Cairns Birdwing Butterfly

From Wikipedia:

The Cairns Birdwing (Ornithoptera euphorion) is Australia's largest endemic butterfly species, with females reaching a wingspan of up to 16 cm. Males are usually a few centimeters smaller. A closely allied species, the New Guinea or Priam's Birdwing (Ornithoptera priamus) reaches 19 cm and is the largest butterfly species found in Australia, but it is not endemic. Cairns Birdwings are found southwards from Mount Webb and Cooktown to Mackay in Queensland. Favoured habitat is primary rainforest, although the species will breed readily in a home garden if the correct larval host plants are grown