Eastern Tiger Swallowtail (female)

"It is one of the most familiar butterflies in the eastern United States, where it is common in many different habitats. The male is yellow with four black "tiger stripes" on each fore wing. Females may be either yellow or black, making them dimorphic. The yellow morph is similar to the male, but with a conspicuous band of blue spots along the hindwind, while the dark morph is almost completely black." ~wiki