This perennial aquatic herb is characterized by rhizomatous and stoloniferous growth. Its leaves are broadly ovate-elliptic or reniform to orbicular, with margins that are repand to spinous-dentate. The upper surface of the leaves is dark green, glabrous, and often pustulate, while the lower surface is green or dull purplish-green and velutinous pubescent. The flowers are large, slightly fragrant, and white, borne on long peduncles.