刺苦草 ci ku cao

Rhizome tuberous; stolons with minute spines. Leaves 20-50(-200) cm × 4-10 mm, midvein prominent, with 1 row of minute spines, margin serrulate, apex obtuse or slightly acute. Male spathe conic, 1-1.5 cm × 5-8 mm, with more than 300 male flowers; sepals convex; petals 2, connected at base of filaments; stamens 2, filaments without hairs. Female spathe 1-2 cm, with very long slender peduncle; sepals ca. 4 × 2 mm, apex obtuse; petals minute; staminodes 3. Fruit triangular-cylindric, 8-20 cm × 4-7 mm, with spines on angles. Seeds obovoid, 2-5-winged. Fl. and fr. Aug-Oct. 2n = 20*.

● Ponds, lakes. Guangxi, Hubei, Hunan, Jiangsu.