摘要：

Naturally occurring microbiota in mosquito larval habitats are among biotic factors which affect the population dynamics of developing larvae. Many microbiota species serve as food items for vector mosquito larvae, and food limitations within habitats adversely affect larval survival, developmental rate, adult fitness, and thereby vector competence. Therefore, identification of microbiota as associates with larvae reveals their relationship between each other as parasites, pathogens, epibionts, or diet organisms. Analysis of associated microbiota species in the dengue vector larval breeding habitats () and the mosquito larval gut content were conducted in Kandy District in Sri Lanka. Study revealed that a total of 22 microbiota species belong to nine phyla (Amoebozoa, Bacillariophyta, Ciliophora, Chlorophyta, Sarcodina, Cyanobacteria/Cyanophyta, Euglenozoa, Ochrophyta/Heterokontophyta, and Rotifera) were encountered from different Ae. aegypti mosquito breeding habitats while 26 microbiota species that belonged to ten phyla were recorded from Ae. albopictus mosquito breeding habitats with one additional phylum Arthropoda. Considering Ae. aegypti breeding habitats, only Philodina citrina in low roof gutters existed as constant species. Considering Aedes albopictus breeding habitats, Volvox aureus in plastic containers, Lecane luna in coconut shells, Phacus pleuronectes in concrete slabs, and Pinnularia sp. in tree holes existed as constant species. The rest of the microbiota existed as common or accidental/rare species in a variety of habitat types. The Shannon-Weiner diversity (21.01 and 19.36) and gamma diversity (eight and eight) of the microbiota associated with Ae. aegypti and Ae. albopictus larvae, respectively, in ponds were found to be higher than other types of breeding habitats recorded during the study. Twelve microbiota species were recorded from larval gut analysis as food organisms of both species of mosquito larvae. However, the distribution of gut microbiota species differed between Ae. aegypti and Ae. albopictus (, ). Identification of microbiota as food items of vector mosquito larvae led to a focus on larval food limitation by introducing food competitors, which could be a potential additional tool for integrated vector control approaches within the country. 1. Introduction In terms of public health, mosquitoes are the most important vectors for diseases, and therefore, studying their ecological and environmental conditions influencing their abundance is important. Mosquito habitat ecology plays an important role to determine the larval densities and species assemblage in a particular breeding habitat [1, 2]. Different types of aquatic habitats are utilized by mosquitoes for oviposition, and many mosquito species tend to select both natural and artificial containers as breeding places [3, 4]. In Sri Lanka, dengue has become a significant socioeconomic and public health burden and Aedes aegypti and Aedes albopictus are widely adapted to urban and suburban environments, acting as vectors of dengue within the country [5]. Water-holding containers were found to be the main larval habitats for Ae. aegypti and Ae. albopictus. Chan et al. [6] have stated that Ae. aegypti breed in indoor-type breeding habitats such as earthenware jars, tin cans, ant traps, rubber tires, bowls, and drums. Immature forms of Ae. albopictus prefer artificial containers with stagnant water and additionally found in tree holes, rock holes, hollow bamboo stumps, and leaf axils [7]. Mosquito distribution, abundance, and individual fitness in breeding habitats are known to be dependent on mainly two factors: biotic and abiotic factors. Biotic factors included the interaction of larvae with other associated macrobiota or microbiota taxa [8–10]. When considering the biotic factors associated with mosquito taxa, there is a diversified naturally occurring microbiota assemblage in mosquito breeding habitats which act as partly potential food organisms, controphic species, competitors, parasites, and/or potential mosquito predators, especially

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