Composition and Genetic Diversity of Mosquitoes (Diptera: Culicidae) on Islands and Mainland Shores of Kenya’s Lakes Victoria and Baringo

Abstract

The Lake Baringo and Lake Victoria regions of Kenya are associated with high seroprevalence of mosquito-transmitted arboviruses. However, molecular identification of potential mosquito vector species, including morphologically identified ones, remains scarce. To estimate the diversity, abundance, and distribution of mosquito vectors on the mainland shores and adjacent inhabited islands in these regions, we collected and morphologically identified adult and immature mosquitoes and obtained the corresponding sequence variation at cytochrome c oxidase 1 (COI) and internal transcribed spacer region 2 (ITS2) gene regions. A total of 63 species (including five subspecies) were collected from both study areas, 47 of which have previously been implicated as disease vectors. Fourteen species were found only on island sites, which are rarely included in mosquito diversity surveys. We collected more mosquitoes, yet with lower species composition, at Lake Baringo (40,229 mosquitoes, 32 species) than at Lake Victoria (22,393 mosquitoes, 54 species). Phylogenetic analysis of COI gene sequences revealed Culex perexiguus and Cx. tenagius that could not be distinguished morphologically. Most Culex species clustered into a heterogeneous clade with closely related sequences, while Culex pipiens clustered into two distinct COI and ITS2 clades. These data suggest limitations in current morphological identification keys. This is the first DNA barcode report of Kenyan mosquitoes. To improve mosquito species identification, morphological identifications should be supported by their molecular data, while diversity surveys should target both adults and immatures. The diversity of native mosquito disease vectors identified in this study impacts disease transmission risks to humans and livestock.

DNA barcodes and evidence of cryptic diversity of anthropophagous mosquitoes in Quintana Roo, Mexico

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DNA Barcoding Reveals Cryptic Diversity in the Underestimated Genus Triplophysa (Cypriniformes: Cobitidae, Nemacheilinae) from the Northeastern Qinghai-Tibet Plateau

“…At the same time, using just one standardized barcode gene is not a perfect way to identify species, because their lower nucleotide sequence differences may be ignored (Ratnasingham and Hebert, 2013). It is necessary to combine nuclear markers with ecological and biological data (Ajamma et al, 2016;Waldir et al, 2018;Durand et al, 2017;Wang et al, 2018) and expand the survey area and number of species to evaluate the species boundary of the plateau loach genus. This study provides a basis for protecting the biodiversity of plateau loach.…”

Molecular Identification of ten species of stored-product psocids through microarray method based on ITS2 rDNA

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