23 Mosquito Species of Contra Costa County

Genus, species	Common Name	Larval habitat	Biting Behavior	Time of day	Peak Season	Flight range	Medical Importance
Anopheles franciscanus	none	shallow sunlit pools with algae	large mammals	dusk and dawn	summer	< 1 mile	occasional pest
Anopheles freeborni	Western malaria mosquito	rice fields; clear sunlit seepages with algae	large mammals, humans	dusk and dawn	summer	10 miles	malaria vector
Anopheles occidentalis	none	ponds, creeks, seepages	large mammals	dusk and dawn	summer	unknown	no known significance
Anopheles punctipennis	Woodland malaria mosquito	cool shaded grassy pools, streams, creeks	large mammals, humans	dusk and dawn	summer	> 1 mile	malaria vector
Aedes dorsalis	none	Coastal salt marshes, inland alkaline areas	large mammals, humans	day and night	summer, fall	< 10 miles	Secondary CE & WEE vector, localized pest
Aedes melanimon	none	Duck club ponds, irrigated pastures and fields	large mammals, humans	dusk and day	summer, fall	> 10 miles	Primary CE vector, secondary WEE vector, possible WNV vector, major pest
Aedes nigromaculis	Irrigated pasture mosquito	Irrigated pastures and alfalfa fields	large mammals, humans	dusk and day	summer	< 20 miles	Localized pest
Aedes sierrensis	Western tree hole mosquito	Tree holes, tires and other man-made containers	small mammals, humans	dusk and day	spring	< 1 mile	Dog heartworm vector, localized pest
Aedes squamiger	California salt marsh mosquito	Coastal salt marshes	humans	dusk and day	winter	10-20 miles	Localized pest, possible CE vector
Aedes washinoi	none	Rainwater pools	large mammals, humans	dusk and day	spring	< 1 mile	Localized pest, possible CE vector
Aedes vexans	Inland floodwater mosquito	Irrigated pastures, riparian pools	large mammals, humans	day and dusk	summer, fall	> 10 miles	Localized pest, secondary dog heartworm vector, possible WNV vector
Culex erythrothorax	Tule mosquito	Ponds, lakes, marshes with tules and cattails	birds, humans	dusk and day (shaded areas)	spring, summer, fall	< 1 mile	Localized pest, secondary WNV vector
Culex apicalis	none	Creeks, woodland pools	birds, reptiles	unknown	rare	unknown	no known significance
Culex boharti	none	Creeks and streams	frogs, toads	unknown	rare	unknown	no known significance
Culex pipiens	Northern house mosquito	Polluted water (sewer plants, abandoned pools, catch basins etc)	birds, humans	night	spring, summer, fall	< 1 mile	Primary WNV vector, secondary SLE vector, localized nuisance
Culex stigmatosoma	Banded foul water mosquito	Polluted water (sewer plants, dairy sumps etc)	birds	night	rare	< 10 miles	Secondary WNV and SLE vector
Culex tarsalis	Western encephalitis mosquito	Widespread in clear water (agricultural areas, untended swimming pools, creeks etc)	birds, mammals, humans	night	summer, fall	3-15 miles	Primary WNV, WEE and SLE vector
Culex territans	none	Creeks, woodland pools	reptiles, amphibians	dawn and dusk	rare	unknown	no known significance
Culex thriambus	none	Rock pools, ponds, hoof prints	birds	unknown	rare	unknown	no known significance
Culiseta incidens	Cool weather mosquito	Widespread in natural or manmade sources	large mammals, humans	night	spring, summer, fall	< 5 miles	Localized pest, possible secondary WNV vector
Culiseta inornata	Large winter mosquito	Widespread in natural or manmade sources, marshes	large mammals, humans	night	winter	< 5 miles	Localized pest, possible secondary WNV vector
Culiseta particeps	none	Creeks, streams, marshes	unknown (probably large mammals)	night	spring	unknown	no known significance
Orthopodomyia signifera	none	Tree holes	birds	unknown	rare	unknown	no known significance

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