Ommatius sp. ♂.
 
 
 
Photo: 05/07/17, noon.


The genus has 13 species in North America and over 300 worldwide. I found this one on our window frame and admittedly it looked rather dead or perhaps it was just taking a break from the stressful life of being a robber fly. 
 
 
bug guide (this photo):
http://bugguide.net/node/view/1365920