It was originally only present in New South Wales, Victoria and Queensland, but due to the growing of citrus, a larval food plant of this species, in orchards, the species spread to South Australia in the late 1920s.

Papilio anactus is not present on Kangaroo Island or elsewhere in Australia, as there are currently too few citrus trees.

Females only lay eggs on the newly grown leaves of the host plant.

Eggs normally hatch after approximately 3 or 4 days, but the duration may vary depending on the time at which they are laid.

The anterior parts have broad yellowish bands and a black head, with some short hairs; the first three instars retain this.

[3] Mature larvae are about 35 mm long, generally black, with two subdorsal rows of fleshy black spines, and sublateral and lateral rows of large orange or yellow blotches, and numerous small, light blue and white spots.

[3] When disturbed, the larvae can erect a reddish-orange coloured, osmeterium from behind the head which releases a citrus-like smell of rotting oranges.

It is usually attached to the stems of the host plant and almost always on the other side of the tree from where the larva was last feeding.

Often those pupae formed in autumn will not become adults until the following spring, or even longer with diapause records of 1 to 2 years.