UFO

Today, as the weather was still ideal for it, I spent some more time in the garden cutting things back. I spared some of the brambles which had blackberries on them, for the birds and insects to feed on. They're at that lovely stage where they still bear some of the delicate flowers, but also fruit at various stages of ripening.

I noticed this winged insect crawling about on one of the brambles I had left. At first I thought it was a hoverfly, but it wasn't sleek and shiny like they are, nor did it dart and flit about. Instead, it moved in a very leisurely fashion and stayed still for ages while my camera loomed over it. It didn't seem at all bothered, no matter how close the lens got. After an extensive search of the internet I'm still none the wiser. Has anyone else got a clue what this Unidentified Flying Object might be?

Here's a photo of it from a different angle.