I guess Lasiorhynchites cavifrons (Gyll.), but L. olivaceus might be a good ID as well. Both species are present in UK.
Thank you for your help gentlemen, getting to grips with the intricacies of the differences between species is one of the many fascinating aspects to a beginner like myself.
I should have said it was about 4mm long and was found in London on Wimbledon Common which is very near, my "home" area. I'm off to Provence for a short break at the end of the week, so I'll have to see what new experiences await!