Diversity of Microbiomes of Culex pipiens f. pipiens and f. molestus from Geographically Distant Collection Sites

This study aimed to investigate the microbiome profile of Culex pipiens, the most abundant mosquito and pathogen vector in the Palearctic, and to find microbiome region and ecotype specificity. The taxon Cx. pipiens includes two ecotypes—pipiens and molestus—and their hybrids, which differ in their epidemiological role. Microbiomes were extracted using bioinformatic analysis from whole-genome datasets of 47 individual Cx. pipiens (pipiens and molestus forms and their hybrids) collected from seven geographically and climatically distinct Russian regions. The dominant phyla and genera were identified, along with a fourfold decrease in microbiome diversity during the transition from larva to adult, and a negative effect of Wolbachia on Cx. pipiens microflora diversity. Microbiome community composition differed significantly between the majority of geographical groups. Analysis of microbial community composition points to anthropogenically altered ecosystems in mosquito habitats. Microbes specific to certain geographical locations were identified. Both forms, pipiens and molestus, share a phylogenetically similar core of dominant taxa but differ in their abundances. A shared core microbiome, present across all samples, is most likely essential for the normal development and survival of Cx. pipiens, and may serve as a target for pathogen-blocking paratransgenesis and region-specific control strategies.