Population Genetic Structure of Aedes fluviatilis (Diptera: Culicidae)

Abstract

Although Aedes fluviatilis is an anthropophilic mosquito found abundantly in urban environments, its biology, epidemiological potential and genetic characteristics are poorly understood. Climate change and urbanization processes that result in environmental modifications benefit certain anthropophilic mosquito species such as Ae. fluviatilis, greatly increasing their abundance in urban areas. To gain a better understanding of whether urbanization processes modulate the genetic structure of this species in the city of São Paulo, we used eight microsatellite loci to genetically characterize Ae. fluviatilis populations collected in nine urban parks in the city of São Paulo. Our results show that there is high gene flow among the populations of this species, heterozygosity deficiency and low genetic structure and that the species may have undergone a recent population expansion. There are two main hypotheses to explain these findings: (i) Ae. fluviatilis populations have undergone a population expansion as a result of urbanization; and (ii) as urbanization of the city of São Paulo occurred recently and was quite intense, the structuring of these populations cannot be observed yet, apart from in the populations of Ibirapuera and Piqueri parks, where the first signs of structuring have appeared. We believe that the expansion found in Ae. fluviatilis populations is probably correlated with the unplanned urbanization of the city of São Paulo, which transformed green areas into urbanized areas, as well as the increasing population density in the city.

Wing variation in Culex nigripalpus (Diptera: Culicidae) in urban parks

“…quinquefasciatus and Cx. nigripalpus , which are widely found throughout the urban environment [ 17 , 31 , 36 , 48 , 49 ].…”

“…Genotypic markers are frequently used to investigate the microevolution of mosquitoes [ 27 – 31 ]. However, wing geometric morphometrics are not only useful for assessing microevolution events but can also provide valuable information on phenotypic variability and population structure [ 32 – 34 ].…”

New record and extended geographical distribution of Aedes fluviatilis (Lutz, 1904) in Ceará, northeastern Brazil

“…They prefer aquatic environments with small amounts of visible organic matter that is exposed to sunlight, and shading factors and aquatic vegetation limit their occurrence. However, due to climatic changes and urbanization processes that alter natural environments, this vector has urbanized and recorded anthropophilic behaviour 9 . Another feature worth mentioning is its ability to share breeding grounds with other culicids, especially Culex quiquefasciatus and Ae.…”

Análise da estrutura populacional de mosquitos Culex quinquefasciatus e Culex nigripalpus (Diptera: Culicidae) utilizando marcadores de microssatélites e análise de morfometria geométrica alar

“…fluviatilis. 73,125 Assim como mencionado para as populações de Cx. quinquefasciatus, a densidade populacional larvária, condições e qualidade de comida e temperatura são fatores que podem influenciar no tamanho alar em insetos 71 .…”

“…Em nosso estudo, somente a população ANH mostrou diferenças significantes no tamanho alar quando comparadas as demais populações. Essas diferenças encontradas para o tamanho das asas podem ser resultados das variadas Triatoma infestans)73,98,125,126 . Foram encontradas evidências de expansão populacional apenas na população ANH, oriunda do parque considerado o mais preservado no estudo onde foi coletada essa espécie.…”