The flies
of this family are widely distributed throughout the world. Mostly
in the cooler climates or temperate zones of both the Northern and
Southern Hemispheres. (Oldroyd, 1965) Abundant worldwide. Larvae
are found in all fresh water, semi- aquatic, and moist terrestrial
environments. http://www.niles-hs.k12.il.us/North/Science/bragre/diptera.html#where
II.