Small tortoiseshell butterfly

Well known colourful little butterfly.
"dark body and red and yellow wings, which have a row of blue dots around the rear edge. However the underwings are dull, which helps to conceal stationary or hibernating individuals. When threatened, resting individuals rapidly open their wings, presenting the dramatic display of colours. This can frighten away young or inexperienced birds"
http://en.wikipedia.org/wiki/Small_Tortoiseshell