Crane fly
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 Adult
 Larva (leatherjacket)
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The crane flies (Tipulidae) are a family of insects resembling giant mosquitoes. Like the mosquito, they are in the order Diptera (flies). They are sometimes called mosquito eaters, mosquito hawks, or skeeter eaters. The Daddy long-legs is one of three unrelated arthropods, one of which is the crane fly. The other two are the harvestmen and vibrating, cellar or house spider. As such, Crane Flies are wrapped up in the myth of being the most poisonous spider, but unable to bite humans. This is incorrect: they are clearly insects rather than spiders, as they possess only six legs rather than the arachnid eight, and possess wings. Also, Crane flies do not bite humans. They drink only water when young and do not usually feed at all when they are adult, as they only live for a few days to mate.
In appearance they seem long and gangly, with very long legs, and a long slender abdomen. The wings are often held out when at rest, making the large halteres easily visible. Unlike mosquitoes, crane flies are weak and poor fliers, so they can be caught easily and without effort. However, it is very easy to accidentally break off their delicate legs when catching them, even without direct contact. This may help them to evade the birds who pursue them as prey.
Temperate species range up to 60 mm in size, while tropical species have been recorded at over 100 mm. They are attracted towards light. The females have swollen abdomen (because of eggs held inside) in comparison to the males. The female abdomen also ends in a pointed ovipositor that looks a bit like a stinger.
Adult crane flies feed on nectar or not at all, while their larvae, called leatherjackets, consume roots (such as those of turf grass in backyard lawns) and other vegetation, in some cases causing damage to plants. Therefore the crane fly is occasionally considered a mild turf pest in some areas. Some leatherjackets are aquatic.
At least 14,000 species have been described (most of them, 75%, by the specialist Charles P. Alexander), making Tipulidae the largest family of Diptera. The Giant Crane Fly (Holorusia rubiginosa) of the ' West' (Western United States) can reach 38 mm (1-3/8 inches). Some Tipula species are 64 mm (2-1/2 inches). There are many smaller species (known as bobbing gnats) that are mosquito-sized, but they can be distinguished by the V-shaped suture on the thorax and a lack of ocelli. They are the food source of many birds.
Morphology
Adults are very slender, long-legged flies; may vary in length from 2mm to 60 mm (tropical species > 100 mm) Adult mouthparts may occur on the end of a snout or short rostrum Larvae have a distinct head capsule, terminal abdominal segments often have long fleshy projections (almost like tentacles) Larvae are known for no more than 2% of the species.
Biology and Ecology
The life cycle is typically brief- egg, four larval stages, short pupal stage and short-lived adult Cycles among species vary from 6 weeks to 4 yrs (in Arctic species); in temperature regions typically 1-2 generationsa year. Crane flies occur from the Arctic to equatorial forests and even in some mountain ranges Most species are associated with moist temperate environments Immatures occur in amazingly diverse habitats These include:- fresh water, intertidal zones, cliff faces with film of wet algal growth, moist moss and lichen, decaying wood, mud, loamy soils by streams, leaf mining (a Hawaiian species), decaying plant materials, fungi, in organic matter in some bird and mammal nests, in crop fields, and in dry soils in lawns and pastures
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