Wood staining fungi revealed taxonomic novelties in Pezizomycotina: New order Superstratomycetales and new species Cyanodermella oleoligni

A culture-based survey of staining fungi on oil-treated timber after outdoor exposure in Australia and the Netherlands uncovered new taxa inPezizomycotina.Their taxonomic novelty was confirmed by phylogenetic analyses of multi-locus sequences (ITS, nrSSU, nrLSU, mitSSU,RPB1,RPB2, andEF-1α) using multiplereference data sets. These previously unknown taxa are recognised as part of a new order (Superstratomycetales) potentially closely related toTrypetheliales(Dothideomycetes), and as a new species ofCyanodermella,C. oleoligniinStictidaceae(Ostropales) part of the mostly lichenised classLecanoromycetes. WithinSuperstratomycetalesa single genus namedSuperstratomyceswith three putative species:S.flavomucosus,S. atroviridis, andS. albomucosusare formally described.Monophyly of each circumscribedSuperstratomycesspecies was highly supported and the intraspecific genetic variation was substantially lower than interspecificdifferences detected among species based on the ITS, nrLSU, andEF-1αloci. Ribosomal loci for all members ofSuperstratomyceswere noticeably different from allfungal sequences available in GenBank. All strains from this genus grow slowly in culture, have darkly pigmented mycelia and produce pycnidia. The strains ofC. oleoligniform green colonies with slimy masses and develop green pycnidia on oatmeal agar. These new taxa could not be classified reliably at the class and lowertaxonomic ranks by sequencing from the substrate directly or based solely on culture-dependent morphological investigations. Coupling phenotypic observations withmulti-locus sequencing of fungi isolated in culture enabled these taxonomic discoveries. Outdoor situated timber provides a great potential for culturable undescribedfungal taxa, including higher rank lineages as revealed by this study, and therefore, should be further explored.