Abstract

QUINTERO, Loriana  and  NAVARRO, Juan-Carlos. Intraspecific phylogeny and genetic variability of Culex quinquefasciatus Say (Diptera: Culicidae) with mitochondrial genes ND5 and COI. Bol Mal Salud Amb [online]. 2012, vol.52, n.1, pp.46-65. ISSN 1690-4648.

Culex quinquefasciatus Say (Diptera, Culicidae) is a mosquito belonging to the Pipiens complex with wide distribution in the world and in Venezuela, both urban and rural. Besides, it is a markedly anthropophilic vector of several viruses and parasites maintained in nature in a cycle enzootic bird-mosquito-bird. The wide distribution and occupation of larval habitats of anthropogenic origin may suggest the presence of geographical subpopulations, which may differentially participate in the transmission of pathogens. Phylogenetic analysis and haplotype networks with sequences of mitochondrial genes (cytochrome oxidase subunit I and subunit 5 of NADH dehydrogenase) of populations collected in nine locations (cemeteries) of Venezuela showed high interpopulation genetic homogeneity and a single phylogenetic entity (monophyly). It demostrated that the COI gene fragment had a higher resolution in the definition of the phylogeny of closely related species and genera level and correlated with the current classification. The ND5 gene variation is highly useful for population studies. However, this gene showed paraphyly between Cx. corniger and Cx. quinquefasciatus as an evidence of possible homogenization by inbreeding, introgression or infection with Wolbachia. The haplotype networks suggest expanding populations with high haplotype variability and genetic heterogeneity occurred within populations. Moreover, the analysis, showed homogeneity among populations with evolutionary implications in the dispersion of their populations and successful occupation in urban areas, as well as evidence of possible population bottleneck as consequence of insecticide control campaigns.

Keywords : Phylogeny; citochrome oxidase I; haplotypes network; mitochondrial DNA; urban mosquitoes; monophyly; ND5; paraphyly.