Horse Fly: Male and Female Eye Comparison

Male and Female Horse Flies Feeding on Parsley
Location: Clarksburg, MA
August 18, 2011 10:04 am
Hello, saw your recent horse fly post and thought this might be a nice follow-up. I’m not sure of the species, but the images show a male and a female horse fly feeding on the flowers of parsley. The side view image is of a female. I can say both males and females have been coming around to my parsley the past few years, and pretty much have ignored me and my dog with the exception of one female, who I must have annoyed, after a particularly long photo session, because at the very end she bit my hand. (Picture of my resulting Stay Puft Marshmallow hand not included.)
Signature: Michael Marlow

Horse Fly

Hi Michael,
Thank you so much for sending these awesome images for a wonderfully informative posting.  Most of the Horse Fly images we receive are the genus
Tabanus, however, your flies appear to be Hybomitra cincta, which we identified on BugGuide.  Of the genus, BugGuide indicates:  “The 55 species are mostly northern, Canada and Alaska; being replaced in the remaining USA by Tabanus.”

Eyes of female Horse Fly

Your close up photos beautifully illustrate how the eyes of the female, the blood sucker, have a space between them, while the eyes of the male, who feeds exclusively on nectar, have no spacing between them.

Eyes of a Male Horse Fly

3 thoughts on “Horse Fly: Male and Female Eye Comparison”

  1. i found one in my room and it is a male happy i put it in a clear cup with a lid and finding out some very cool things about it


Leave a Comment