Abstract

High mortality was observed in a group of juvenile Wagler’s vipers (WV; Tropidolaemus wagleri) with the consistent finding of widespread retained shed. Skin biopsies were obtained from one viper and revealed a novel Paranannizziopsis species based on phenotypic and molecular tools. Histologic examination revealed hyperplastic, hyperkeratotic, and crusting epidermitis with intralesional fungi. These WV are housed in a room with tentacled snakes (TS; Erpeton tentaculatum) where the terrestrial WV are housed singly in 30.5x30.5x30.5 cm glass terraria with an average temperature of 25.2°C and relative humidity of 63.2%, while TS are housed as a pair in a 56.8-L fully aquatic tank with average water temperature of 25.2°C. The TS in this collection have a history of intermittent skin lesions since 2011. Skin biopsies collected from one TS approximately 2 mo after biopsies collected from the WV revealed a Paranannizziopsis isolate genetically identical to that found in the WV and a similar histologic appearance. Susceptibility testing indicated that terbinafine and voriconazole had potent activity against these isolates. Sequencing confirmed a new species, which was named Paranannizziopsis tardicrescens (Mycobank accession 818644), characterized by slow growth on all media, growth at 35°C, hydrolysis of milk solids on bromcresol purple-milk solids-glucose agar, and lacking ascomatal initials and undulate hyphal branches. The route of transmission is unknown, but this fungus is suspected to be present in the environment and transmissible by fomites. Further investigation is needed to understand the natural history of this fungal species.

Acknowledgments

The authors would like to thank Dr. Jean Paré for providing expert guidance on Paranannizziopsis fungi during the initial investigation of these cases and Fort Worth Zoo’s veterinary technicians and ectotherm department staff for assistance during procedures, administering treatments, and routine care of these animals.