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Anopheles Mosquitoes of California


Anopheles franciscanus
Habitat/Ecology - Larvae in slow moving streams and pools of water containing rich growth of green algae, exposed to good sun. Also in rice fields. Over winter as adults. Rarely found in human habitations.
Hosts - Primarily mammalian rabbits, cattle, horses, domestic pets, rodents and chickens. Precipitin tests showed fed on reptiles (from a Sacramento population).
Distribution - Widespread - recorded from all counties except El Dorado, Modoc, Mono, Sierra and San Francisco. From -200' to 5,200'
Vector Potential / Diseases - Main Drain Virus has been isolated from a San Diego population. Avian malaria was detected in Kern Co. population. Has been infected with Plasmodium vivax under laboratory conditions.
 Anopheles freeborni
Habitat/Ecology - Larvae prefer clear, fresh seepage water in sunlit or partly shaded pools; roadside ditches with grass; rice fields over winter as adults.
Hosts - Primarily mammalian with rabbits a favored host. Also cattle, horses and dogs. Will aggressively bite humans when encountered.
Distribution - Greatest success in the Sacramento Valley. Death Valley to Sierra Co. to 6,000 feet.
Vector Potential / Diseases - Most important vector of Plasmodium vivax. Has shortest sporogenous cycle (8 days) of an California species of Anopheles. Under Lab conditions was a successful vector of avian malaria and VEE. Is a vector of Myxoma virus of rabbits. SLE has been isolated from a Sacramento population.
 Anopheles hermsi
Habitat/Ecology -  Similar to Anopheles freeborni
Hosts -
Distribution - Were known as the Southern form of Anopheles occidentalis. Found in Southern California. From San Louis Obispo Co. South and San Mateo Co.
Vector Potential / Diseases - Primary vector of malaria in San Diego County
 Anopheles occidentalis
Habitat/Ecology -  Larvae found in ponds, creeks, streams, swamps and seepages. Peak abundance of larvae and adults in May and July. Over winter as adults and larvae.
Hosts - Rarely bites humans. Precipitin tests indicate a preference for bovine blood (70%) and then horse (28%).
Distribution - Coastal California
Vector Potential / Diseases - Under experimental conditions has successfully transmitted Plasmodium vivax.
 Anopheles punctipennis
Habitat/Ecology -  Larvae mostly found in clear, shaded pools along creeks and streams in foothill areas. Occasionally found in foul water. Do not tolerate saline water.
Hosts - Feed on large mammals with cows as the preferred host (Precipitin tests). Also feed on horse, sheep, birds, cats and humans.
Distribution - Localized populations along the coastal and interior foothill areas of the state to the Tehachapi Mountains.
Vector Potential / Diseases - Successfully infected with Plasmodium vivax and Plasmodium falciparum under lab conditions. Has successfully transmitted Plasmodium vivax. Has been reported as a vector of Dog heartworm.