Adults are large, light brown in color and appear to have wings without scales, which makes them easily distinguishable from other mosquitoes. The tip of the abdomen is blunt, with no inconspicuous patches or scales on the wings and the unscaled cross veins midway in the wing are nearly in line. The males of this species are noticeably smaller than the females and lack the bushy antennae of most other male mosquitoes. In addition, the males have long palpi on their heads, and “claspers” at the tip of their abdomen. This species is widely distributed through out the State.
This species occurs throughout most of North America from sea level to over 10,000 feet in altitude. Larvae are found in a wide variety of aquatic habitats from fresh water to salt marshes.
The eggs hatch into larvae (wigglers) which then feed on small organic particles and microorganisms suspended in the water. Feeding may take place at the bottom or near the water surface. Breathing takes place at the water surface and is accomplished by means of orienting upside down with the tip of their tail (siphon) pointing up. The larval stage can last from 5 to 14 days, depending upon the temperature. Under optimum conditions, development from egg to adult takes about 7 days. Molting takes place after the completion of the larval stage, giving rise to the pupa (tumbler). This is the resting stage and feeding does not take place as the larval form is being transformed into an adult. The pupa is active only if disturbed. When the transformation is completed (this usually takes 2 days), the new adult splits the pupal skin and emerges.
Larvae are found in a wide variety of standing water from freshwater to moderate levels of salinity, alkalinity or organic pollution. Sunlit sources are preferred egg laying sites, but larvae may also be found in shaded sources. This species is generally found in ground pools but may occur in artificial containers. Some typical sources for these larvae are ditches, canals, duck club ponds, rain ponds and irrigation and tail water impoundments.
The periods of peak abundance are fall, winter and spring. This species is strongly attracted to light. In light trap collections, they are the first caught in the spring and the last in fall.
HABITS (ADULT BEHAVIOR)
Females are active fliers and can disperse 5-10 miles from their emergence site.
ECONOMIC AND MEDICAL IMPORTANCE
It is important to remember that chemical control provides only temporary relief and should only be used until longer lasting measures can be implemented.
Insect repellents may be useful if it is necessary to be in an area where large numbers of these adults are present. Always read and follow the directions on the label carefully when using a repellent.