Papilio thoas, commonly known as the Thoas Swallowtail, is a large and striking butterfly in the family Papilionidae. It is one of the largest swallowtails in the Americas. The wings are boldly patterned in yellow and black, with broad yellow bands crossing dark wings. The hindwings often show additional red and blue markings, especially on the underside, along with short tail-like projections typical of swallowtails. Its large size and high-contrast pattern make it very noticeable in flight. This species is found in Mexico, Central America, and South America, inhabiting forests, forest edges, gardens, and open areas. Adults are strong, active fliers and are frequently seen gliding or visiting flowers for nectar.