The adult mosquito is a slender, long-legged insect with forward-pointing piercing and sucking mouthparts.
The adults are between 7 and 15 mm long with a wingspan much the same as the body length. The wings have well-developed venation and in some cases the wings have a fringed hind margin and the veins also have scales associated with them.
There is sexual dimorphism exhibited in the antennal structure. The male antennae are heavily covered in long hairs, whilst on the female, these hairs are largely absent.
All mosquitoes are dependent upon water for the survival of the immature stages of the life cycle.
The female mosquitoes lay their eggs on the water, sometimes singly and sometimes in what are known as “egg rafts” – a collection of eggs fixed together.
The larvae that emerge from the eggs are totally aquatic, feeding off biological material in the water. The larvae obtain their oxygen from the air via a breathing tube and therefore continually have to return to the surface of the water to breathe.
The pupae are formed from the final stage larvae and the pupa also obtains oxygen from the air through a breathing tube.
The adult emerges from the pupa and the adult females are invariably blood feeding while the males obtain their food from nectar, if at all.
The mosquitoes have worldwide distribution, mainly in warmer regions, with great potential as vectors of disease in many tropical and sub-tropical areas.
The mosquitoes that are encountered within most of Europe and North America do not transmit any serious diseases, despite the females being blood-feeders. What is significant though is that in some cases there can be a severe reaction to the blood meal having been taken. Secondary infection may result in quite significant wounds.
Treatment of adult flies consists of the use of residual insecticides and space sprays.
The presence of this insect indoors may indicate that attention to proofing is needed. Therefore flyscreening and the use of UV light traps is indicated.
Treatment of the larval development sites is not usually feasible. However, it may be possible to eliminate favourable sites such as water butts, cellar water etc.
Illustration: Culex pipens. culicine mosquito, house gnat.