Eye Gnats
Hippelates / Liohippelates ? sp.
Photo taken in the Superstition Mountain Wilderness, Arizona, USA. May 2009. The most common species are shiny black and only 2-3 mm in length. Eye gnats of several genera can be found in the Sonoran Desert at various times of the year.
Chloropidae -- Frit Fly Family
As immature maggots of these small flies live mostly obscure lives inside the stems of grass or other plant tissue. However, as adults their annoyance can be almost unbearable. In the Sonoran Desert they emerge in great abundance in well vegetated areas come April and May. They require salts and moisture for the development of their eggs and they obtain them especially from mammals, including human trekkers. With great persistence they enter the eyes, ears and mouth and begin immediately at lapping the sensitive surfaces with their proboscises. Many a hike has been terminated due to these insects. Although these flies can transmit eye infections, normally their activities are not harmful and they do not take blood.