General Description

Colours vary between the sexes, the male is almost all black on the upper side but for a red spot on each hind wing and some white patches. The female is a browner colour and her forewings are streaked with white, she also has a series of red crescents on the hind wings rather than a single spot. The undersides of the wings in both sexes have attractive blue crescents. Wingspan to 10 cm.

Biology

The Orchard Swallowtail is one of the native species, like the magpie and galah, to benefit from European settlement in Australia. The larvae are able to feed on introduced citrus plants and this species has subsequently expanded its range. This species seems to illicit either delight due to its size and beauty or annoyance from citrus growers, (and home gardeners) due to the larvae feeding on citrus leaves. The larvae show a very interesting adaptation designed to reduce their rate of predation; they resemble bird poo. This resemblance to bird poo has also evolved in the aptly named bird-dropping spider. In later instars (stages between moultings) the caterpillars are more obvious to predators, but when threatened can release an odour and evert a red osmeterium, a defensive organ that in this species resembles a pair of red horns.

Distribution

Coastal eastern Australia from Cape York Peninsula through to Adelaide, with records from central Australia, coastal Northern Territory and coastal south-west Australia.

Habitat

Large areas of eastern Australia where its food plants can be found, this may be urban gardens, rural areas or forests.

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