Male Black Horse Fly

Subject: Big cool fly
Location: Exeter, NH
August 19, 2016 5:45 am
I saw this on my car this morning. I wanted to know what it was. Thank you.
Signature: Cheryl

Male Black Horse Fly
Male Black Horse Fly

Hi Cheryl,
This is a male Black Horse Fly,
Tabanus atratus.  According to BugGuide:  “Very wide range of habitats; generally near aquatic environments (Long 2001). Requires moist environments in which to lay eggs, and mammals to feed on (Long 2001). Larvae live ‘along the margins of ponds and ditches.'”  BugGuide also notes:  “Females feed on mammalian blood; males, which lack mandibles, feed on nectar and plant juices (Long 2001). Especially prone to attack cattle and other livestock.”  When livestock are not available, female Horse Flies will bite humans.  You can tell your individual is a male because of the large, close-set eyes.  Female Horse Flies have a space between their eyes.

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