Contemporary Circumscription Compared with A Utah Flora 4th ed.

Bio430

Marsileaceae

No differences at the family level.

Key Features

Leptosporangiate aquatic ferns rooted in mud with fonds that are narrow and grass-like or with 2 or 4 pinna at top of a long stipe.  Pinna are circinate.  Heterosporous, with spores developed within a hard, bean shaped sporocarp that has both micro- and megagametophytes in the same sporocarp.  Megasporangia produce just 1 spore, microsporangia produce 16-64 spores; both sporangia lack an annulus.