Superb shot - very well done - that MP-E65 is an incredible piece of work but how do you get the depth of field? What flash system are you using?
I am guessing that the mites are phoretic - hitchhikers, rather than parasites. I see them a lot of samples of neotropical Hymenoptera and Diptera, all clustered together and holding on for dear life.
The "chalcid" might be a chalcid but it isn't common to see all-black ones so it could be one of the other groups - not sure. Did you get any dorsal shots?
