Protoellisomyces batrachophilus, gen. et sp. nov., a novel member of the Mucor circinelloides complex causing mucormycosis in a toad.

Mucormycosis is an opportunistic infection that affects humans and animals, being caused by moulds of the order Mucorales. In amphibians, mucormycosis has been well documented in association with Mucor amphibiorum. In this study, histopathological examination of cutaneous nodules in a Japanese common toad (Bufo japonicus) revealed fungal granulomas and sporangia. Phylogenetic analyses of five partial gene fragments, namely the internal transcribed spacer, mini chromosome maintenance complex component 7 (mcm7), largest subunit of RNA polymerase II (rpb1), 20S ribosomal RNA accumulation protein (tsr1), and cyclopropane fatty acylphospholipid synthase (cfs), obtained from the fungus isolated from lesions showed that the isolate (NBRC 117129) formed a highly supported clade with the previously known members of the Mucor circinelloides complex. Based on these morphological and molecular characteristics, we propose a new mucoralean species, Protoellisomyces batrachophilus, gen. et sp. nov.