A parasite wasp that I found in a plastic tub containing a dock leaf with a leaf mine that had been left for a few months. The wasp was particularly fragile and lost one of its legs and one of its antennae when I handled it (and the other antenna may have originally been longer than shown here). I am not sure whether it is an ichneumon or a braconid wasp.
The wasp had apparently hatched out of one of the fly puparia that had been opened at one end:
Here is a close-up of the head of the wasp
And here is a side view of the body and legs:
The leaf mine that this hatched from was originally collected in Whiteknights Park, Reading, UK, on 2013-06-23.