Crane flies are a group of very long legged flies in the sub-order of more primitive flies known as Nematocera - you could say they are really giant non-biting gnats. In Britain they are often referred to as 'daddy-long-legs', but this leads to confusion with several groups of spindly arachnids which are also widely known by this name. Crane flies have several distinctive features and wing venation, so can be identified to family level from good photos fairly easily.
Male Ctenophora festiva photographed in the Forest of Preuilly in May 2008, with my old compact digital Olympus camera. Check out those antennae!
They usually look quite ungainly in flight but they beat their wings very rapidly (50 - 70 times a second, much faster than dragonflies). At rest they mostly sit with their wings spread open. Be careful not to handle them, as the legs are fragile and snap off very easily. Females have pointed abdomens, with an ovipositor for laying eggs in the soil or decaying plant material. The larvae live on decaying material in soil or water. They dessicate easily, so in dry years do very poorly. The larvae are known as leatherjackets and some species are crop pests.
Male Ctenophora festiva, photographed in the Forest of Preuilly in May 2008.
Ctenophora festiva is an uncommon species that I see occasionally, and adults can be found in the forest here between April and July. Despite its striking appearance, which means that you are likely to notice it if it flies near you, it does not have an English or a French name. With its black and yellowy orange body it is mimicking a wasp. About 20 mm long, they have a black spot near the tip of the wing, the upper side of the thorax is black, and the hind legs have black bands. The feathery antennae of the males are extraordinary!
Their larvae develop in the trunks and stumps of rotting trees, particularly oaks and chestnuts, and as adults they don't stray far away from the stump they emerged from.
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