具刚毛荸荠 ju gang mao bi qi

Eleocharis valleculosa f. setosa (Ohwi) Kitagawa.

Perennials, with a rhizomes and stolons. Culms single or tufted, 6-50 cm tall, 1-3 mm thick, terete, with a few sharp ribs. Leaf sheaths 1 or 2, basally purplish red, tubular, 3-10 cm, mouth truncate. Spikelet oblong-ovoid to narrowly oblong-ovoid, rarely ellipsoid to oblong, 0.7-2 cm × 2.5-3.5 mm, many flowered. Basal 2 glumes empty, amplexicaul for 1/2-2/3 of spikelet base; fertile glumes greenish to pale medially and with a narrow pale blood-red band on sides, ovate to oblong-ovate, ca. 3 × 1.7 mm, margin broadly hyaline, apex obtuse. Perianth bristles 4, distinctly longer than nutlet, slightly curved and not spreading, densely retrorsely spinulose. Stigmas 2. Nutlet yellowish, globose-obovoid, ca. 1 × 1 mm, biconvex, smooth; persistent style base broadly ovoid, ca. 1/3 as long and ca. 1/2 as wide as nutlet, spongy. Fl. and fr. Jun-Aug.

Shallow water; 100-4300 m. Anhui, Gansu, Guizhou, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jilin, Liaoning, Nei Mongol, Ningxia, Qinghai, Shaanxi, Shandong, Shanxi, Sichuan, Xinjiang, Xizang, Yunnan [Japan, Korea].

Eleocharis valleculosa var. valleculosa occurs in Japan and Korea and differs by lacking perianth bristles.