Common Name: MOSQUITO FERN FAMILY
Habit: Plant free-floating or stranded on mud, generally 1--5 cm, often fan-shaped; roots pendent from stem forks, unbranched. Stem: forked repeatedly or pinnate, thread-like, easily fragmented at joints. Leaf: alternate, in 2 rows, sessile, often overlapped, 0.5--1.5 mm, seemingly paired but actually of 2 +- round to ovate lobes; upper lobe floating or emergent, thick, +- green or +- red, margin +- white, adaxial surface smooth or generally with papillae; lower lobe submersed, generally +- larger, thinner, +- white. Sporangia: in seemingly axillary cases of 2 kinds, cases generally in pairs of 1 kind. Sporangium Case: 1.2--2 mm diam, spheric; tip dark-pointed; wall transparent; sporangia generally 20--100+, long-stalked; spores 32 or 64, spheric, in generally 3--6 barbed masses. Male Sporangium Case: 1.2--2 mm diam, spheric; tip dark-pointed; wall transparent; sporangia generally 20--100+, long-stalked; spores 32 or 64, spheric, in generally 3--6 barbed masses. Female Sporangium Case: 0.2--0.4 mm diam, hemispheric or spheric; tip obtuse, covered by dark, conic, spongy structures that aid in flotation; wall +- opaque; sporangium 1, sessile; spore 1, spheric.
Genera In Family: 1 genus, +- 6 species: +- worldwide. Note: Barbs evidently on neither sporangia nor spores, but on cells surrounding spore masses. If Salvinia is included in the same family with Azolla, as is sometimes done, the name for the inclusive family would be Salviniaceae.
eFlora Treatment Author: Alan R. Smith & Andy Murdock
Scientific Editor: Thomas J. Rosatti.