Verification of a taxonomy of dermatophytes based on mating results and phylogenetic analyses.

A newly proposed taxonomy of Trichophyton mentagrophytes and related species was introduced and verified with the grounds for the new classification, phylogenetic analysis, and Templeton's cohesive species concept. So-called asexual species were shown to retain sexual ability and different host preferences were shown not to be comparable to different ecological niches. We showed that genealogical concordance phylogenetic species recognition (GCPSR) can be applied to so-called asexual Trichophyton species. The results of GCPSR analysis and mating experiments demonstrated that Arthroderma simii, A. vanbreuseghemii, T. mentagrophytes var. interdigitale, and T. tonsurans may be considered as single phylogenetic species, and that A. benhamiae, T. concentricum, T. verrucosum, and T. mentagrophytes var. erinacei may also be considered as single phylogenetic species. In addition, the conspecificity of three Arthroderma species may also be demonstrated in future. In conclusion, we should not hastily revise the nomenclature based on the phylogenetic tree from only one gene, because different genes can yield different phylogenetic trees. Therefore, we recommend retaining the previous taxonomy until an acceptable taxonomy is proposed.