I think this is the larva of an Orchard Swallowtail, but it's on a Wollemi Pine! The pine is a few metres from a mandarin tree and a lemon tree. Should I move the caterpillar to one of those trees?
Spot on again Curiosity. Just leave it where it is. This is a final instar (mature) caterpillar which may have just moved on from the food plant to pupate.