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DescriptionAnnual or perennial (semi-)aquatic herb, up to 1.5 m tall. Rhizome small; roots fibrous and spongy. Leaves emergent, erect; petiole up to 50 cm long, 3-angular in cross-section. Lamina sagittate, mostly hairless, with scattered pellucid dots, wider than the length ot the midrib and basal lobes as long or longer than the mid rib; veins 13-17, 3-4 pairs arising from the base, arching to the leaf apex, the others curving down towards the tips of the lobes. Inflorescence on a stout peduncle 0.3-1 m long, branched with 4-7 whorls of flowers. Flowers bisexual or some male in the basal whorls, with greenish petals and white petals. Fruit with up to 30 carpels, forming a globose head, 10-12 mm in diameter.