Lepidopterologists - do you know this Moth?

My workmate, Glen Hilton, came upon this moth back in April/May 2010 last year. He had seen it upon a wall that he was cleaning cob webs from. Not wishing to harm the creature, Glen took the moth outside and put it on a tree. It was then that he called me excitedly to come out and look at his delightful discovery. 



The back of the moth looks like a pruned branch cut in this photo-below branch



I have to admit that I was very pleasantly surprised also. That is to say, when I finally realised what I was looking at. Glen kept telling me there was a moth on the tree, but I could not make the creature out because it was so well camouflaged. As the moth stood motionless on the thin tree branch, it looked like a small broken twig that had been pruned. When I did finally make it out, I was stunned.



The light part is the rear of the moth's wings. On the twig, it looked pruned.



We were studying the moth for some time and this caused an inquisitive neighbour to come out and enquire what we were  looking at. When we drew the ladies attention to the moth, her reaction was the same. We began to photograph it with the mobile and are wondering if any person interested in lepidopterology would know what type of moth it is. We live in United Kingdom, England, Essex and have never seen the like before. Does anyone know the species?   



When I first starred at the branches, I could not make out the moth





Does anyone know this species of moth?



I have never seen a moth like this in Essex, UK. Is it rare in this part of the country?