Nuphar advena (spatterdock or cow lily or yellow pond-lily) is a species of Nuphar native throughout the eastern United States and in some parts of Canada, such as Nova Scotia,[3][4] as well as Mexico and Cuba.

[5] Nuphar advena is a perennial, aquatic herb[5] with 5–10 cm wide,[3] spongy rhizomes.

[10] The protogynous, fragrant, nectariferous,[11] solitary,[8][6] yellow-green,[8] up to 4 cm wide flowers[3] float on the water surface, or extend beyond it.

[9][17] The specific epithet advena means immigrant,[18][10] outsider, foreigner, or stranger.

[1] It occurs in ponds, lakes, streams, rivers,[7] marshes, and swamps.

[8] The flowers are pollinated by sweat bees, syrphid flies, and leaf beetles.