The Old World Swallowtail (Papilio machaon) is a butterfly of the family Papilionidae. The butterfly is also known as the common yellow swallowtail or simply the swallowtail (a common name applied to all members of the family). It is the type species of the genus Papilio and occurs throughout the Palearctic region in Europe and Asia; it also occurs across North America, and thus, is not restricted to the Old World, despite the common name.