Perennial, rhizomatous aquatic. Leaves mostly dimorphic; submerged leaves if present, reduced to narrowly linear, opaque phyllodes, up to 2 mm broad; floating leaves leathery, long-petioled with a discoloured joint at the top of the petiole, ovate to lanceolate, 5-9 cm long, 3.2-4.7 cm broad; petiole up to 6 cm long. Stipules free, 5-9 cm long, persistent, linear-lanceolate. Spikes c. 4.5 cm long. Fruitlets obovoid, 3.5-4 mm long, 2.5-3 mm broad.