1279

 Hydrocharis dubia (Blume) Backer

Synonym	:	Boottia renifolia Merr.
Family	:	Hydrocharitaceae
Local name	:	English-Frog-bit
Flowering and fruiting period	:	August-October
Distribution	:	China, Japan, Korea, Indian subcontinent, SE Asia, New Guinea, Malaysia
Habitat	:	Ponds and slow-running water courses, rivers
Uses	:	Used in folk medicine. Plants are cultivated in fish ponds as water cover
Key botanical characters: Leaves floating or sometimes emerged; blade cordate or orbicular, 5-7-veined, base cordate, apex rounded. Male flowers 5 or 6 in spathe; peduncles 0.5-3.5 cm; pedicels 5-6.5 cm; sepals ca. 6 × 3 mm; petals yellow, ca. 1.3 × 1.7 cm; stamens 12, inner 3 stamens staminodal; anthers 1-1.5 mm; staminodes hairy at base and papillose at apex. Female flowers larger than male flowers; sepals ca. 1.1 cm × 4 mm; petals white, yellow at base, ca. 1.5 × 1.8 cm; staminodes 6; glands 3, reniform; styles ca. 4 mm, with dense glandular hairs. Fruit berrylike, spherical to obovoid, 8-10 mm, ca. 7 mm in diam. Seeds gradually acute toward apex.