Synonym: Caltha natans; Caltha pusilla.
Region: North America, East Asia, Siberia, Mongolia, north China.
Habitat: in shallow water, floating leaves.
Botany: relatively little morphological variation; leaves 2 cm wide and 5 cm long, on a petiole up to 7 cm long; flowers 5 mm in diameter, with five white sepals, with 20 to 55 follicles; blooming in late spring; seeds black, elliptic.