Botanisk Tidsskrift 24:260, fig. s.n. [p. 261]. 1902.
Rhizomes with 2 scales at each node. Erect stems absent. Leaves apparently attached to rhizome, 10–25 × 3–6 mm; blade oblong-elliptic, base cuneate, margins serrulate, apex obtuse to rounded, pubescent. Inflorescences: spathe enclosing both staminate and pistillate flowers. Flowers unisexual, staminate and pistillate on same plants; staminate flowers deciduous shortly after anthesis; pistillate flowers nearly sessile, 2 mm. Fruits ovoid. Seeds ca. 0.2 mm.
Phenology: Flowering winter–spring.
Habitat: Sandy substrates of marine waters
Elevation: -30–0 m
Fla., West Indies, Central America (Panama, Costa Rica), South America (Venezuela, Colombia), Asia, Australia.