My guide says that these are ‘an unwelcome and attentive follower of human visitors’ – this was definitely true. There were loads of these in the Tiffey Valley in Norfolk. They kept landing on me and biting me, so I spent half my time swatting them away. This one was sat on my jeans and I took the opportunity to take the photo. Annoyingly, it actually cut through some of the threads in the denim while it was there!