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Culicidae (mosquitoes, gnats; order Diptera, suborder Nematocera) Family of very slender flies, which generally have an elongate, piercing proboscis, and stiff palps. The legs are long, the wings fringed with scales on the hind margins and along veins. The antennae of females are pilose, those of males plumose. Eggs are laid on or near the surface of water, singly or in compact masses as floating rafts. The transparant larva has a well-developed, mobile head, with dense tufts of bristles which are used to filter from the water the planktonic organisms and detritus on which the larva feeds, and with an anal respiratory siphon which it uses to renew its oxygen supply at the water surface after a period of submersion. The pupa is comma-shaped, very active, and able to swim beneath the water surface as a shadow passes across the surface. It breathes through a respiratory siphon held above the surface. Adult mosquitoes are well known as carriers of disease, especially those of the genera Aëdes, Culex and Anopheles. Males generally feed upon plant juices. Females have stronger, piercing mouth-parts and feed upon the blood of vertebrates, acting as intermediary hosts for malaria, yellow fever, filariasis, dengue, and several other disease organisms. Culex (pipiens) fatigans, distributed throughout the tropics, is the carrier of Wucheria bancrofti, the nematode responsible for elephantiasis in humans. Adults of this species have a characteristic resting attitude, with the body almost parallel with the substrate. Aëdes aegypti is the yellow-fever mosquito of the tropics and subtropics, a species that rarely breeds far from human habitations, laying its eggs in small water-containing receptacles such as tree holes, old tins, and bottles, or in broken coconut shells. Adult Anopheles (the malarial mosquito) can be distinguished by their resting attitude: the body makes an acute angle with the substrate as the body is held in line with the proboscis. A. maculipennis is the most important malarial vector in Europe. There are 3000 described species of Culicidae.