Mosquitoes of North America - Species Profile: Aedes canadensis

     Aedes canadensis (Theobald 1901), subgenus Ochlerotatus.

Aedes candensis ssp. canadensis
Photo by author in Nacogdoches County, Texas

        This seasonally common species is found throughout the eastern and central United States and Canada, spreading northwest from the dustbowl region into Canada and Alaska. A woodland inhabitant, Aedes canadensis reaches peak activity in mid-summer evenings. Eggs are laid in wet depressions in forest soil that fill with water in fall and winter and remain until spring. 

        Superficially similar to the abundant Aedes vexans, this species can be differentiated from the latter by the white bands on the tarsi (legs): in Ae. vexans the bands are basal only, located at the beginning of each tarsal segment, and very narrow; Ae. canadensis has usually broad white tarsal bands that cross the tarsal joints (making the bands basal and apical - i.e. located at the beginning and end of each tarsal segment). Ae. vexans also differs from Ae. canadensis by the presence of a double-lobed pattern on the abdominal terga (top portion of abdominal segments), which the latter species lacks. 

Other Aedes mosquitoes with basal and apical tarsal banding include the Aedes dorsalis group (Ae. dorsalis, melanimon, and campestris), which have broad, contrasting scales on the wings, subgenus Georgecraigius mosquitoes (Ae. atropalpus, epactius, and fluviatilis) and Jarnellius (Ae. sierrensis and monticola), which are tan and black patterned on the scutum and have a pale patch of scales at the base of wing vein C, and Aedes togoi (restricted to WA, BC), which has a distinct lyre-shaped pattern on the scutum.

        There are two subspecies of Aedes canadensis, A. c. canadensis which is the dominant subspecies and exhibits broad tarsal banding, and A. c. mathesoni, sometimes classified as a separate species, which has narrow tarsal banding and is only found in the Southeast on the coast and in the coastal plain of Alabama, Georgia, Florida, and South Carolina.

Aedes candensis ssp. canadensis
Photo by @apistopanchax on iNaturalist

Aedes candensis ssp. mathesoni
Photo by @richardthecrittercatcher on iNaturalist

Sources

Burkett-Cadena, N. D. (2013). Mosquitoes of the Southeastern United States. Tuscaloosa, AL: The University of Alabama Press.

Darsie, R. F., and Ward, W. A. (1981). Identification and Geographical Distribution of the Mosquitoes of North America, North of Mexico. Fresno, CA: American Mosquito Control Association.