Small amphibious herb; corm 2-lobed, 5–10 mm long. Leaves to 65, spirally arranged, erect-patent, 6–10 cm long, 0.8–1.5 mm diam., flexible, bright green; base 4–5 mm wide, narrowly winged, white, translucent; peripheral fibre strands and internal hairs absent; stomata present apically; trans-lacunar diaphragms visible; ligule triangular, 1 mm long; labium minute. Sporangia elliptic, 2.5–4 mm long, 1.5–2.5 mm wide, translucent; velum covering 5–15% of sporangium. Microspores unknown. Megaspores Types I and IIA, 0.25–0.46 mm diam.; each proximal face with 1 (rarely 2 or 3) very large tubercles; distal face with broad anastomosing wavy ridges, drying white or grey.