#1
Well, familiy level would be OK, everything below a bonus! I saw these copulating flies in Amstelveen, the Netherlands, on 18 April 2007 (they may be really early, because that April was HOT by Dutch standards).
Medium sized, some 5 - 7 mm. Habitat: playing ground grass land surrounded by shrubs and medium sized trees.
May be
Ophyra?? Any better suggestion is welcome!