Diversity and Taxonomy of and Chaetomium-like Fungi from Indoor Environments

During a study of indoor fungi, 145 isolates belonging to were cultured from air, swab and dust samples from 19 countries. Based on the phylogenetic analyses of DNA-directed RNA polymerase II second largest subunit (), β-tubulin (), ITS and 28S large subunit (LSU) nrDNA sequences, together with morphological comparisons with related genera and species, 30 indoor taxa are recognised, of which 22 represent known species, seven are described as new, and one remains to be identified to species level. In our collection, 69 % of the indoor isolates with six species cluster with members of the species complex, representing . The other indoor species fall into nine lineages that are separated from each other with several known chaetomiaceous genera occurring among them. No generic names are available for five of those lineages, and the following new genera are introduced here: with three indoor species, with one indoor species, with four indoor species, with seven indoor species and with two indoor species. The generic concept of is expanded to include and the chaetomium-like species (= ) in which two indoor species are included. The generic concept of is expanded to include several chaetomium-like taxa as well as one indoor species. is recognised as a distinct genus including two indoor taxa. According to this study, is the most abundant indoor species (74/145), followed by (17/145), (6/145) and (5/145). The morphological diversity of indoor as well as the morphological characteristics of the new genera are described and illustrated. This taxonomic study redefines the generic concept of and provides new insight into the phylogenetic relationships among different genera within .