True Flies

There are many families of flies that have aquatic larval and pupal stages, but are terrestrial as adults. Some of the more prominent of these flies are described briefly in the following paragraphs.

The mosquitoes (family Culicidae) are a diverse, well known, and important group of biting flies. Larval mosquitoes, also known as "wrigglers," are aquatic and feed on algae and organic debris, and the adult males feed on flower nectar. Female mosquitoes, however, require a blood meal from a bird or mammal before they can develop eggs. Many species of mosquitoes bite humans, and they can be an enormous cause of annoyance, as well as the means of spreading some important, even deadly, diseases. About 150 species of mosquitoes occur in North America, and in some habitats, for example, in northern forests during the summer, these blood-suckers can be enormously abundant and bothersome.

The black flies or buffalo gnats (family Simulidae) are small, dark-colored, hunch-backed flies. Female black flies require a blood meal to develop their eggs, and they obtain this food by biting the skin of a victim, and then sucking the blood that emerges from the wound. Black flies breed in cool streams, and they can be very abundant in some northern habitats. Unprotected animals have actually been killed as a result of the enormous numbers of bites that can be delivered during periods when black flies are abundant.

The horse flies and deer flies (family Tabanidae) are another group of fierce, biting flies with aquatic larvae and pupae, and terrestrial adults. Only the females require a blood meal—the males feed on nectar and plant juices. The eyes of deer flies are often extremely bright-colored, even iridescent.

The biting midges or no-see-ums (family Ceratopogonidae) are very small, blood-sucking flies with aquatic larval and pupal stages, but terrestrial adults. These diminutive pests can be quite abundant along the shores of lakes and oceans. These tiny flies can easily penetrate through fly screens and many types of clothing, and deliver bites that are much more painful than might be expected on the basis of the diminutive, lessthan one millimeter size of these insects.

The crane flies (family Tipulidae) have a superficial resemblance to gigantic mosquitoes with extremely long and delicate legs. The larvae of crane flies occur in aquatic or moist terrestrial habitats and mostly feed on decaying organic matter, while the adults are terrestrial and feed on nectar.

The phantom midges (family Chaoboridae) are mosquito-like insects, but they do not bite. Larval phantom midges are predators of other bottom-dwelling arthropods, and have almost transparent bodies—hence their common name.