Stems 1–2 mm diam. Submerged leaves c. 6–7 cm across when evenly spread, 3–7 times divided, segments terete, all but primary divisions usually dichotomous; petioles to c. 2 cm long; floating leaves not observed. Perianth segments 5–10 mm long, dark reddish-black or purplish; stamens 6, filaments c. 4 mm long; carpels usually 3, ovules usually 3 per carpel. Fruit with recurved pedicel. Flowers Apr.
VRiv, GipP, Strz. Also naturalised NT, Qld, NSW. Common aquarium plant which has become naturalised in Lake Nagambie and in a farm dam near Foster.
