Menispermum acutum Thunberg in Murray, Syst. Veg., ed. 14, 892. 1784; Cocculus diversifolius Miquel (1867), not Candolle (1817); C. diversifolius var. cinereus Diels; C. heterophyllus Hemsley & E. H. Wilson; M. diversifolium Gagnepain; M. diversifolium var. molle Gagnepain; Sinomenium acutum var. cinereum Diels ex Rehder & E. H. Wilson; S. diversifolium Diels.

Woody vines, to more than 20 m. Old stems gray, bark irregularly and longitudinally striate. Branches terete, regularly striate, puberulent to glabrous. Petiole 5-15 cm, striate, glabrous or puberulent; leaf blade cordate-ovate to broadly ovate, sometimes (3-)5-9-lobed, 6-15 cm or longer, leathery to papery, tomentose when young, or only glabrous adaxially and puberulent abaxially, usually glabrous when old, base often deeply cordate with narrow sinus, sometimes subtruncate or rounded, margin entire, lobes pointed or obtuse, apex acuminate or mucronate, palmately [3-]5(-7)-veined, reticulation conspicuously prominent abaxially. Inflorescences axillary, lax conical panicles, to 30 cm, usually shorter than 20 cm; rachis puberulent or tomentose; bracts linear-lanceolate. Male flowers: bracteoles 2, closely adnate to sepals; sepals yellowish green, abaxially puberulent, outer whorl oblong, 2-2.5 mm, inner whorl subovate, subequal to outer whorl; petals slightly fleshy, 0.7-1 mm; stamen 1.6-2 mm. Female flowers: sepals and petals as in male flower; staminodes filamentous; carpels glabrous. Drupes red to dark purple or blue-black, 5-6 mm in diam. or slightly larger. Fl. summer, fr. autumn.

Sinomenium acutum contains the alkaloid sinomenine, which is used to treat arthritis and other inflammatory conditions.

Forests. Anhui, N Guangdong, N Guangxi, Guizhou, Henan, Hubei, Jiangxi, S Shanxi, Sichuan, SE Yunnan, Zhejiang [N India, Japan, Nepal, N Thailand].