匍匐大戟 pu fu da ji

Chamaesyce prostrata (Aiton) Small.

Herbs, annual, 15-19 cm tall. Root fibrous. Stems many from base, prostrate, usually light red or red, occasionally green or yellow-green, glabrous or sparsely pubescent. Leaves opposite; stipules long triangular, easily fallen; petiole very short or sessile; leaf blade elliptic to obovate, 3-7(-8) × 2-4(-5) mm, adaxially green, sometimes with light red or red abaxially, margin entire or irregularly finely serrulate, apex rounded. Cyathia single, axillary or few clustered, peduncle 2-3 mm; involucre turbinate, ca. 1 × 1 mm, usually glabrous, sometimes with some pubescence, marginal lobes 5, triangular or rounded; glands 4, appendages white, extremely narrow. Male flowers many, usually shorter than cup. Female flower pedicellate, exserted from involucre; ovary sparsely pubescent on angles; styles nearly connate at base; stigma 2-lobed. Capsule 3-angular, ca. 1.5 × 1.4 mm, smooth, glabrous except for white hairs along angles. Seeds ovoid-tetragonal, ca. 0.9 × 0.5 mm, yellow, each side with 6 or 7 transverse furrows; caruncle absent. Fl. and fr. Apr-Oct.

Roadsides, fields, villages, scrub. Fujian, Guangdong, Hainan, Hubei, Jiangsu, Taiwan, Yunnan [tropical and subtropical Americas; naturalized in many parts of the Old World].