Description from Flora of China
Subshrubs glabrous, monoecious. Stems light green when dry, to 200 cm, ca. 1.5 cm in diam.; stems, petioles, and both surfaces of leaf blade densely covered with cystoliths. Stipules deciduous, green, oblong-lanceolate, 10-12 mm, papery, longitudinally 2-ribbed; petiole subequal in length, 2-11 cm; leaf blade abaxially pale green, adaxially dark green, ovate or ovate-lanceolate, subequal in size, 5-17 × 2.5-8 cm, thinly papery, 3-veined, lateral veins 12-18 each side, transverse, prominent abaxially, external secondary veins anastomosing by margin, base rounded or subcordate, margin serrate or crenate-serrate, apex acuminate. Inflorescences unisexual or sometimes mixed sexes, in pairs, a racemelike cyme, few branched, 1-2.5 cm; male glomerules compact. Male flower greenish, pedicellate, in bud pear-shaped, ca. 2 mm; perianth lobes 4, obovate, connate 1/2 of length, subapically corniculate; stamens 4; rudimentary ovary conic. Female flowers pedicellate; perianth lobes lanceolate, ca. 1 mm, persistent perianth 1/3 as long as achene; staminodes minute. Achene greenish brown, ovoid, ca. 1.2 mm, slightly compressed, oblique, densely spiculose-verrucose. Fl. Mar-Apr, fr. May-Jun.
This species is superficially similar to Pilea notata in appearance, but P. notata has only 3 female perianth lobes, longer male cymes, and outer secondary veins that do not anastomose near the margin.
Shaded wet places in forests, near streams; 700-2500 m. S Guizhou, E Xizang, S Yunnan [N Vietnam].