An updated taxonomic framework of Hymenochaetales (Agaricomycetes, Basidiomycota)

Hymenochaetales is one of the fungal orders being mainly composed of wood-inhabiting macrofungi within Agaricomycetes, Basidiomycota.While the species diversity has been well explored, the classification of Hymenochaetales at the family level is still contrary and not fully resolved.In this study, the taxonomic framework of Hymenochaetales is updated with the help of phylogenetic and molecular clock analyses based on six to seven gene regions.Compared with previous papers, the concepts of Hyphodontiaceae and Schizoporaceae are unchanged, while six additional families are emended: the circumscription of the monotypic family Chaetoporellaceae is enlarged by including Echinoporia in this family; a larger concept of Hymenochaetaceae is formally proposed to accommodate members originally in the families Hymenochaetaceae, Neoantrodiellaceae and Nigrofomitaceae, and the genera Basidioradulum and Trichaptum; Repetobasidiaceae and Tubulicrinaceae are reinstated as two monotypic families; the circumscription of Rickenellaceae is reduced to be a monotypic family; and the family name Rigidoporaceae is resurrected to replace its later synonym Oxyporaceae.Besides these eight previously known families, Odonticiaceae is newly erected for Leifia and Odonticium, while five additional monotypic families are also newly erected to make as many genera as possible accommodated at the family level.In addition, Botryodontia, Neoantrodiella and Skvortzoviella are considered to be later synonyms of Rigidoporus, Cyanotrama and Schizocorticium, respectively, and species sampled from these three genera in the current phylogenetic analyses are accordingly transferred.Eventually, a total of 14 families, viz.Chaetoporellaceae, Hymenochaetaceae, Hyphodontiaceae, Odonticiaceae, Peniophorellaceae, Repetobasidiaceae, Resiniciaceae, Rickenellaceae, Rigidoporaceae, Schizocorticiaceae, Schizoporaceae, Sideraceae, Skvortzoviaceae and Tubulicrinaceae accommodating 64 genera, and 19 independent genera are accepted in Hymenochaetales.In conclusion, a more natural taxonomic system of Hymenochaetales is achieved, which is a crucial basis for further exploring species diversity, resource utilization and trait evolution of this fungal order.