Heteranthera peduncularis

Plant: annual aquatic herb; vegetative stem submersed with elongate internodes or emersed and procumbent Leaves: few, submersed, thin, whitened on abaxial surface, linear to oblanceolate, the apex acute; petiolate leaves floating or emersed, 3-7 cm long, cordate, the apex acuminate INFLORESCENCE: a spike with 7-17 flowers; peduncle glabrous, 7-15 cm long Flowers: perianth salverform, mauve or white, the tube 3.4-6.0 mm long, the lobes narrowly elliptic, acuminate at apex, 3.2-4.8 mm long, the upper central lobe dark purple at base; stamens of two sizes, the laterals 1.4-2.5 mm long, with yellow oblong anthers 0.6-1.1 mm long; central stamen 2.0-3.4 mm long with an oblong, yellow anther 0.9-1.6 mm long Fruit: an elongate capsule with longitudinal dehiscence. SEEDS many, 0.6-1 mm long, the testa with longitudinal wings and cross striae between wings Misc: ditches and ponds; above 900 m (2700 ft) REFERENCES: Horn, Charles N. 1998 Pontederiaceae. J. Ariz. - Nev. Acad. Sci. 30(2): 133.