水菜花 shui cai hua

Boottia cordata Wallich, Pl. Asiat. Rar. 1: 52. 1830; B. heterophylla Merrill & F. P. Metcalf; Ottelia heterophylla (Merrill & F. P. Metcalf) T. L. Wu.

Leaves dimorphic; submerged leaves narrowly elliptic to ligulate, 30-60 × 4.5-10 cm; floating leaves broadly lanceolate or oblong-ovate, 10-20 × 4-10 cm, base cordate, apex acute to acuminate; petiole 30-120 cm. Flowers unisexual. Spathe oblong-ovate, 3.5-8 × 1.5-2 cm, with 6 longitudinal ribs, bifid at apex. Male spathe with 10-30 male flowers; sepals yellowish; petals white, obovate, 2.5-4.5 cm; stamens 12; filaments densely hairy; anthers ca. 6 mm; staminodes 3; reduced pistil 1; glands 3. Female spathe with only 1 female flower; perianths similar to male ones; ovary oblong, with 9-15 carpels; styles 9-18, papillate, bifid at apex; staminodes 3-8; glands 3. Fruit oblong, 4-4.5 × 1.6-2 cm. Seeds fusiform, ca. 1.5 mm, smooth. Fl. May. 2n = 22.

Ponds, channels. Hainan [Cambodia, Myanmar, Thailand].