Anopheles is the Greek word for troublesome.
Anopheline mosquitoes are different in many respects from other genera. Because of these differences they were placed in a separate tribe Anophelini (Carpenter & La Casse 1955) and more recently in a separate subfamily Anophelinae (Knight & Stone 1977).
All stages of anophelines are distinct from other mosquitoes in British Columbia and there should be no difficulty in identifying them in the field. Adults have narrow wings and look very long and slender. They often adopt a well-known resting attitude, where the mosquito almost stands on its head with the proboscis, thorax and abdomen in a straight line. They indubitably adopted this position long before the evolution of man, but one is tempted to think of it as cryptic adaptation when they sit on rough-cut wooden surfaces looking deceptively like splinters.
The palps of both males and females are about as long as the proboscis; those of the male look bushy because of the long apical setae. All our species have the dark scales on some of the wing veins aggregated into spots or patches. In both sexes, the posterior margin of the scutellum is evenly rounded with a fringe of regularly distributed setae and the abdomen bears setae but no scales.
The females hibernate and can be found in winter resting under culverts, bridges and eaves and inside sheds where they usually settle in the roof. Far from civilization they hibernate in burrows, caves, hollow trees and other sheltered places.
The eggs are laid singly among vegetation at the margin of bodies of fresh water-from lakes to small ditches with slowly-flowing water. The eggs have buoyant lateral "wings," not found in our other mosquitoes, and they float horizontally.
The larvae are slim, their head and thorax relatively narrower than in the other genera. Special fan-shaped (palmate) setae on the dorsal surface of the abdomen enable them to float horizontally. In this position the eighth segment can break through the surface film. They feed here on particles from the film or "graze" on larger particles below the surface and on the bottom. Anopheline larvae have an extremely short respiratory siphon. The pecten, unlike that of our other mosquitoes does not have separate teeth, but is part of a sclerotised plate on segment VIII. Because there are few differences between the larvae of the three anophelines found in the Province, only An. earlei is illustrated.
Larvae from the related families Chaoboridae and Dixidae can be misidentified as anophelines. Chaoborid larvae, however, have prehensile antennae and are all predaceous. Of the species that could be confused with mosquito larvae, the commonest in this area is Eucorethra underwoodi which has no siphon and floats horizontally on the surface. It has a squarish head and stout bristly looking thorax and should not be difficult to identify when once seen with the slimmer anophelines. If any chaoborid larvae are reared or collected they should be separated from the mosquitoes or there may be a sharp decline in the population of the latter. Although the dixids are dark and slim like anophelines, they have the unusual habit of attaching themselves to the sides of a container in the shape of a U.
Anopheline pupae are not markedly different from those of other genera. A key that separates pupae to their genera is found in Bohart and Washino (1978).
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