The caterpillar of the Copper Underwing moth is large and green although the adult moth is brown.
It has small yellow spots all over and a white and yellow line along the sides.
The teeth
The caterpillar makes a cocoon of leaves to protect its vulnerability (and/or modesty). The leaves later fall to the ground.
The pupa starts off bright, jelly green but soon turns light, then dark, brown. The caterpillar's cast off skin is seen at the end of the pupa.
This would appear to be a Copper Underwing caterpillar at an earlier age than those further above. It may, however,
be a Svensson's Copper Underwing (Amphipyra berbera) since the faint whitish (with dark rather than yellow) flank line is continuous
through the 2nd and 3rd body segments.