Identification of a new order of root-colonising fungi in the Entorrhizomycota: Talbotiomycetalesord. nov. on eudicotyledons

The recently described fungal phylum Entorrhizomycotawas established solely for the genus Entorrhiza, species of which cause root-galls in Cyperaceaeand Juncaceae. Talbotiomyces calosporus (incertae sedis)shares morphological characteristics and an ecological niche with species of Entorrhiza. We investigated the higher classification of T. calosporusto determine whether it belongs in Entorrhizomycota. Ribosomal DNA sequences showed Talbotiomyces tobe a close relative of Entorrhizaand both taxa form a highly supported monophyletic group. Based on molecular phylogenetic analyses and in congruence with existing morphological and ecological data, Entorrhizaand Talbotiomycesrepresent a deep dichotomy within the Entorrhizomycota. While species of Entorrhizaare characterised by dolipores and occur on monocotyledons, members of Talbotiomycesare characterised by simple pores and are associated with eudicotyledons. This expands the host range of the recently described Entorrhizomycotafrom Poales toother angiosperms. Higher taxa, namely Talbotiomycet alesord. nov. and Talbotiomycetaceaefam. nov., are proposed here to accommodate Talbotiomyces.