Emerging infectious fungal diseases such as chytridiomycosis, caused by
Batrachochytrium dendrobatidis and B. salamandrivorans in amphibians, or ophidiomycosis
in reptiles (Ophidiomyces ophiodiicola), are major threats that can drive species or entire
populations to extinction over a short period of time. Besides these well-documented
pathogens, such diseases can be caused by numerous opportunistic fungal species that can
target e.g. immunocompromised individuals from various species of vertebrates. In reptiles,
opportunistic species are mainly documented in captive animals kept in inadequate conditions,
but data remains scarce for wild individuals. In the present study, we isolated and genetically
identified fungal species responsible of skin lesions in wild-caught smooth snakes (Coronella
austriaca) during a field survey targeting endangered reptile species in Switzerland. A total of
18 fungal species were isolated and genetically identified from the lesions of the two wildcaught
snakes and included several species known for being opportunistic pathogens in
vertebrates and infecting mainly immunocompromised individuals, such as Alternaria
infectoria and Rhodotorula spp. It is not possible to establish whether the snakes had such an
issue. However, the exceptional wet and cold conditions experienced in spring 2021 might have
trigger the infections. Indeed, high humidity has been recorded as a predisposing factor for
mycoses in captive reptiles.