Free-floating aquatic with many long purple feathery roots which may anchor the plant in mud around edges of ponds, streams, etc.; stolons many, thick, fleshy, radiating in all directions, producing leafy tufts which readily separate and form new plants. Leaves bright green, smooth, leathery; laminae to 8 cm wide, ovate to orbicular, many-nerved; petiole usually inflated below, spongy and bladder-like. Flowers to 7 cm diam., bluish-purple, 8-10, spirally arranged in a terminal spike; scape to ± 20 cm high with leaf-like bract; tube green; lobes blue-purple, uppermost widest with a deeper blotch containing a bright yellow spot. Capsule membranous, 3-celled, many-seeded, enclosed in withered perianth. Seeds small, ovoid, ribbed.