Rhizomatous, aquatic perennial with submerged and floating leaves. Stem terete, to 4 m long; turions not recorded. Stipules convolute. Submerged leaves sessile or petiolate; blade lanceolate, 3–10 cm long, 0.5–2.3 cm wide, rounded or acute at base, obtuse or tapered at apex, 5–15-veined. Floating leaves petiolate; blade ovate to ±circular, 0.8–3.5 cm long, 1–1.5 cm wide, rounded or tapered at base, obtuse, acute or mucronulate at apex, coriaceous, 5–16-veined. Inflorescence a terminal spike, emergent, dense, to 2.4 cm long. Peduncles erect, recurved when fruiting. Fruit laterally compressed, ±circular, 2.1–3 mm long (including beak), with 3 ridges, the central one more prominent, with a prominent beak.
Home