Description from Flora of China
Diasperus urinaria (Linnaeus) Kuntze; Phyllanthus alatus Blume; P. cantoniensis Hornemann; P. cantoniensis Schweigger (1812), not Hornemann (1807); P. chamaepeuce Ridley; P. lepidocarpus Siebold & Zuccarini; P. leprocarpus Wight; P. nozeranii Rossignol & Haicour.
Annual herbs, erect or procumbent, up to 80 cm tall; stem much branched at base; branches prostrate to ascending, winged, hispidulous along one side. Leaves distichous; stipules ovate-lanceolate, ca. 1.5 mm, base conspicuously auriculate; petiole very short; leaf blade papery, oblong or oblong-obovate or nearly linear, sometimes slightly falcate, 4-10 × 2-5 mm, abaxially gray-green or pale, or sometimes reddish tinged, adaxially bright or dark green, base mostly obtuse, sometimes conspicuously oblique, margin ciliate, apex rounded, obtuse, or acutely mucronulate; lateral veins 4 or 5 pairs, conspicuous. Plants monoecious. Flower fascicles male along distal part of branchlets, 2-4-flowered, female along middle and lower part of branchlets, 1-flowered; pedicel ca. 0.5 mm, with 1-2 bracteoles at base. Male flowers: sepals 6, elliptic to oblong-obovate, 0.3-0.6 × 0.2-0.4 mm, yellowish white, apex obtuse; disk glands 6, green; stamens 3; filaments completely united into a slender column. Female flowers: pedicels ca. 0.5 mm; sepals 6, ovate to ovate-lanceolate, subequal, ca. 1 mm, margin membranous, yellowish white, persistent in fruit; disk orbicular, entire; ovary ovoid or spherical, with conspicuous raised scales; styles 3, free, bifid at apex, lobes revolute. Capsules globose, 2-2.5 mm in diam., with reddish blotches, scurfy-tuberculate. Seed 3-sided, 1-1.2 × 0.9-1 mm, light grayish brown, with 12-15 sharp transverse ridges on back and sides, often with 1-3 deep circular pits on side. Fl. Apr-Jun, fr. Jul-Nov.
Dry fields, roadsides, wastelands, forest margins; below 100-600 m. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Xizang, Yunnan, Zhejiang [Bhutan, India, Indonesia, Japan, Laos, Malaysia, Nepal, Sri Lanka, Thailand, Vietnam; South America].