Herbs perennial, stoloniferous, monoecious or dioecious. Stems simple or branched, 50-150 cm tall, woody at base, succulent, swollen between nodes, glabrous. Stipules deciduous, narrowly triangular, ca. 1 mm, membranous; petiole unequal in length, 1-5 cm, puberulent adaxially; leaf blade abaxially pale green, adaxially dark green, elliptic, ovate-elliptic or ovate-oblong, often slightly oblique at base, unequal in size, 5-13 × 3-7 cm, submembranous, 3-veined, lateral veins many, regularly transverse, often ending in a gland, abaxial surface glabrous, adaxial surface pilose, cystoliths fusiform, often conspicuous abaxially, base rounded or subcordate, margin coarsely crenate-serrate or dentate-serrate, apex acuminate, caudate-acuminate, acumen entire. Inflorescences solitary, male a moniliform spike of 3-8 loose glomerules on simple axis, 3-10 cm, glabrous or sparsely puberulent; female inflorescence 1-3.5 cm. Male flowers pedicellate, in bud triangular-ovoid, 2-2.5 mm; perianth lobes 4, connate 1/2 of length, subapically long corniculate, sometimes puberulent; stamens 4; rudimentary ovary inconspicuous. Female perianth lobes unequal, longest lobe subapically corniculate; Achene brownish, broadly ovoid, ca. 1.8 mm, slightly compressed, smooth, but with some cystoliths, enclosed by persistent perianth. Fl. Jun-Aug, fr. Jul-Sep.

Collections from alpine habitats in NW Yunnan, which have puberulent male inflorescences and perianth lobes, may be ecological forms.

* Shaded moist places, rocks; (900-)1400-2400(-3500) m. N Guangxi, Guizhou, W Hubei, W Hunan, Jiangxi, Sichuan, Yunnan.