts very hairy; involucre campanulate, ca. 1 × 1 mm, pilose, marginal lobes 5, triangular-ovate; glands 4, red, rounded to transversely elliptic, center slightly sunken, appendages white to reddish, narrowly elliptic to obdeltoid, to 0.3 × 0.2 mm, margin entire to slightly undulate. Male flowers 4 or 5; anthers red. Female flower: pedicel short, exserted from involucre; ovary 3-angular, sparsely pilose; styles free; stigma slightly 2-lobed. Capsule 3-angular, 1-1.5 × 1-1.5 mm, smooth, shortly pilose; fruiting peduncle to 1.5 mm. Seeds subglobose-tetragonal, 0.7-0.9 × 0.4-0.5 mm, reddish, sides transversely furrowed; caruncle absent. Fl. and fr. Jun-Dec. 2n = 18*.

This species is used medicinally.

Roadsides, fields, scrub, open forests. Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hunan, Jiangxi, Sichuan, Taiwan, Yunnan [tropical and subtropical regions in both hemispheres].