Blackthorn Bee-fly

Another lovely spring day. I managed to get a bee-fly hovering as it supped from the blackthorn with its long proboscis. These insects look like bees but are parasitic flies which flick their eggs into the nests of mining bees.  

A beautiful male brimstone butterfly fluttered quickly past. They don't stop to rest at this time of the year as they have one thing on their minds. A peacock butterfly stopped for some nectar. When I looked at my image of it on screen I could see that it had tiny, light-coloured mites on its wings. (Extras) I've seen insects with the odd red mite but I've never seen these on a butterfly before.