Stylophorum diphyllum

Stylophorum diphyllum, commonly called the celandine poppy or wood poppy, is an herbaceous plant in the poppy family (Papaveraceae). It is native to North America, where it is found in the eastern United States and Ontario. Its typical natural habitat is moist forests over calcareous rock, particularly in ravines. It is occasionally cultivated for its bright yellow flowers. The common name is derived from greater celandine (Chelidonium majus), a closely related European plant with similar flowers and leaves. ...read more on Wikipedia.