Genetic Differentiation of Populations within the Culex pipiens Complex and Phylogeny of Related Species

Abstract

The Culex pipiens complex consists of several species, subspecies, forms, races, physiological variants, or biotypes according to different authors and includes the 2 holarctic variants Cx. pipiens biotype pipiens and Cx. pipiens biotype molestus. Differences in morphological characters are overlapping and thus are delimited in their taxonomic value, even when behavioral and reproductive specializations are apparent. Our enzyme electrophoretic study included 7 geographic populations of Cx. pipiens biotype pipiens and 7 of the biotype molestus from several European countries. For comparison, 5 populations of Culex quinquefasciatus from Asia, Africa, and North America were examined. The aim was an assessment of the extent of genetic differences between local populations of the biotypes pipiens and molestus versus the degree of differentiation between geographic populations of both groups. Culex torrentium, Cx. modestus, Culex stigmatosoma, and Culex territans were studied for comparison as taxonomical well-defined species. The population genetic analyses revealed much higher genetic distances between local populations of Cx. pipiens biotype pipiens and Cx. pipiens biotype molestus compared to the low differentiation between geographic populations within each taxon. The UPGMA analysis and F-statistics position the geographic populations in discrete monophyletic clusters. Gene flow between local populations of the biotypes pipiens and molestus could be shown to be lower than gene flow between geographically distant populations within each of the 2 groups, leading to the conclusion that Cx. pipiens biotype molestus could be a distinct taxon. Culex quinquefasciatus could be diagnosed as genetically well separated, in particular by the diagnostic enzyme marker MDH (NADP). Two genetic enzyme markers were identified to differentiate Cx. torrentium from Cx. pipiens s.l. Culex modestus, Cx. stigmatosoma, and Cx. territans showed considerable genetic distances to the species of the Culex pipiens complex and between each other, and several genetic markers could be identified.

Population Structure and Distribution Patterns of the Sibling Mosquito Species Culex pipiens and Culex torrentium (Diptera: Culicidae) Reveal Different Evolutionary Paths

“…torrentium is essential but due to the difficulties in morphological identification, molecular methods are necessary to distinguish these forms. Today, commonly used techniques are the amplification of the cox1 gene fragment followed by restriction enzyme digestion of the amplicons [12], [70] or single-nucleotide polymorphism (SNP) analysis [71], as well as the second intron of the acetylcholinesterase- (ACE-2) or ITS-sequences of rDNA-based PCR assays and different allozyme markers [15], [72], [73]. Culex pipiens and Cx.…”

“…The larvae of Cx. pipiens can be found in nearly every natural, artificial, permanent or semi-permanent water body as well as in rural or urban areas [15], [16].…”

Genetic Structure ofCulex erraticusPopulations Across the Americas

“…aegypti and members of the Culex pipiens L. complex (Brown et al 2011, Edillo et al 2009, Weitzel et al 2009). This approach often involves comparisons carried out across large geographic areas to elucidate demographic and evolutionary history, including episodes of population expansion and divergence (Loaiza et al 2010).…”

Hamburger Klimabericht – Wissen über Klima, Klimawandel und Auswirkungen in Hamburg und Norddeutschland

“…modestus ein sensibler Indikator für einen Klimawandel. Da die Art bereits am Oberrhein nachgewiesen wurde (Weitzel et al 2009), könnte sie sich kontinuierlich in Deutschland ausgebreitet haben und ist vermutlich nicht über den Hafen importiert worden. Zu beachten ist, dass Cx.…”