川蔓藻 chuan man zao

Ruppia maritima subsp. rostellata (W. D. J. Koch ex Reichenbach) Ascherson & Graebner; R. rostellata W. D. J. Koch ex Reichenbach.

Stems elongated, densely branched. Leaves 2-10 cm × ca. 0.5 mm, with conspicuous midvein, apex acuminate or acute; sheaths 2-10 × ca. 0.4 mm. Spikes 2-flowered, 2-4 cm; peduncles filiform, shortly accrescent after anthesis. Anthers elliptic. Carpels 4-6. Fruitlets obliquely ovoid, ca. 2(-3) × 1.5 mm, beak ca. 0.2 mm, with a stalk 0.5-1.7 cm. Fl. and fr. Apr-Jun. 2n = 20, 40.

Brackish water. Fujian, Gansu, Guangdong, Guangxi, Hainan, Jiangsu, Liaoning, Qinghai, Shandong, Taiwan, Xinjiang, Zhejiang [widely distributed in brackish waters of temperate and subtropical regions worldwide].