Hybomitra sp.

This is a horse fly, probably in the genus Hybomitra. The larvae are mostly predators of other insects and live under ground. Adult horse flies and deer flies can deliver painful bites and are primarily diurnal. Horse flies and deer flies are not generally host specific. However, adults have been shown to prefer feeding on darker colored hosts because of the light polarizing and heat absorption properties that the darker coats possess. 

Order: Diptera
Family: Tabanidae
Species: probably Hybomitra sp.

Photograph: © 2012 RKD Peterson
Date of Photograph: 24 July 2012
Location: Montana, Gallatin Co.