泽薹草 ze tai cao

Alisma parnassifolium Bassi ex Linnaeus, Syst. Nat., ed. 12, 3: 230. 1768; A. parnassifolium var. majus Micheli; A. reniforme D. Don; Caldesia parnassifolia var. major (Micheli) Buchenau; C. reniformis (D. Don) Makino; Echinodorus parnassifolius (Bassi ex Linnaeus) Engelmann.

Rhizomes creeping. Petiole 5-100 cm; leaf blade ovate or elliptic, 2-10 × 1.5-7 cm, veins 9-15, base cordate to deeply so, apex obtuse. Scapes erect or not, 30-125 cm high; inflorescences paniculate, 20-35 cm. Flowers 3-verticillate; pedicels 2.5-4 cm. Sepals persistent, ovate, 3.5-5 × 2-3 mm. Petals ovate, larger than sepals. Stamens 6. Carpels 5-10, laterally compressed; style 2(-4) mm, slender. Fruitlets obovoid, ca. 3 × 2 mm, with 3-5 longitudinal ribs abaxially and an erect beak. Fl. and fr. May-Oct. 2n = 22*.

Lakes, ponds, marshes. Heilongjiang, Hunan, Jiangsu, Nei Mongol, Shanxi, Yunnan, Zhejiang [India, Japan, Korea, Nepal, Pakistan, Russia, Thailand, Vietnam; Africa, Australia, Europe].