This is the amazing caterpillar of the Golden Birdwing butterfly.
Seen in Kadoorie Farm. You can see it has been disturbed as it is projecting some fierce looking nodules of bright yellow and orange, that also send off a distinct scent.
There are two species of Birdwings in Hong Kong, and these are the only two butterfly species protected by law; they are the Common Birdwing and Golden Birdwing, which are visually very similar.
