Description: Monoecious or dioecious aquatic perennials or annuals with submerged, floating or emergent leaves.
Leaves all basal, usually differentiated into petiole and lamina except when young; lamina of mature leaves expanded; petiole with a sheathing base. Spathes unisexual or bisexual; female and bisexual spathes 1-flowered, male spathes many-flowered.
Flowers bisexual or unisexual, chasmogamous or cleistogamous. Perianth of 2 whorls, inner segments larger and petaloid, white or coloured. Stamens 6–15. Ovary 6-locular; styles 6–15, 2-fid.
Fruit an indehiscent utricle; seeds numerous.
Distribution and occurrence: World: c. 40 species, tropical & subtropical regions. Australia: 2 species (native), all mainland States.
Text by S. W. L. Jacobs
Taxon concept:
| One species in NSW: Ottelia ovalifolia |
|
