#1
It took me quite some time to figure out to even what family this fly might belong - actually in the end it was pure luck: Had an initial (
wrong) suspicion, so I fetched Marshall's awesome 600+ pages of 'Flies' to check images of that family, opened the book randomly - and stared at a Mythicomyiid fly! Immediately knew that is the right one
Never heard of that family before, but I guess, although not in the Gallery, that there is no other option than
Glabellula arctica?
It looks like the female is ovipositing, but the larvae develop in
Formica nests, so not sure what it is doing...
Cheers, Lorin