Description from Flora of China
Herbs perennial, rhizomatous, subglabrous, monoecious or dioecious. Stems brownish when dry, 20-100 cm tall, succulent, with galls on mid portion of internodes. Stipules persistent, broadly triangular, ca. 1 mm, membranous, veinless; petiole subequal in length, 1-7 cm; leaf blade abaxially purplish or pale green, adaxially dark green, elliptic or elliptic-lanceolate, subequal in size, 3-18 × 1.8-7 cm, membranous to thinly papery, 3-veined or triplinerved, lateral veins many, transverse, reticulate, prominent abaxially, abaxial surface glabrous, adaxial surface sparsely pilose, base rounded or cuneate, margin serrate or crenate-serrate, apex acuminate or caudate-acuminate. Inflorescences in pairs, male a dichotomously branched paniculate cyme, 2-5 cm overall, peduncle 1-2.5 cm; female cymes sometimes compacted into clusters, 0.7-2 cm. subsessile or shortly pedunculate. Male flowers pedicellate, in bud ca. 2 mm; perianth lobes 4, ovate; stamens 4; rudimentary ovary small, conic. Female flowers subsessile, in bud ca. 1.2 mm; perianth lobes connate at base, unequal, abaxial lobe cymbiform, longer, subapically corniculate; staminodes 3, scale-like, oblong. Achene ovoid, 0.7-0.8 mm, slightly compressed, oblique, verrucose. Fl. Apr-May(-Sep), fr. May-Jul(-Jan).
Because it was found to be a later homonym after publication of the corresponding FOC volume 5, Chen and Monro (Novon 17: 26. 2007) corrrected this as Pilea gracilis Handel-Mazzetti.
Shaded wet places in forests, near streams; 400-1600 m. Chongqing, Fujian, Guangxi, Guizhou, Hainan, Hubei, Hunan, Sichuan, Yunnan [N Vietnam].