Pontederia rotundifolia
Content
Description
Annual or perennial. Vegetative stem elongate, floating or on mudflats; flowering stem to 26 cm long, the lower internode procumbent or erect. Sessile leaves not seen; petiolate leaves floating or emersed, reniform to cordate, obtuse to acute at apex, 3-12 cm long, 3-22 cm wide; petiole glabrous, 7-50 cm long. Stipules 5-17 cm long. Inflorescence with 3-25 flowers; peduncle pilose, 1.4-5 cm long; spathe 1.6-4.5 cm long. Flowers pilose, tube 4-8 mm long, tepals blue or white, 7-12 mm long, the central upper tepal with 2 yellow spots near the center; lower stamens 0.7-8 mm long, upper stamens 6.5-14 mm long, anthers ovoid to oblong, 0.6-1.3 mm long, larger on the longer stamens; ovary 1-2 mm long; tristylous. Nutlet about 7 mm long, including apical attenuate spine.