Exploratory Survey of Fungal Communities and Cultivable Yeasts Associated with Mosquito Larval Habitats in Italy

Fungi represent recurrent components of mosquito-associated microbial communities, but the larval mycobiota remains far less documented than its bacterial counterpart. Here, we conducted an exploratory survey of fungal communities associated with mosquito larvae collected across central and north-eastern Italy during 2022 and 2023, collecting Aedes albopictus, Aedes koreicus and Culex pipiens larvae and related breeding waters. A subset of 16 larval pools and five water samples was analysed via ITS metabarcoding, while 23 samples were subjected to culture-dependent isolation. Metabarcoding revealed fungal assemblages dominated by Ascomycota and Basidiomycota and Rozellomycota sensu lato, with prominent yeast genera such as Wickerhamomyces, Kurtzmaniella, Candida, Rhodotorula and Metschnikowia. Cultivation yielded 21 yeast isolates assigned to seven distinct species: Candida parapsilosis, Metschnikowia pulcherrima, Barnettozyma californica, Schwanniomyces vanrijiae, Sporobolomyces roseus, Wickerhamomyces anomalus and Rhodotorula paludigena. Overlap between cultured yeast genera and metabarcoding profiles confirmed the complementary nature of the two approaches. This study documents fungal associations in three relevant mosquito species and provides, to our knowledge, the first ITS metabarcoding-based description of the mycobiota in field-collected Ae. koreicus larvae. Although the constrained sampling design precludes definitive inferences regarding host specificity or geographic patterns, the findings provide a baseline for larger studies of mosquito-associated fungal diversity.