Fronds 1 or 2--8 coherent together in often starlike groups, narrowly tongue-shaped to ribbonlike, 1.2--7.5 mm, 3--8 times as long as wide, rounded at tip or pointed; tract of elongated cells running along or near edge of lower wall of pouch; area of air spaces within frond much longer than wide, often spreading throughout most of frond; angle of pouch 45°--90°; flowering fronds similar to vegetative ones. Fruits 0.3--0.4 mm. 2n = 40, 42.

Flowering (very rare) throughout year. Mesotrophic, quiet waters in warm-temperate to subtropical regions with mild winters; 0--400 m; Calif., Fla., La., Miss., Tex.; Mexico; West Indies; Central America; South America.