A Big Fly and Some Tiny Ants

The other day I photographed a magnificent horse fly on our barn wall. I'm a big fan of horse flies, so anyone who wants to carry on about how they bite can scroll on.

 

This one is a female Giant Dark Horse Fly Tabanus sudeticus (Fr. Taon des Sudètes). The species is supposedly the heaviest fly in Europe and females are about 25 mm in length. You can encounter adults on the wing throughout the summer, in dry pasture or woodland clearings. The larvae on the other hand are aquatic and eggs are laid on waterside plants.

Giant Dark Horse Fly females may bite you if you are wearing dark clothing, breathing heavily and warm and sweaty. But really they are more interested in getting their obligate blood meal from a cow or a horse. Without the nutrients they gain from biting a large mammal and sucking some blood they cannot lay viable eggs. If you are unlucky enough to be bitten, disinfect the wound immediately and take an antihistamine. You'll be fine unless you are unusually sensitive, in which case it may develop into a hard red lump about 10 cm across. Don't scratch the bite because it will get it infected.

I was so delighted to have a cooperative horse fly to photograph that I didn't even notice the ants until I was processing the photos. I didn't recognise them so I did what everyone does these days -- asked in the appropriate group on Facebook. A local entomologist got back to me to tell me they are Temnothorax sp.

Temnothorax ants are only 2 or 3 mm long, and live in small colonies of a couple of hundred individuals in dry dead wood or small cavities in rocks. There are at least 25 species in France and they occur throughout the country.