By Lindsey Tarkington
The green horse fly, Chlorotabanus crepuscularis Bequaert (18 mm) is the only distinctly bright yellow-green horse fly in North America. Males have large compound eyes that are touching on the front of the head; those of the female are separated by a small gap. Adults are most active at dusk and dawn in spring and summer, especially from May to July. The predaceous larvae live in wet soils in woodland habitats. Blood-feeding females find their mammalian hosts by tracking exhaled carbon dioxide. This species is widespread in moist, wooded habitats in Virginia and is found throughout eastern United States to southern Arizona.
BugGuide. Species Chlorotabanus crepuscularis. Iowa State University Entomology, 10 May, 2005. Web.1, July 2012. <http://bugguide.net/node/view/17583>
Marlos, Daniel. What’s That Bug? Horse Fly: Chlorotabanus crepuscularis. 14 May, 2011. <http://www.whatsthatbug.com/2011/05/14/horse-fly-chlorotabanus-crepuscularis/> (accessed 1 July, 2012)