What is it?

I have at last started on a long delayed job of editing - deleting - and saving - a series of pix taken with my Sony A 350 back in 2008.

Just under 2,000 JPG's in 108 folders. Procrastination is a thief of time, as I have just realised. 

What I am doing is to whittle down the remnant of pix taken for use left in the files after the selection of pix required had been made. I have found several already that could have been edited and saved at the time.
However this one had been underexposed and was very dark. In order to see just what if was - I thought at first a piece of wood or dead leaf - I "Lightened shadows" with Elements 3 and saw that it is an insect of some sort.
I have put a request on ID Please in Flickr but wonder if it could be a Gatekeep or Meadow brown butterfly that had been caught by cow manure splash.
Answer from two people in ID Please, including Backeye. It is a Peacock butterfly Inachis io. I must try to find out why it is so splattered looking.