I saw the black spiky caterpillar when I moved a pallet and thought I'd take a picture of it. Half an hour later I came back and it had turned green. It was on the exact spot where the black caterpillar was. It looked like it had turned to a pupa, but I thought that was an very long process.
Anyway, it will turn into a Peacock butterfly I think.
Some caterpillars spend a while spinning a cocoon but some - peacock butterflies included - simply shed their final caterpillar skin, so the chrysalis was already formed here, the caterpillar simply had to shed the black skin which probably took about 10 minutes!
A great find!