Aquatic, submerged plant, mostly monoecious, rarely dioecious. Leaves simple, thin, blades lanceolate to widely ovate or cordate-reniform, to 17 × 20 cm, entire to crisped. Inflorescence 1-flowered, with spathes winged, 3–10. Flowers emerge at water surface; sepals 10–15 × 2–9 mm; petals obovate with rounded apex, white or spotted, yellow at base, 2–3 cm long; stamens 3–12, filaments with glandular hairs; anthers basifixed, linear, 3–4 mm long; carpels 3–9. Fruit oblong-elliptic, rostrate, crowned by persistent calyx, dehiscing irregularly. Seeds fusiform, 1–2 mm long.

Common weed in lakes, streams, ditches, rice paddies, and permanent pools, at elevations from near-sea level to 1200 m a.s.l. Propagated by seed sowing or sucker separation.
Young leaves and flowers are harvested year-round and eaten raw with nam phrik (dipping sauces) or as a side dish.