Idana marginata, the Picture-winged Fly is a very distinctive member of the Ulidiidae family. This fly has red eyes, vertically striped markings on the thorax, and horizontally striped markings on the abdomen. I don't think the point that the abdomen tapers over to is an ovipositor, I think it is supposed to mimic a stinger. As you can see in the upper right hand corner of the first photo, this fly emitted a liquid as I was handling it, perhaps a defensive mechanism.
Lifer! These awesome flies are in pretty huge numbers!
Lat: 42.35, Long: -74.02
Spotted on Jun 9, 2013
Submitted on Jun 16, 2013
and 3 other people favorited this spotting