Craneflies - Tipulidae

Craneflies 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 the UK they are often referred to as 'daddy-long-legs'. They have several distinctive features and wing venation, so can be identified to family level from good photos fairly easily. 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, sometimes to species level, from good photographs. Be prepared to wait though, as there are not very many cranefly experts, they are busy and it is a specialist area. If you want to have a go at identifying your cranefly yourself, do try the extraordinary and marvellous Catalogue of the Craneflies of the World, a fully searchable database with many photos and illustrations.

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, but some species rest with wings folded over their bodies. Some species have the habit of bobbing up and down on their absurdly long legs. 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. When you see flocks of corvids in ploughed fields it is often leatherjackets that they are hunting.

Adult Tipulidae range in appearance from the subtle browns of Tipula spp to the striking black and oranges of Nephrotoma and Ctenophora spp. Several species are common and some engage in mating swarms.

Note that there are several closely related families and not all long legged flies are Tipulidae. The Limoniidae family is also well represented in France and look very similar.

Photographed by Loire Valley Nature:
Photos are numbered from left to right and top to bottom.

1-6 A female Tipula sp lays her eggs on plant material in a ditch in Preuilly-sur-Claise in March.

7 - 9 Spotted Craneflies Nephrotoma appendiculata, mating on our garden fence, April. The female is on the left.

10 - 11 female Nephrotoma crocata, a tiger cranefly, resting on box topiary in our front courtyard, April.

12 male Tipula vernalis, a common springtime species with a prominent dark line down the middle of its body, in the haymeadow in front of our orchard, April.

13 - 14 male Ctenophora festiva in the Foret de Preuilly.

15 female Nephrotoma quadrifaria.

16 female Tipula oleracea.

The rear end of a crane fly larva, as it disappears head first into the soil under a lawn.

The rear end of a crane fly larva, as it disappears head first into the soil under a lawn.
More info:
A post about Tipula maxima, the largest Tipulidae species in the region, on Aigronne Valley Wildlife.
A post on Days on the Claise with photos of Nephrotoma quadrifaria (including as prey of the Assassin Fly Empis tessellata).
A post showing mating Nephrotoma appendiculata on Days on the Claise.

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