Invertebrates
Notch-horned Cleg
Haematopota pluvialis · also called cleg, common cleg
On a hot, humid evening beside a damp meadow, a notch-horned cleg lands silently on a walker’s arm, her purple-banded eyes glittering.
Overview
The notch-horned cleg, Haematopota pluvialis, is a mottled-winged horsefly of damp meadows, woodland edges, and heaths across Europe and parts of Asia. Its silent bite and beautiful eyes make it one of the most familiar and least popular flies of the British summer.
A fly with beautiful eyes
Under a lens, the cleg’s eyes shimmer with bands of green and purple, a striking contrast with the unpleasant bite of the female.
Status
Not Evaluated, but widespread and common.
Notch-horned Cleg: common questions
Why is it called a cleg?
Cleg is an old name for the biting horseflies, and the notch-horned cleg is the commonest species of the group in Britain.
Why is the bite so sneaky?
The female lands quietly and slices the skin with blade-like jaws, so the bite is often noticed only when it starts to hurt.
Do males bite?
No, only the females take blood, to get protein for their eggs, while the males feed on nectar.
Where is the notch-horned cleg found?
It lives in damp meadows, woodland edges, and heaths across Europe and parts of Asia.