Description from Flora of China
Subshrubs glabrous, monoecious or dioecious. Stems green when dry, erect, ascending, or climbing, terete, to 200 cm tall, woody at base, usually with galls on mid portion of internodes; stems, stipules, petioles, and leaves densely covered with cystoliths. Stipules caducous, green, oblong, 13-23 mm, papery, longitudinally 2-ribbed; petiole unequal in length, (0.5-)2-7 cm; leaf blade elliptic- or ovate-lanceolate, unequal in size, (3-)10-22 × (1.3-)4-6.5 cm, papery, 3-veined, lateral veins 8-10 each side, transverse, external secondary veins indistinctly anastomosing by margin, cystoliths conspicuous, base slightly oblique, broadly cuneate or rounded, margin serrulate or obscurely serrulate, apex acute to caudate-acuminate. Inflorescences in pairs, of mixed sexes; male inflorescence a cymose panicle or few branched, interrupted spike; peduncle to 4.5 cm; female inflorescence a cyme. Male flowers pedicellate, in bud obovoid, ca. 1.5 mm; perianth lobes (3 or)4, cymbiform, connate about 1/2 of length, subapically corniculate, persistent perianth lobes 0.5-0.7 mm, 1/2 as long as achene; stamens (3 or)4; rudimentary ovary conic. Female flowers subsessile; perianth lobes dimorphic; staminodes oblong. Achene asymmetrically ovoid, ca. 1.3 mm, compressed. Fl. May-Jul, fr. Aug-Oct.
* Shaded wet places in forests, ravines; 400-1400 m. Taiwan.