Description: Dioecious aquatic perennials with submerged leaves and floating flowers.
Leaves more or less alternate, irregularly arranged or rarely whorled; margins toothed or entire.
Flowers axillary, solitary. Hypanthium thread-like in female flowers. Perianth of 2 ± similar whorls, the inner segments slightly broader. Male spathes with numerous flowers; separating when in bud and rising to the surface, opening when free-floating; stamens 3, staminodes 3, larger than the stamens and functioning as sails. Female spathes with 1–3 flowers; female flowers with 3 staminodes; ovary 1-locular; styles 3, 2-fid.
Fruit a capsule; seeds numerous.
Distribution and occurrence: World: c. 16 species, Africa & Madagascar. Australia: 1 species (naturalized).
Text by S. W. L. Jacobs
|One species in NSW: Lagarosiphon major|