Description from Flora of China
Branches slender, slightly pilose when young, ultimately glabrous. Petiole filiform, slightly puberulent, 2-6 cm; blade very variable, ovate or sagittate-ovate, 3-12 × 2-8 cm, abaxially slightly pilose, ultimately glabrous, adaxially indistinctly punctate-scabrid, 3-lobed, base deeply emarginate, margin minutely denticulate or coarsely serrate, apex long, acute-acuminate. Tendrils filiform, 2-fid. Male inflorescence racemose, sometimes paniculate, shortly villous, many flowered, main rachis 1-13 cm, shortly villous; bract linear, ca. 3 mm, villous; calyx segments linear-lanceolate, 2-3 × 0.5-1 mm, margin dentate; corolla segments lanceolate, 2-3 × 1-1.5 mm at base, scarcely villous, 1- or 3-veined, apex narrowly subulate; staminal filaments slightly dilated at apex, ca. 0.5 mm, pilose; anthers ca. 0.3 mm. Female flowers solitary or fasciculate; calyx and corolla as in male flowers; ovary ovoid, verrucose. Fruit ovoid or oblong-ellipsoid, 1.6-2.5 × 1-2 cm, verrucose, operculate, 2-4-seeded. Seed plano-convex, broadly ovoid, 11-13 × 8-9 mm, 3-4 mm thick, both surfaces reticulate, base slightly attenuate. Fl. Jul-Sep, fr. Sep-Nov.
The whole plant and its seeds are used medicinally.
Growing on watersides. Anhui, Fujian, Guangxi, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Liaoning, Shandong, Sichuan, S Xizang, W Yunnan, Zhejiang [India, Japan, Korea, Laos, Thailand, Vietnam].