The pipevine swallowtail has a wingspan of two and three-fourths to ﬁve and one-eighth inches. Its wings and body are black. The hindwings are iridescent green-blue on the upper side and have a projection from the back edge. Each hindwing has a row of seven orange spots that can be seen on the underside. The larva is brown or black with ﬂeshy projections, two rows of which on the back are orange or red.
The pipevine swallowtail may be found statewide in Illinois woodlands where pipevine plants are present, although it is not abundant. The larva and adult are bad tasting to birds and can actually cause birds to spit them out after being eaten. This trait helps birds learn to avoid them. Several other butterﬂies are colored and shaped similar to the pipevine swallowtail, and birds are reluctant to eat them, too, even though they have none of the distasteful chemicals. The pipevine swallowtail reproduces twice each year. The caterpillar has yellow or red structures that can be extended from behind the head when it is threatened. The pupa is protectively colored. This insect overwinters in the pupa stage. The adult feeds on nectar, ﬂapping the wings rapidly as it does so. The larva eats plants, particularly snakeroot and pipevine.