Description: Aquatic or amphibious plants with a persistent, swollen root-stock (corm).
Leaves simple, crowded at the apex of the root-stock, ± terete or linear with broad, spoon-like bases. Most leaves act as sporophylls.
Sporangia embedded in the expanded basal part of the leaf, of 2 different kinds and giving rise to different sized spores.
Distribution and occurrence: World: 2 genera, c. 100 species, tropical to temperate regions. Australia: 1 genus, 15 species, all States.
Text by Peter G. Wilson
|One genus in NSW: Isoetes.|