Picking off the citrus bugs from the orange tree, I saw this cocoon, all dried up and with a hole in the base.
Friend Christa clued me in to the correct ID – Papilio aegus, the orchard or citrus swallowtail butterfly. Thanks, Christa!
She also sent me some photos from her own garden showing one of the instars (developmental stages) and a cocoon, in much better shape than mine, that it came from.
The instars all have slightly different colours and forms, as can be seen on the Coffs Harbour Butterfly House website.
Adult males and females look slightly different.
According to the Brisbane’s Big Butterfly Count Facebook page:
… one of our largest, the Orchard Swallowtail. Many of you will have encountered this beauty and will easily recognise it. You can’t miss it just by its size. According to M. Braby the size varies from a wingspan of 102mm (male, below right) to 108mm (female, below left), some describe them as larger. The males are predominantly black with white markings while the female is very attractive with extensive white-greyish markings and additional red and blue ones on the hindwing.
Once emerged from the egg, the caterpillar (larva) looks like a bird dropping, brown and white in colour, with growth gradually changing through instar stages to a mostly green appearance before it changes into the pupa (chrysalis). The chrysalis colour can change too, depending on where it is positioned, presumably to blend into the surrounds.
This butterfly has many larval hosts. Home gardeners will find the caterpillars on citrus trees and the adult butterfly on many flowering garden plants. Among the native host plants for larvae are Lime berry (Micromelum minutum), native limes (Citrus australis, C. australasica), and Crow’s Ash (Flindersia australis).
Did you know that this butterfly’s larva (like that of other swallowtails) uses a red osmeterium to warn predators? Osmeteria look like a little forks and are located just behind the caterpillar’s head. They are everted when the larvae feel threatened.
Many gardeners consider the caterpillars to be pests on their citrus trees, but I’m happy to share. As Sir David Attenborough says, “I think sometimes we need to take a step back and just remember we have no greater right to be here than any other animal.”