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True Flies, Mosquitoes, Gnats and Midges (Diptera)

General Information about True Flies, Mosquitoes, Gnats & Midges (Diptera)
Life history True flies can spend from a few weeks to 2 years as larvae in the water.
Diversity There are about 29 different families of true flies that have larvae that are aquatic in North America.
Long, soft and fleshy bodies. Some kinds have hardened skin on their heads. There are no wing pads or segmented legs and larvae do not use a case. Some larvae move around using their prolegs (unjointed legs).
Habitat & Feeding True fly larvae live in a wide range of habitats: pitcher plants, tree holes, wet soils mud puddles, seeps, springs, wetlands, streams, ponds, lakes, and rivers. Larval feeding is diverse; different kinds of larvae use almost every type of feeding strategy: shredders (eat decaying plant material), scrapers (eat algae off rocks), collector-gatherers (eat fine organic material), collector-filterers (eat fine organic material collected from the flowing water), or predators.
Water quality indicator status This group can provide useful information to biomonitoring studies because several of the families have larvae that are very tolerant of pollution and environmental stress, while some families are also very sensitive to pollution.
Fun facts
  • One kind of larvae live in rainwater or dew trapped in plants. Another kind of larvae can live in a natural crude oil seep.
  • The blood of some larvae in the non-biting midge family (Chironomidae) has hemoglobin to transport oxygen; this allows them to live in very low oxygen environments. Also, their bodies look red
image of Athericicdae
Family: Athericicdae
image of Simuliidae
Family: Simuliidae

image of Tabanidae
Family: Tabanidae
image of Chironomus
Family: Chironomus

image of Hexatoma
Hexatoma sp.
Image of true fly in the Chironomidae family.
Family: Chironomidae