Cuckoo bee Bombus sylvestris

Four-coloured Cuckoo Bee Takes over the nests of the early bumblebee
This is the best I could do. This was the only one and much bigger than other bumble bees, but it's enough to show you the difference between a cuckoo bee and other bumble bee physiques. If I can find it again I will.

Ok. I said I would go back and try to locate the Four coloured Cuckoo Bee
Well I did and and after an hous wait and a few minutes more .............ages actually.
My patience was rewarded. The red fringe at the tip of the tail you'll see in the first photo shows this is a male
Below is a much better side view and a face view.