The Papilionidae belong to the Superfamily Papilionoidea, the true butterflies. Swallowtails are worldwide in distribution and comprise approximately 560 species. They are richest in the tropics, and their brilliant colors make them favorites of butterfly enthusiasts. Many swallowtail species, especially in the tropics, mimic other butterflies that are distasteful, while others are distasteful and cause birds and other vertebrate predators to regurgitate. Swallowtail adults are medium to large and may or may not have tails, while parnassian adults are medium, tailless, and have translucent wings. All adult parnassians and swallowtails have three pairs of walking legs, and adults of all species visit flowers for nectar.