Ornithoptera priamus is sexually dimorphic. Male: The upperside forewings are velvety black. There is a green subcostal stripe and a green marginal stripe bordering the termen, tormen and dorsum of the wing. The sex brand is black and longish. The underside of the forewing is black. There is a chain of bluish or green postdiscal spots. The hindwings are green. At the wing's leading edge there are basal yellow-gold spots. There is also a postdiscal chain of black spots. The edge of the hindwing is black. The underside is dark green or bluish. The yellow-golden spots are transparent. The veins are partly black and the marginal edge of the wing is black. At the outer edge there is a postdiscal chain of black spots. The body is yellow. Head and thorax are black. The underside of thorax has a red hair coat. Female: The female is larger than the male and in the upper range of the wingspan. The basic colour of the female is dark brown. There is a chain of white postdiscal spots on the forewings. There is a chain of larger white postdiscal spots with dark centres on the hindwing. The underside is very similar to the upper. Larva: First instar larvae are wine red on hatching. They soon turn black or dark brown. All segments have soft tubercles with stiff ends bearing black spines. On the 4th segment tubercles are red. The tubercles are dark brown on the other segments. In the second instar, the tubercles lack spines, the 4th tubercles are light red and on the other segments they are the same colour as the body. In the third instar, there is a white to pink saddlemark on the 4th segment. In the fourth and fifth instars, the ground colour is ashy grey to brown, the saddlemark on the 4th segment is white and the tubercles on the 4th segment are white. There may be saddlemarks on the 5th segment and the 6th segment. The tips of the tubercle are black and the osmeterium is dark red. Pupa: The pupa is yellowish green or brown and is marked with greyish veins as in a leaf. It may have a broad dorsal pale saddle mark. The abdomen has eight pairs of sharp dorsal processes, directed laterally.
Variation
Ornithoptera priamus is a variable species. It was originally described from SeramIsland of Indonesia. As in other species of the genusOrnithoptera, the females are larger and less vividly coloured than the males, them being mainly blackish or dark brown with patterns in pale brown, yellow or white. Nonetheless, females are extremely variable, and they may have colour patterns similar to females of other Ornithoptera species. In males, iridescent areas of the wing are typically green, although some subspeciesendemic to island groups east of New Guinea have blue males. These subspecies are O. p. urvilleanus, O. p. miokensis, and O. p. caelestis. However, it is likely that O. p. miokensis is actually a hybrid between O. p. urvillianus and O. p. bornemanni from the neighbouring islands of New Britain and Bougainville. Specimens of this subspecies are variable, and can be identical to specimens of either parent, or intermediates. Immigration may also explain its rarity, as Mioko is a small island and, as of 2001, its host plants had been reduced to a few Aristolochia tagala vines growing in a local village. Several species currently recognised as distinct have previously been considered subspecies of O. priamus by different authors. These are: O. aesacus, O. croesus, O. euphorion, and O. richmondia. The last two are still regarded as subspecies of O. priamus by some.
Subspecies
There have been as many as 99 subspecies described, with many more named variants and forms described for both sexes. Some list as few as six subspecies, but a taxonomic review is needed and most recognise more:
O. p. urvillianus – New Ireland and Bougainville, Papua New Guinea, and Solomon Islands
Conservation
Overall this species remains widespread, but some subspecies are threatened by habitat destruction, with those endemic to smaller islands of greatest conservation concern. Like all birdwing butterflies, O. priamus is listed on CITES appendix II, which restricts international export to those in possession of a permit.
