Description: Rooted aquatic perennials with submerged, floating or emergent leaves.
Leaves linear and without a petiole-like stalk or the stalk present and the blade elliptic to ovate with entire or sagittate bases.
Inflorescence spike-like, the 2 spathes dissimilar, the lower leaf-like, the upper bract-like. Flowers zygomorphic, tristylous. Perianth lobes 6, glabrous or glandular-hairy, fused for about half their length then divided into 2 lips, blue; upper lip 3-lobed, fused for half their length, the middle lobe broader with a yellow spot; lower lip of 3 lobes free to the top of the tube. Stamens 6, of 2 different lengths. Ovary of 3 carpels, 2 aborting.
Fruit a 1-seeded nutlet.
Distribution and occurrence: World: c. 5 species, North & South America. Australia: 1 species (naturalized).
Text by S. W. L. Jacobs
|One species in NSW: Pontederia cordata|