Culex Mosquitoes of California
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Culex  apicalis
Habitat/Ecology - Larvae are found in cut off pools along woodland water courses. Larvae present from April to December.  Overwinter as adults.
Hosts - Toads - lab colony. Reptiles and Passerine birds (detected by precipitin tests).
Distribution - Below 5,000 feet throughout California but not common on Central Valley floor.
Vector Potential / Diseases - Unknown. Believed to be zero due to feeding preferences.
Culex  bohart
Habitat/Ecology - Larvae are found along the edges of slow moving streams or isolated pools of streams in open to partly shaded areas.
Hosts - Toads - lab colony. Not known to bite humans.
Distribution - Widespread in the lowlands and foothills of California.
Vector Potential / Diseases - Unknown
Culex erythrothorax
Habitat/Ecology - Larvae usually found along the margins of tule swamps and ponds. Larvae found during fall, winter and spring (rarely in summer).
Hosts - Mammals - mostly rodents, rabbits, also birds and humans.
Distribution - Sylvan. Mainly foothill and coastal areas
Vector Potential / Diseases - West Nile Virus, WEE, SLE and Turlock viruses have been isolated from California populations. Is the primary vector of avian malaria in Kern County.
Culex  pipiens
Habitat/Ecology - Larvae prefer polluted or foul water high in organic content. Can occur in fresh water but not common.
Hosts - Primarily birds, some equine and rarely bovin and dog. Will bite hum>ans.
Distribution - Most widely distributed in the world. Throughout California
Vector Potential / Diseases - West Nile Virus, WEE and SLE viruses are present in California populations. At most a secondary vector in Kern Co. Lab studies show it to be an inefficient vector. SLE epidemics in Central States are attributed to this species.  VEE has been isolated and this species can serve as a vector of avian malaria.
Culex   reevesi
Habitat/Ecology - Larvae are found along the edges of ponds amoung heavy tule growths, algae and duckweed. Also along margins of heavily shaded swamp areas and isolated open crabholes
Hosts - Lab colonies fed on toads.
Distribution - Coastal Marin County and south
Vector Potential / Diseases - Unknown
Culex   restuans
Habitat/Ecology - Larvae found in relatively foul water in small depressions such as hoofprints
Hosts - Birds and mammals. Precipitin tests - 70% preferred Passeriform birds
Distribution - Very rare in Californian Primarily in Southern California. Also Sierra, Kern and Monterey Counties
Vector Potential / Diseases - Has been incriminated as a vector of Dog heartworm but may be confused with Culex territans. WEE has been isolated from a Canadian population. EEE was isolateted from a New Jersey population.
Culex  stigmatosoma
(formerly peus )
Habitat/Ecology - Larvae are found in both foul and slightly foul water from natural and artificial pools, catch basins, pastures, man-made containers, cess pools and secondary treatment sewage ponds. Overwinter in stumps and burrows
Hosts - Precipitin tests indicate mammals with some primarily feeding on birds. Does not normally bite humans
Distribution - Common throughout California except the high Sierra.
Vector Potential / Diseases - WEE, SLE and Turlock viruses have been isolated from California populations. Is th primary vector of avian malaria in Kern County
Culex tarsalis
Habitat/Ecology - Larvae in all freshwater sources except treeholes. Can tolerate coastal marsh water up to 1% salinity. Can occur in polluted water but not common. Adults rest by day in man made shelters, animal burrows and treeholes.
Hosts - Birds and mammals although in some localized populations a preference for avian hosts has been shown.
Distribution - Widespread up to 9,800 feet. Most abundant in hot valley areas with agricultural usage of water.
Vector Potential / Diseases - West Nile Virus, Primary vector of WEE and SLE. Has been associated with Turlock, Hart Park and Lokern viruses. Experiemental infections and trasmissions of JBE and VEE have been reported. Avian malaria vector.
Culex territans
Habitat/Ecology - Habitats similar to Culex apicalis but usually more open and at higher elevations
Hosts - Prefer cold blooded hosts - mostly bullfrogs and snakes
Distribution - Northern California at lower altitudes. Sierra only at 4,000-6,000 feet in Southern California
Vector Potential / Diseases - Vector of frog filaiasis in New Jersey.
Culex   thriambus
Habitat/Ecology - Larvae are found in rock pools, isolated ponds and hoofprints along streams and creeks
Hosts - Prefer passerine birds.
Distribution - Localized populations in foothill and coastal areas around the Central Valley. Rare
Vector Potential / Diseases - Unknown