I live in Cairns and have many Cairns Birdwing Butterflies in my garden. I have a vine growing over my Callistimon and was wondering if it was a Pararistolochia praevenosa.
There's a number of Pararistolochia species that the Birdwing Butterfly larvae feed on but the leaves have a distinctive midrib and the main lateral veins are spaced along it. That's unlike your leaves where all the main veins radiate out from the petiole.
tropicbreezent
celiahydeOriginal Author