Mosquitoes, of the family Culicidae, are slim, elegant, 5-6 mm long, grayish midge-like flies. There are also some peaceful midges, which are similar to the mosquito in appearance, for example the non-biting midges or chironomids, which are often seen in large swarms over lakes and bays. Mosquitoes are characterized by the long, thin, flexible proboscis on the front of the head, as well as by the fine scales that cover most of the body.
The mosquitoes have long sensory palps. Male mosquitoes have bushy palps, while female mosquitoes have shorter hair on their palps. Only female mosquitoes bite. In Denmark, there are 30 different biting species of mosquitoes, which may bite people when the opportunity presents itself.