Snipe Fly
"Rocky Mountain Bite Fly"

genus Symphoromyia

snilpe fly
While we were enjoying the view from the mountains above Strawberry Reservoir, these nasty little flies
were biting our legs and it hurt like *!#!.  I slapped this one silly and then ground it into the dirt. I propped
it up for these photos and, to my surprise, the dang thing still wasn't dead.  Bugguide states that they bite
all animals, including humans, mostly around around the head. These were "leg snipes":) Just this
week (7-19-2016) I was in Big Cottonwood Canyon taking pictures and the Snipe Flies were
unrelenting.  A word to the wise - wear long pants.  Carol Davis 7-25-2011

Symphoromyia snipe fly
"Mr. or Mrs. Snipe Fly sends his/her regrets that he/she will be unable to attend your
next camping party at or near Strawberry Reservoir due to an untimely death by a
vicious slap.  I am enclosing a photo of the deceased.". 
Carol Davis 7-25-2011
You may enjoy reading this article from the Oxford Journal about an encounter with snipe flies in Utah
in 1944.  I'm sure people besides me have alternative names for these biting flies that aren't fit to print. 
Added later:  I noticed in this article posted by the National Park Service that descriptive names for these
 beasts are common in the West. This is a really good article - it has everything you'll ever need to know
about snipe flies, including detailed drawings (you'll have to scroll down the page to find the article
since they have recently archived it along with some other information.)

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