Window Fly

Large ant/wasplike bug with transparent section of abdomen
Location:  Cambridge, MA
September 12, 2010 4:50 pm
We found this bug in our apartment in Cambridge, MA, a couple of days ago. Behaviorally, it was very attracted to light, much like a fly, but is shaped very strangely for a fly. The body is about 3/4 inch long. Once we got a good look, we also noticed that the top section of the insects’ abdomen is completely transparent! Very strange!
Any idea what this could be?
Signature:  Adena

Black Soldier Fly, AKA Window Fly

Hi Adena,
Though BugGuide refers the common name Window Fly for members of the family Scenopinidae, Charles Hogue in his book Insects of the Los Angeles Basin calls the Black Soldier Fly,
Hermetia illucens, a Window Fly because of the clear areas in the abdomen.  According to BugGuide it is a:  “Large soldier fly, all black with bright white tarsi. Underneath, first abdominal segment has clear areas. Wings have purplish sheen. Likely a wasp mimic, it buzzes loudly. In particular, it appears to mimic the Pipe-organ mud dauber…“.

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