The Black Swallowtail Papilio polyxenes #4159 is a black butterfly with spotting around the edge of the wing. The male has 2 rows of yellow spots around the topside of the wings. The female has smaller spots and a few blue spots on the topside of the hindwings. The underwing has a pattern of orange, blue and yellow spotting. on a black wing. The Black Swallowtail favors plants in the carrot family like parsley for its host plant and visits a variety of plants for nectar.