Stems to 3 m. Leaves bright green, coarse textured, 1--2 × dichotomously divided; whorls 1.5--6 cm in diam.; segments linear to filiform, 1.5--2 cm × 1--5 µm, not inflated. Flowers 1--3 mm in diam. Achene dark green to reddish brown, body (excluding spines) 3.5--6 × 2--4 mm, smooth or slightly tuberculate, margins wingless and spineless, facial spines absent; basal spines or tubercles 2, 0.1--12 mm, straight or curved; terminal spine (persistent style) 0.5--14 mm. Fl. and fr. Jun--Sep. 2n = 24, 38, 40, 48.

This species is widespread throughout China and expected to be reported from additional provinces.

Streams, ponds, lakes. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jilin, Nei Mongol, Ningxia, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Xinjiang, Xizang, Yunnan, Zhejiang [Cosmopolitan].