Swallowtail butterflies are large, colorful butterflies in the family Papilionidae, and include over 550 species. Though the majority are tropical, swallowtails inhabit every continent except Antarctica. The family includes the largest butterflies in the world, the birdwing butterflies of the genus Ornithoptera. This Zerynthia rumina butterfly, also known as the Spanish festoon, was photographed in Extremadura, Spain.Photograph credit: Charles J. Sharp