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Mollisia is a taxonomically neglected discomycete genus ( Helotiales, Leotiomycetes ) of commonly encountered saprotrophs on decaying plant tissues throughout temperate regions. The combination of indistinct morphological characters, more than 700 names in the literature, and lack of reference DNA sequences presents a major challenge when working with Mollisia . Unidentified endophytes, including strains that produced antifungal or antiinsectan secondary metabolites, were isolated from conifer needles in New Brunswick and placed with uncertainty in Phialocephala and Mollisia , necessitating a more comprehensive treatment of these genera. In this study, morphology and multigene phylogenetic analyses were used to explore the taxonomy of Mollisiaceae , including Mollisia , Phialocephala , and related genera, using new field collections, herbarium specimens, and accessioned cultures and sequences. The phylogeny of Mollisiaceae was reconstructed and compared using the nuc internal transcribed spacer rDNA (ITS) barcode and partial sequences of the 28S nuc rDNA (LSU) gene, largest subunit of RNA polymerase II ( RPB1 ), DNA topoisomerase I ( TOP1 ), and the hypothetical protein Lipin/Ned1/Smp2 ( LNS2 ). The results show that endophytism is common throughout the Mollisiaceae lineage in a diverse range of hosts but is infrequently attributed to Mollisia because of a paucity of reference sequences. Generic boundaries within Mollisiaceae are poorly resolved and based on phylogenetic evidence the family included species placed in Acephala , Acidomelania , Barrenia , Bispora , Cheirospora , Cystodendron , Fuscosclera , Hysteronaevia, Loramyces, Mollisia, Neopyrenopeziza , Obtectodiscus, Ombrophila, Patellariopsis , Phialocephala , Pulvinata , Tapesia (= Mollisia ), and Trimmatostroma. Taxonomic novelties included the description of five novel Mollisia species and five novel Phialocephala species and the synonymy of Fuscosclera with Phialocephala , Acidomelania with Mollisia , and Loramycetaceae with Mollisiaceae ., (© 2020 Westerdijk Fungal Biodiversity Institute. Production and hosting by ELSEVIER B.V.)

Xerophilic fungi, especially Aspergillus species, are prevalent in the built environment. In this study, we employed a combined culture-independent (454-pyrosequencing) and culture-dependent (dilution-to-extinction) approach to investigate the mycobiota of indoor dust collected from 93 buildings in 12 countries worldwide. High and low water activity (a w ) media were used to capture mesophile and xerophile biodiversity, resulting in the isolation of approximately 9 000 strains. Among these, 340 strains representing seven putative species in Aspergillus subgenus Polypaecilum were isolated, mostly from lowered a w media, and tentatively identified based on colony morphology and internal transcribed spacer rDNA region (ITS) barcodes. Further morphological study and phylogenetic analyses using sequences of ITS, β-tubulin ( BenA ), calmodulin ( CaM ), RNA polymerase II second largest subunit ( RPB2 ), DNA topoisomerase 1 ( TOP1 ), and a pre-mRNA processing protein homolog ( TSR1 ) confirmed the isolation of seven species of subgenus Polypaecilum , including five novel species: A . baarnensis , A . keratitidis , A . kalimae sp. nov., A . noonimiae sp. nov., A . thailandensis sp. nov., A . waynelawii sp. nov., and A . whitfieldii sp. nov. Pyrosequencing detected six of the seven species isolated from house dust, as well as one additional species absent from the cultures isolated, and three clades representing potentially undescribed species. Species were typically found in house dust from subtropical and tropical climates, often in close proximity to the ocean or sea. The presence of subgenus Polypaecilum , a recently described clade of xerophilic/xerotolerant, halotolerant/halophilic, and potentially zoopathogenic species, within the built environment is noteworthy.

As part of a worldwide survey of the indoor mycobiota, dust was collected from nine countries. Analyses of dust samples included the culture-dependent dilution-to-extinction method and the culture-independent 454-pyrosequencing. Of the 7 904 isolates, 2 717 isolates were identified as belonging to Aspergillus, Penicillium and Talaromyces. The aim of this study was to identify isolates to species level and describe the new species found. Secondly, we wanted to create a reliable reference sequence database to be used for next-generation sequencing projects. Isolates represented 59 Aspergillus species, including eight undescribed species, 49 Penicillium species of which seven were undescribed and 18 Talaromyces species including three described here as new. In total, 568 ITS barcodes were generated, and 391 β-tubulin and 507 calmodulin sequences, which serve as alternative identification markers.

Aspergillus comprises a diverse group of species based on morphological, physiological and phylogenetic characters, which significantly impact biotechnology, food production, indoor environments and human health. Aspergillus was traditionally associated with nine teleomorph genera, but phylogenetic data suggest that together with genera such as Polypaecilum, Phialosimplex, Dichotomomyces and Cristaspora, Aspergillus forms a monophyletic clade closely related to Penicillium. Changes in the International Code of Nomenclature for algae, fungi and plants resulted in the move to one name per species, meaning that a decision had to be made whether to keep Aspergillus as one big genus or to split it into several smaller genera. The International Commission of Penicillium and Aspergillus decided to keep Aspergillus instead of using smaller genera. In this paper, we present the arguments for this decision. We introduce new combinations for accepted species presently lacking an Aspergillus name and provide an updated accepted species list for the genus, now containing 339 species. To add to the scientific value of the list, we include information about living ex-type culture collection numbers and GenBank accession numbers for available representative ITS, calmodulin, β-tubulin and RPB2 sequences. In addition, we recommend a standard working technique for Aspergillus and propose calmodulin as a secondary identification marker.