Botanische Jahrbucher fur Systematik, Pflanzengeschichte und Pflanzengeographie 21: 303. 1895.
Roots absent. Fronds submersed (except when flowering or fruiting), proximal part near surface, 1 or 2–20 or more, coherent, linear, ribbon-, sabre- or tongue-shaped, or ovate, flat, longer than 2 mm, margins entire; air spaces in tissue; pouch 1, terminal, at base from which daughter fronds (no flowers) originate, triangular, lower wall of pouch with tract of elongated cells forming connection between node and attachment to mother frond; veins 0; scale at base of frond absent; anthocyanins absent; pigment cells present (visible in dead fronds as brown dots); turions absent. Flowers 1(–2) per frond, originating in cavity at side of median line of upper frond surface, not surrounded by utricular scale; stamen 1, 2-locular. Seeds 1, nearly smooth. x = 10, 20, 21.
North America, West Indies, Central America, South America, Africa.
Species 10 (3 in the flora).
|1||Fronds (4–)6–15(–20) times as long as wide; angle of pouch 25°–50°.||Wolffiella gladiata|
|1||Fronds 1.5–8 times as long as wide; angle of pouch 45°–120°.||> 2|
|2||Angle of pouch 70°–120°; 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.||Wolffiella lingulata|
|2||Angle of pouch 45°–90°; tract of elongated cells running along or close to edge of lower wall of pouch; area of air spaces within frond mostly longer than wide.||Wolffiella oblonga|