Description: Semiaquatic ferns; rhizome creeping, often branched, covered with hairs.
Sterile fronds either with 4 or 2 leaflets at the apex of a stipe or filiform, vernation circinate.
Sori borne within a thick-walled, nut-like sporocarp, presumed to have arisen from the inrolled lamina; sporangia bearing spores of two kinds.
Distribution and occurrence: World: 3 genera, c. 66 species, widespread. Australia: 2 genera, 9 species, all States.
Text by Peter G. Wilson
| ||Key to the genera|| |
|1||Sterile fronds with 4 cuneate to fan-shaped leaflets||Marsilea|
|Sterile fronds filiform, lacking leaflets||Pilularia|