Rhizomes erect or ascending, unbranched. Leaf blade suborbicular, 10--25 cm in diam., papery, abaxially glabrous, scarcely peltate, base deeply cordate and basal lobes contiguous or overlapping, margin entire. Flower floating, (6--)10--20 cm in diam. Calyx insertion on receptacle ± tetragonous; sepals lanceolate, 3--5 cm, obscurely veined, caducous or decaying after anthesis. Petals 20--25, white, ovate-oblong, 3--5.5 cm, transition to stamens gradual. Filament of inner stamens wider than anther; connective apically unappendaged. Carpels completely united, walls between locules of ovary single. Stigma rays (5--) 6--14(--20); carpellary appendages triangular-tapered. Fruit semiglobose, 2.5--3 cm. Seeds ellipsoid, 3--4 mm, smooth. Fl. Jun--Aug. 2n = 112, 160.

Ponds. Xinjiang [Kashmir, Kazakhstan, Russia (Siberia); SW Asia, Europe].