Botanische Jahrbucher fur Systematik, Pflanzengeschichte und Pflanzengeographie 21: 303. 1895.
Fronds 1 or 2–4 coherent in small groups, wide tongue-shaped or ovate, 3–9 mm, 1.5–4 times as long as wide, rounded at tip; tract of elongated cells running between median line and edge of lower wall of pouch; area of air spaces within frond rarely longer than wide; angle of pouch 70°–120°°; flowering fronds narrower than most vegetative ones. Fruits 0.41–0.44 mm. 2n = 40, 42.
Phenology: Flowering (very rare) throughout year.
Habitat: Mesotrophic, quiet waters in subtropical to tropical regions with mild winters
Elevation: 0–200 m
Calif., Fla., La., Tex., Mexico, West Indies, Central America, South America.