Whilst processing some of my recently taken butterfly images I found these taken of a Marbled White (melanargia galathia) that had quit a few red parasites attached.
I've seen butterflies with these parasites before but didn't really know what they were or what affect they may have had on their butterfly host. A little bit of research and I soon came up with some interesting information....
trombidium breei is the name of this particular mite that attaches itself to mainly the males, (but in these images they are attached to a female!) of Meadow Brown, Common Blue, Small Skipper and the Marbled White butterflies. While attached it feeds on the blood of its host and will normally drop off after a few days. It can also transfer from host to host as they congregate on their food plants.
Incredibly they know how to attach themselves onto the area of the butterfly's centre of gravity (around the underside of the head) or longitudinally along the abdomen so as not to upset the butterfly's orientation or its ability to fly!
The good thing is that the butterfly appears to suffer no ill effects which, I guess, is a way of the parasite ensuring that there will be a good supply of hosts for next year!