Caterpillar

I spotted this fat caterpillar on the kitchen top chomping through some sweet potato cuttings I had for planting. By the end of today only a few small leaves remain. Close up it does not look like it is active and yet in a few minutes it has consumed quite a large portion of a leaf

The head is at the left end and the spike as at the bum end...the black lump a continuous growing and dropping "poo"

I hope I can be around with a camera when it is evolving into a moth or butterfly - I have not identified it yet.