It's pretty straightforward - as they used to say on Catchphrase "say what you see"

It's a chaser and has 4 spots, so it's a Four Spotted Chaser (yes, i know it's got 8 spots, don't confuse the issue

).
Anyway here's a good link for you Cathus
http://www.british-dragonflies.org.u...spotted-chaser
Great shot, by the way. Have you got a larger version to look at?
All the best, Sie