Culex tarsalis

Distinguished from other Culex species by the prominent black and white banding on the tarsi (legs). Can be separated from Culex quinquefasciatus (southern house mosquito) by leg banding pattern and geographic distribution. Molecular identification via cytochrome c oxidase subunit I (COI) gene sequencing confirms morphological identifications. In Florida, recently distinguished from Culex declarator by molecular methods.

Medium-sized mosquito with distinctive black and white banding on the legs. Typical Culex morphology with a blunt-tipped abdomen and resting posture with body parallel to the surface. Wing veins with scales arranged in characteristic pattern for the genus. Sexual dimorphism present: males have plumose antennae while females have sparsely haired antennae.

Breeds in standing freshwater including artificial containers, pools, and wetlands. In California urban environments, abundance increases following rainfall. Associated with agricultural areas where West Nile virus incidence is highest. Larval development occurs in aquatic habitats; adults found in terrestrial environments near breeding sites.

North America, with range extending from Canada through the United States into Mexico. Three genetically distinct population clusters identified in the western United States: Pacific, Sonoran, and Midwest. Documented in Florida as a new county record in Collier County (2021), though establishment status uncertain. Absent from extreme northern temperate zones.

Females blood-feed on vertebrate hosts; specific host species not documented in available sources. Males feed on nectar and other sugar sources. Autogenous populations can produce initial egg batch without blood meal.

Complete metamorphosis with egg, larval, pupal, and adult stages. Larval and pupal stages aquatic. Vitellogenin gene expression detected in larval and pupal stages but no protein production during this period. Autogenous strains can mature initial egg batch without blood feeding; subsequent gonotrophic cycles require blood meal.

Exhibits diapause as overwintering strategy. Host-seeking activity influenced by temperature and time of day, affecting efficacy of chemical control interventions. Oviposition behavior responds to semiochemicals associated with fish, which has been investigated for potential vector control applications. Autogeny documented in certain populations.

Key vector species for zoonotic arboviruses in western North America. Principal vector for West Nile virus in California agricultural areas. Transmits Saint Louis encephalitis virus, Western equine encephalitis virus, and avian malaria parasites (Plasmodium species affecting wild birds). Serves as host for viral superinfection exclusion interactions (Eilat virus vs. West Nile virus).

Major public health concern due to vector competence for multiple human pathogens. Target of surveillance and control programs in western United States. Subject of research on natural mosquito control through wetland ecosystem management. Genome sequenced to facilitate studies on insecticide resistance, diapause, and sex determination.

• Culex quinquefasciatusClosely related sister species with overlapping distribution in southern North America; distinguished by leg banding pattern, genetic divergence estimated at 15.8-22.2 million years, and smaller genome size (578 Mb vs. 790 Mb)
• Culex restuansSympatric in some areas; distinguished by oviposition behavior and morphological differences in larval and adult stages
• Culex declaratorRecently documented in same Florida county; distinguished by molecular identification and morphological characters

• vector
• mosquito
• arbovirus
• West Nile virus
• encephalitis
• medical entomology
• autogeny
• diapause

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
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• Whole-genome assembly of Culex tarsalis
• Whole genome assembly of Culex tarsalis
• Vitellogenin gene expression in autogenous Culex tarsalis
• Oviposition Behavior of Natural Populations of Culex tarsalis and Culex restuans (Diptera: Culicidae) in Artificial Pools
• Figure 1: USA distribution by state of Anopheles freeborni, Anopheles quadrimaculatus, and Culex tarsalis (Hayes et al., 2005; Venkatesan & Rasgon, 2010; Manguin, 2013).
• Aedes tortilis, Culex declarator, and Culex tarsalis: New County Records for Mosquito Species in Collier County, Florida
• Teasing apart the ovipositional responses of Culex tarsalisto semiochemicals associated with fish for use in vector control
• Virome profiling of Culex tarsalis through small RNA-seq: A challenge of suboptimal samples.
• Eilat virus (EILV) causes superinfection exclusion against West Nile virus (WNV) in a strain-specific manner in Culex tarsalis mosquitoes.
• A single-cell atlas of the Culex tarsalis midgut during West Nile virus infection.
• Co-Infection of Culex tarsalis Mosquitoes with Rift Valley Fever Phlebovirus Strains Results in Efficient Viral Reassortment.
• Temperature and time of host-seeking activity impact the efficacy of chemical control interventions targeting the West Nile virus vector, Culex tarsalis.