As I was interested in what it was I put it back in the log where it came from and when it turned into a pupae I collected it and put it in a jar. It's finally changed and I think it's an Angel Shades moth...
Hi Duncan,
The site where you found that picture might be interested in where you found that larva. I was never aware that this species fed on wood. So as it is clearly 'Angle-Shades' either it was a larva in its final 'instar' looking for somewhere to pupate, or they have an alternative food source.
The Lime-Hawk moth looks very similar by the way, but is much bigger than this, and the caterpillar is also much different.
