(Iphiclides marcellus, Graphium marcellus, or Papilio marcellus), large, familiar North American swallowtail butterfly of the family Papilionidae (order Lepidoptera), similar to the related European scarce swallowtail (I. podalirius). Wing patterns of both species are reminiscent of a zebra's stripes, with a series of longitudinal black bands forming a pattern on a greenish white or white background. There are several generations in a single year, spring broods being rather smaller than summer broods. Adult forms that emerge at different seasons vary considerably in their markings. The span of the forewings is 6 to 9 cm (2.5 to 3.5 inches); the hindwings bear streamers 15 to 25 mm (0.6 to 1 inch) long. The principal food plant of the larvae is the pawpaw.