Volume 79, Issue 4
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


Members of the complex are considered as biting nuisance and vectors of important arbo-viruses including West Nile virus (WNV). To analyze the genetic structure of urban and rural populations of form pipiens and gain insights into behavioral implications, mosquitoes were collected from established WNV transmission foci in Connecticut from October 2006 through October 2007, examined by using microsatellite markers, and compared with other populations from neighboring states in the northeastern United States. The mean numbers of alleles per locus for the aboveground form pipiens populations ranged from 11.5 ± 2.3 to 13.2 ± 2.4 and were not significantly different. In contrast, form molestus had greatly reduced allelic diversities with an average of 4.4 ± 1.2 alleles per locus, which was significantly lower than that of any of the form pipiens populations analyzed. We did not detect significant genetic differences between urban and rural populations of form pipiens from Connecticut nor did we observe temporal genetic changes. However, in a comparative analysis with populations of neighboring states, New Jersey, New York, and Massachusetts, genetic variations associated with geographic distance were identified. In the analyses of Bayesian clustering and principal component analysis, we identified two clusters separating form molestus from form pipiens populations, indicating that form molestus was genetically distinct from any of the form pipiens populations examined during this study.


Article metrics loading...

The graphs shown below represent data from March 2017
Loading full text...

Full text loading...



  1. Andreadis TG, Anderson JF, Vossbrinck CR, 2001. Mosquito surveillance for West Nile virus in Connecticut, 2000: isolation from Culex pipiens, Cx. restuans, Cx. salinarius, and Culiseta melanura. Emerg Infect Dis 7 : 670–674. [Google Scholar]
  2. Andreadis TG, Anderson JF, Vossbrinck CR, Main AJ, 2004. Epidemiology of West Nile virus in Connecticut: a five-year analysis of mosquito data 1999–2003. Vector Borne Zoonotic Dis 4 : 360–378. [Google Scholar]
  3. Bernard KA, Maffei JG, Jones SA, Kauffman EB, Ebel G, Dupuis AP 2nd, Ngo KA, Nicholas DC, Young DM, Shi PY, Kulasekera VL, Eidson M, White DJ, Stone WB, Kramer LD, 2001. West Nile virus infection in birds and mosquitoes, New York State, 2000. Emerg Infect Dis 7 : 679–685. [Google Scholar]
  4. Lukacik G, Anand M, Shusas EJ, Howard JJ, Oliver J, Chen H, Backenson PB, Kauffman EB, Bernard KA, Kramer LD, White DJ, 2006. West Nile virus surveillance in mosquitoes in New York State, 2000–2004. J Am Mosq Control Assoc 22 : 264–271. [Google Scholar]
  5. Vinogradova EB, 2000. Culex pipiens pipiens Mosquitoes: Taxonomy, Distribution, Ecology, Physiology, Genetics, Applied Importance and Control. Sofia, Bulgaria: Pensoft Publishers.
  6. Apperson CS, Harrison BA, Unnasch TR, Hassan HK, Irby WS, Savage HM, Aspen SE, Watson DW, Rueda LM, Engber BR, Nasci RS, 2002. Host-feeding habits of Culex and other mosquitoes (Diptera: Culicidae) in the Borough of Queens in New York City, with characters and techniques for identification of Culex mosquitoes. J Med Entomol 39 : 777–785. [Google Scholar]
  7. Apperson CS, Hassan HK, Harrison BA, Savage HM, Aspen SE, Farajollahi A, Crans W, Daniels TJ, Falco RC, Benedict M, Anderson M, McMillen L, Unnasch TR, 2004. Host feeding patterns of established and potential mosquito vectors of West Nile virus in the eastern United States. Vector Borne Zoonotic Dis 4 : 71–82. [Google Scholar]
  8. Molaei G, Andreadis TG, Armstrong PM, Anderson JF, Vossbrinck CR, 2006. Host feeding patterns of Culex mosquitoes and West Nile virus transmission, northeastern United States. Emerg Infect Dis 12 : 468–474. [Google Scholar]
  9. Harbach RE, Harrison BA, Gad AM, 1984. Culex (Culex) molestus Forskal (Diptera: Culicidae): neotype designation, description, variation, and taxonomic status. Proc Entomol Soc Wash 86 : 521–542. [Google Scholar]
  10. Spielman A, 1964. Studies on autogeny in Culex pipiens populations in nature. I. Reproductive isolation between autogenous and anautogenous populations. Am J Hyg 80 : 175–183. [Google Scholar]
  11. Spielman A, 2001. Structure and seasonality of nearctic Culex pipiens populations. Ann NY Acad Sci 951 : 220–234. [Google Scholar]
  12. Spielman A, 1971. Studies on autogeny in natural populations of Culex pipiens. II. Seasonal abundance of autogenous and anautogenous populations. J Med Entomol 8 : 555–561. [Google Scholar]
  13. Fonseca DM, Keyghobadi N, Malcolm CA, Mehmet C, Schaffner F, Mogi M, Fleischer RC, Wilkerson RC, 2004. Emerging vectors in the Culex pipiens complex. Science 303 : 1535–1538. [Google Scholar]
  14. Selkoe KA, Toonen RJ, 2006. Microsatellites for ecologists: a practical guide to using and evaluating microsatellite markers. Ecol Lett 9 : 615–629. [Google Scholar]
  15. Reiter P, 1983. A portable, battery-powered trap for collecting gravid Culex mosquitoes. Mosq News 43 : 496–498. [Google Scholar]
  16. Kent RJ, Harrington LC, Norris DE, 2007. Genetic differences between Culex pipiens f. molestus and Culex pipiens pipiens (Diptera: Culicidae) in New York. J Med Entomol 44 : 50–59. [Google Scholar]
  17. Darsie RFJ, Ward RA, 1981. Identification and geographical distribution of the mosquitoes of North America, north of Mexico. Mosq Syst 1 (Suppl): 1–313. [Google Scholar]
  18. Andreadis TG, Thomas MC, Shepard JJ, 2005. Identification guide to the mosquitoes of Connecticut. Conn Agric Exp Stn Bull 966 : 1–178. [Google Scholar]
  19. Crabtree MB, Savage HM, Miller BR, 1995. Development of a species-diagnostic polymerase chain reaction assay for the identification of Culex vectors of St. Louis encephalitis virus based on interspecies sequence variation in ribosomal DNA spacers. Am J Trop Med Hyg 53 : 105–109. [Google Scholar]
  20. Van Oosterhout C, Hutchinson WF, Wills DP, Shipley P, 2004. Program note: micro-checker: software for identifying and correcting genotyping errors in microsatellite data. Mol Ecol Notes 4 : 535–538. [Google Scholar]
  21. Rousset F, 2007. Genepop’007: a complete reimplementation of the Genepop software for Windows and Linux. Mol Ecol Res 8 : 103–106. [Google Scholar]
  22. Guo SW, Thompson EA, 1992. Performing the exact test of Hardy-Weinberg proportion for multiple alleles. Biometrics 48 : 361–372. [Google Scholar]
  23. Raymond M, Rousset F, 1995. GENEPOP (version 1.2): population genetics software for exact tests and ecumenicism. J Hered 86 : 248–249. [Google Scholar]
  24. Rice WR, 1989. Analyzing tables of statistical tests. Evolution Int J Org Evolution 43 : 223–225. [Google Scholar]
  25. Weir BS, Cockerham CC, 1984. Estimating F-statistics for the analysis of population structure. Evolution Int J Org Evolution 38 : 1358–1370. [Google Scholar]
  26. Slatkin M, 1995. A measure of population subdivision based on microsatellite allele frequencies. Genetics 139 : 457–462. [Google Scholar]
  27. Excoffier L, Laval G, Schneider S, 2005. Arlequin version 3.0: an integrated software package for population genetics data analysis. Evol Bioinform Online 1 : 47–50. [Google Scholar]
  28. Goodman SJ, 1997. R ST Calc: a collection of computer programs for calculating unbiased estimates of genetic differentiation and determining their significance for microsatellite data. Mol Ecol 6 : 881–885. [Google Scholar]
  29. Rousset F, 1997. Genetic differentiation and estimation of gene flow from F-statistics under isolation by distance. Genetics 145 : 1219–1228. [Google Scholar]
  30. Mantel N, 1967. The detection of disease clustering and a generalized regression approach. Cancer Res 27 : 209–220. [Google Scholar]
  31. Goudet J, 2001. FSTAT, a program to estimate and test gene diversities and fixation indices (version 2.9.3). Available at: http://wwwunilch/izea/softwares/fstathtml. Updated from Goudet (1995).
  32. Pritchard JK, Stephens M, Donnelly P, 2000. Inference of population structure using multilocus genotype data. Genetics 155 : 945–959. [Google Scholar]
  33. Rosenberg NA, 2004. Distruct: a program for the graphical display of population structure. Mol Ecol Notes 4 : 137–138. [Google Scholar]
  34. Bahnck CM, Fonseca DM, 2006. Rapid assay to identify the two genetic forms of Culex (Culex) pipiens L. (Diptera: Culicidae) and hybrid populations. Am J Trop Med Hyg 75 : 251–255. [Google Scholar]
  35. Smith JL, Keyghobadi N, Matrone MA, Escher RL, Fonseca DM, 2005. Cross-species comparison of microsatellite loci in the Culex pipiens complex and beyond. Mol Ecol Notes 5 : 697–700. [Google Scholar]
  36. Keyghobadi N, Matrone MA, Ebel GD, Kramer LD, Fonseca DM, 2004. Microsatellite loci from the northern house mosquito (Culex pipiens), a principal vector of West Nile virus in North America. Mol Ecol Notes 4 : 20–22. [Google Scholar]
  37. Wattier R, Engel CR, Saumitou-Laprade P, Valero M, 1998. Short allele dominance as a source of heterozygote deficiency at microsatellite loci: experimental evidence at the dinucleotide locus Gv1CT in Gracilaria gracilis (Rhodophyta). Mol Ecol 7 : 1569–1573. [Google Scholar]
  38. Gingrich JB, Williams GM, 2005. Host-feeding patterns of suspected West Nile virus mosquito vectors in Delaware, 2001–2002. J Am Mosq Control Assoc 21 : 194–200. [Google Scholar]
  39. Kilpatrick AM, Kramer LD, Jones MJ, Marra PP, Daszak P, 2006. West Nile virus epidemics in North America are driven by shifts in mosquito feeding behavior. PLoS Biol 4 : e82. [Google Scholar]
  40. Savage HM, Aggarwal D, Apperson CS, Katholi CR, Gordon E, Hassan HK, Anderson M, Charnetzky D, McMillen L, Unnasch EA, Unnasch TR, 2007. Host choice and West Nile virus infection rates in blood-fed mosquitoes, including members of the Culex pipiens complex, from Memphis and Shelby County, Tennessee, 2002–2003. Vector Borne Zoonotic Dis 7 : 365–386. [Google Scholar]
  41. Hamer GL, Kitron UD, Brawn JD, Loss SR, Ruiz MO, Goldberg TL, Walker ED, 2008. Culex pipiens (Diptera: Culicidae): a bridge vector of West Nile virus to humans. J Med Entomol 45 : 125–128. [Google Scholar]
  42. Kilpatrick AM, Kramer LD, Jones MJ, Marra PP, Daszak P, Fonseca DM, 2007. Genetic influences on mosquito feeding behavior and the emergence of zoonotic pathogens. Am J Trop Med Hyg 77 : 667–671. [Google Scholar]
  43. Byrne K, Nichols RA, 1999. Culex pipiens in London underground tunnels: differentiation between surface and subterranean populations. Heredity 82 : 7–15. [Google Scholar]

Data & Media loading...

Supplemental figure

Supplemental tables A1-A6

  • Received : 26 Feb 2008
  • Accepted : 15 Jul 2008

Most Cited This Month

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error