From the flood of responses it was clear that everybody apart from me knew that it was a lacewing larva. One correspondent stated that it was one of the brown lacewings as the green ones don't have the assorted detritus on their back.
The following day I went to look for a new plant for me, and this time I could identify it. There were a number of Henbane plants growing in a game cover strip in an arable field near Up Marden. I managed to squeeze records from two tetrads.
|St Dabeoc's Heath|