This subfamily comprises a single genus, Toxorhynchites, which contains about 76 species which are mainly tropical, although a few species occur in North America, eastern Russia and Japan.
Adults are large (19 mm long, 24 mm wing spread) and colourful, being metallic bluish or greenish with black, white or red tufts of hair-like scales projecting from the posterior abdominal segments. Adults are easily recognized by the possession of a proboscis that is curved backwards in both sexes and is incapable of piercing the skin. Consequently since neither sex can bite, they are of no medical importance. Their larvae are also large (12-18 mm long), often dark reddish and, like those of the Culicinae, have a siphon.
They are predacious on larvae of other mosquitoes and on their own kind. They have occasionally been introduced into areas in the hope that their voracious larvae will help reduce the numbers of pest mosquitoes. Larvae are found mainly in container-habitats, such as tree-holes and bamboo stumps, tin cans and water-storage pots.