Moniliellomycetes and Malasseziomycetes, two new classes in Ustilaginomycotina

Ustilaginomycotina (Basidiomycota, Fungi) has been reclassified recently based on multiple gene sequence analyses. However, the phylogenetic placement of two yeast-like genera Malassezia and Moniliella in the subphylum remains unclear. Phylogenetic analyses using different algorithms based on the sequences of six genes, including the small subunit (18S) ribosomal DNA (rDNA), the large subunit (26S) rDNA D1/D2 domains, the internal transcribed spacer regions (ITS 1 and 2) including 5.8S rDNA, the two subunits of RNA polymerase II (RPB1 and RPB2) and the translation elongation factor 1-alpha (EF1-alpha), were performed to address their phylogenetic positions. Our analyses indicated that Malassezia and Moniliella represented two deeply rooted lineages within Ustilaginomycotina and have a sister relationship to both Ustilaginomycetes and Exobasidiomycetes. Those clades are described here as new classes, namely Moniliellomycetes with order Moniliellales, family Moniliellaceae, and genus Moniliella; and Malasseziomycetes with order Malasseziales, family Malasseziaceae, and genus Malassezia. Phenotypic differences support this classification suggesting widely different life styles among the mainly plant pathogenic Ustilaginomycotina.