Deer-Fly

Deer-fly (chrysops relictus)

The Twin-lobed Deer-fly is a species of horse-fly, and is generally considered to be one of the most beautiful of horse-flies. The yellow and black body, patterned wings, iridescent red and green eyes make it easily recognisable. Females have sharp biting mouthparts and feed on the blood of large mammals, usually cows and ponies, but humans are incidental targets too. The mouth parts of the males are different from the females, with the males feeding on nectar. Females are often found in shady or wooded areas using their sight (large compound eyes) to recognize passing prey. Deer-fly eggs are laid on stones and plants, in mud and close to water. Larvae hatch onto damp earth where they predate other invertebrates. These species of biting vector are capable of passing on many infections (includingTularaemia), and can be a real nuisance during the summer months and especially in hot, thundery weather. As one of the 30 species of horse-fly in the UK it is also one of the most frequently encountered in damp habitats.

Splayed Deer-fly (Chrysops caecutiens)

Square spot Deer-fly (Chrysops viduatus)

Deer-fly can be found throughout the United Kingdom.