Tucson Botanical Gardens, Feb 2013, Canon Powershot SX40HS
Papilio palinurus, common name Emerald Swallowtail, Emerald Peacock, or Green-banded Peacock, is a butterfly of the genus Papilio belonging to the Papilionidae family. It is native to southeast Asia, but regularly kept in butterfly zoos around the world.
Papilio palinurus has a wingspan reaching about 8–10 centimetres (3.1–3.9 in). The dorsal sides of the wings are covered by a powder of green scales and the background vary from dark greenish to black, with broad bright emerald green metallic bands. The undersides are black with orange, white and blue spots along the edges of hind wings, that show extended tails at the end.
The flight of these butterflies is swift and quite fast. Caterpillars feed on plants of genus Euodia belonging to the Rutaceae, commonly known as the rue or citrus family.
Info copied from http://en.wikipedia.org/wiki/Papilio_palinurus