Snipeflies - Rhagionidae

To identify flies to family level use a simple wing venation key such as A Key to the Families of British Diptera, an AIDGAP by D. Unwin, published by the FSC and available as a free download (scroll down to the titles list) or a more detailed key which includes many physical characters such as The European Families of the Diptera by P. Oosterbroek. The expert dipterists on the DipteraInfo forum are also very happy to identify, often to species level, from good photographs.

Snipeflies are very much associated with marshes, damp woods, tree lined riverbanks and similar wet habitats. A few species can be locally abundant and it is not uncommon to have them land on your clothing. Don't be alarmed, as they do not bite. They are also often referred to as downlooker flies, because of their habit of resting head down on tree trunks. This behaviour is actually more or less limited to the well camouflaged species of Rhagio with mottled wings. Other snipeflies are more likely to sit on leaves.

The most common species is the Downlooker Snipefly R. scolopaceus, a fairly conspicuous species which is widespread because it is not too fussy about habitats. You are also likely to encounter Chrysopilus spp, and there are a few other, rarer, genera. As a rule, snipefly abundance can be badly affected by drought, although they seemingly cope fairly well with modern drainage schemes and the trend for change from broadleaf to coniferous forests.

They are quite distinctive flies, with conical abdomens and a characteristic way of posing. Don't confuse them with the unrelated Scorpion Fly Mecoptera

Rhagio vitripennis:
This species is one of only a few with dark shadowed wing markings, although not as strongly as R. scolopaceus. R. vitripennis is found in damp grassland and on the edges of damp woodland in the summer. The female pictured below landed on someone's shirt as we surveyed damp improved pasture in the Brenne, May.

Marsh Snipefly R. tringarius:
A clear winged species, more restricted to open marshes. It has no dark markings on the wings at all, not even the stigma, and is usually found sitting on vegetation in damp grassland. They like lots of lush grass and vegetation in damp meadows or marshes. The body colour can vary greatly. Common in lowland areas such as here, flying from May to September. The male below was photographed in the Brenne, near the Maison de Nature hide.

References and Further Reading:
Mark van Veen's excellent and fairly easy to use key to the Rhagio of Northwest Europe is here if you want to try identifying your own (not too much technical jargon).

British Soldierflies and their allies by Alan Stubbs and Martin Drake, a landmark publication covering not just Snipeflies but Soldierflies, Beeflies, Horseflies and Robberflies in thorough detail from identification keys to ecology.

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