American Horse Fly

Subject: Unknown Fly
Location: Houston
May 11, 2016 9:22 am
Can you id this fly? About size of blow fly. Found outside warehouse, near septic tank.
Signature: Richard

American Horse Fly
American Horse Fly

Dear Richard,
We quickly identified your female Horse Fly on BugGuide as
Tabanus americanus, but we cannot fathom why it was not given the common name American Horse Fly based on its scientific species name.  According to BugGuide:  “Planet Earth’s largest tabanid.”  That would make it a pretty large Horse Fly.  Only female Horse Flies bite and feed on blood, and when there is no livestock available, they will bite humans.  The Encyclopedia of Life does refer to this as the American Horse Fly.

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