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Although the Pleosporaceae is one of the species-richest families in the Pleosporales, research into less-explored substrates can contribute to widening the knowledge of its diversity. In our ongoing survey on culturable Ascomycota from freshwater sediments in Spain, several pleosporacean specimens of taxonomic interest were isolated. Phylogenetic analyses based on five gene markers (ITS, LSU, gapdh, rbp2, and tef1) revealed that these fungi represent so far undescribed lineages, which are proposed as two novel genera in the family, i.e., Neostemphylium typified by Neostemphylium polymorphum sp. nov., and Scleromyces to accommodate Scleromyces submersus sp. nov. Neostemphylium is characterized by the production of phaeodictyospores from apically swollen and darkened conidiogenous cells, the presence of a synanamorph that consists of cylindrical and brown phragmoconidia growing terminally or laterally on hyphae, and by the ability to produce secondary conidia by a microconidiation cycle. Scleromyces is placed phylogenetically distant to any genera in the family and only produces sclerotium-like structures in vitro. The geographic distribution and ecology of N. polymorphum and Sc. submersus were inferred from metabarcoding data using the GlobalFungi database. The results suggest that N. polymorphum is a globally distributed fungus represented by environmental sequences originating primarily from soil samples collected in Australia, Europe, and the USA, whereas Sc. submersus is a less common species that has only been found associated with one environmental sequence from an Australian soil sample. The phylogenetic analyses of the environmental ITS1 and ITS2 sequences revealed at least four dark taxa that might be related to Neostemphylium and Scleromyces. The phylogeny pre

Penicillium species are common fungi found worldwide from diverse substrates, including soil, plant debris, food products and air. Their diversity in aquatic environments is still underexplored. With the aim to explore the fungal diversity in Spanish freshwater sediments, numerous Penicillium strains were isolated using various culture-dependent techniques. A preliminary sequence analysis of the beta-tubulin (tub2) gene marker allowed us to identify several interesting species of Penicillium, which were later characterized phylogenetically with the barcodes recommended for species delimitation in the genus. Based on the multi-locus phylogeny of the internal transcribed spacer region (ITS) of the ribosomal DNA, and partial fragments of tub2, calmodulin (cmdA), and the RNA polymerase II largest subunit (rpb2) genes, in combination with phenotypic analyses, five novel species are described. These are P. ausonanum in section Lanata-Divaricata, P. guarroi in sect. Gracilenta, P. irregulare in sect. Canescentia, P. sicoris in sect. Paradoxa and P. submersum in sect. Robsamsonia. The study of several isolates from samples collected in different locations resulted in the reinstatement of P. vaccaeorum into section Citrina. Finally, P. heteromorphum (sect. Exilicaulis) and P. tardochrysogenum (sect. Chrysogena) are reported, previously only known from Antarctica and China, respectively.

Curvularia is a Pleosporalean monophyletic genus with a great diversity of species, including relevant phytopathogenic, animal and human pathogenic fungi. However, their microscopic identification is difficult due to overlapping morphological features amongst species. In recent years, multi-locus sequence analysis using the ITS region of the rDNA and fragments of the genes gapdh and tef1 revealed numerous cryptic species, especially in isolates that commonly produced 3-septate conidia. Therefore, based on sequence analysis of the above-mentioned DNA barcodes recommended for species delineation in Curvularia, we propose three novel species, C. panwerrucuksa, C. suttoniae and C. vietnamensis, isolated from soil, human clinical specimens and plant material, respectively, collected in different countries. These new species are morphologically characterised and illustrated in the present study. Curvularia pamverrucuksa differs from its counterparts, C. americana and C. verruculosa, mainly by its narrower conidia. Curvularia suttoniae and C. vietnamensis are closely related to C. petersonii, but the former two have larger conidia.

Background Cutaneous phaeohyphomycosis is an emerging disease in immunocompromised patients, being Alternaria one of the most common genera reported as a causative agent. Species identification is not carried out mainly due to the complexity of the genus. Analysis of the ITS barcode has become standard for fungal identification, but in Alternaria it is only able to discriminate among species-groups or sections. Methods We present three cases of cutaneous infection caused by Alternaria isolates morphologically identified as belonging to section Infectoriae. They have been morphologically characterised and phylogenetically delineated with five molecular markers (ITS, ATPase, gapdh, rpb2 and tef1). Results Mycotic infections have been diagnosed by repeated cultures and histopathological examination in two of the cases. The polyphasic approach has allowed to delineate three new species of Alternaria section Infectoriae, that is A anthropophila, A atrobrunnea and A guarroi. ATPase has been the only locus able to discriminate most of the species (29 out of 31) currently sequenced in this section, including A infectoria the commonest reported species causing alternariosis. Susceptibility test showed different antifungal patterns for the three species, although terbinafine was the most active in vitro drug against these fungi. Conclusions The ATPase gene is recommended as an alternative barcode locus to identify Alternaria clinical isolates in section Infectoriae. Our results reinforce the relevance of identification of Alternaria isolates at the species level and the necessity to carry out antifungal susceptibility testing to determine the most adequate drug for treatment.

Exserohilum includes a number of plant pathogenic, saprobic and clinically relevant fungi. Some of these species are of great importance in human activities, but the genus has never been revised in a phylogenetic framework. In this study, we revise Exserohilum based on available ex-type cultures from worldwide collections, observation of the holotypes and/or protologues, and additional isolates from diverse substrates and geographical origins. Based on nine nuclear loci, i.e., ITS, LSU, act, tub2, cam, gapdh, his, tef1 and rpb2, as well as phenotypic data, the genus and species boundaries are assessed for Exserohilum. Three species, i.e., E. novae-zelandiae, E. paspali and E. sorghicola, are excluded from the genus and reallocated in Sporidesmiella and Curvularia, respectively, whereas E. heteropogonicola and E. inaequale are confirmed as members of Curvularia. Exserohilum rostratum is revealed as conspecific with species previously described in Exserohilum such as E. antillanum, E. gedarefense, E. leptochloae, E. longirostratum, E. macginnisii and E. prolatum. Additionally, E. curvatum is revealed as synonym of E. holmii, and E. fusiforme of E. oryzicola. A total of 11 Exserohilum phylogenetic species are described, illustrated and discussed, including one novel taxon, E. corniculatum. The placements of 15 other doubtful species are discussed, and E. elongatum is validated.

Exserohilum includes a number of plant pathogenic, saprobic and clinically relevant fungi. Some of these species are of great importance in human activities, but the genus has never been revised in a phylogenetic framework. In this study, we revise Exserohilum based on available ex-type cultures from worldwide collections, observation of the holotypes and/or protologues, and additional isolates from diverse substrates and geographical origins. Based on nine nuclear loci, i.e., ITS, LSU, act, tub2, cam, gapdh, his, tef1 and rpb2, as well as phenotypic data, the genus and species boundaries are assessed for Exserohilum. Three species, i.e., E. novae-zelandiae, E. paspali and E. sorghicola, are excluded from the genus and reallocated in Sporidesmiella and Curvularia, respectively, whereas E. heteropogonicola and E. inaequale are confirmed as members of Curvularia. Exserohilum rostratum is revealed as conspecific with species previously described in Exserohilum such as E. antillanum, E. gedarefense, E. leptochloae, E. longirostratum, E. macginnisii and E. prolatum. Additionally, E. curvatum is revealed as synonym of E. holmii, and E. fusiforme of E. oryzicola. A total of 11 Exserohilum phylogenetic species are described, illustrated and discussed, including one novel taxon, E. corniculatum. The placements of 15 other doubtful species are discussed, and E. elongatum is validated.

Bursitis is a common medical condition that can occur either with or without infection. We present a case of fungal olecranon bursitis in an immunocompetent individual caused by the new species Knoxdaviesia dimorphospora. It is a dematiaceous filamentous fungus characterized by the production of two different conidia: hyaline and cylindrical, which rise up from phialidic conidiogenous cells located in the upper part of differentiated and unbranched conidiophores, and pale brown and ellipsoidal conidia produced by phialidic conidiogenous cells which are born directly on hyphae. In addition to its morphological peculiarities, the novelty of the fungus was confirmed by sequence analysis of the internal transcribed spacer (ITS) regions and D1/D2 domains of the 28S of the nuclear rRNA gene. The fungal infection was confirmed by cytological examination and repeated cultures. The infection was resolved by surgical debridement and drainage, and the patient presented a complete functional recovery 3 months later. The in vitro antifungal susceptibility to this new human opportunist is provided, terbinafine being the drug with the most potent activity.

Cryptococcosis is a major fungal disease caused by members of the Cryptococcus gattii and Cryptococcus neoformans species complexes. After more than 15 years of molecular genetic and phenotypic studies and much debate, a proposal for a taxonomic revision was made. The two varieties within C. neoformans were raised to species level, and the same was done for five genotypes within C. gattii. In a recent perspective (K. J. Kwon-Chung et al., mSphere 2:e00357-16, 2017, https://doi.org/10.1128/mSphere.00357-16), it was argued that this taxonomic proposal was premature and without consensus in the community. Although the authors of the perspective recognized the existence of genetic diversity, they preferred the use of the informal nomenclature C. neoformans species complex and C. gattii species complex. Here we highlight the advantage of recognizing these seven species, as ignoring these species will impede deciphering further biologically and clinically relevant differences between them, which may in turn delay future clinical advances.

Arthroderma vanbreuseghemii has been identified molecularly as the causative agent of dermatophytosis in a flock of sheep. It is necessary to explore new treatment alternatives because antifungals are not approved for use on small ruminant animals in the European Union. Antimicrobial photodynamic therapy (aPDT) has been shown to be effective for the treatment of dermatophytosis in humans. It is based on the application of a photosensitizer such as methylene blue (MB) that is activated by visible light to generate reactive oxygen species that are cytotoxic to cells. The use of daylight to perform aPDT (aDL-PDT) avoids the requirement of specific equipment because it uses sunlight to activate the photosensitizer. The aim of our study is to determine the efficacy of aDL-PDT using a 1% MB solution to treat dermatophytosis caused by A. vanbreuseghemii in ewes. Two different topical protocols (1% MB solution spray applications once or twice a week) were assayed in two groups of five infected animals. Twenty-five infected sheep were untreated. All the sheep were exposed to sunlight every day for an approximate duration of 10 h for a total of four weeks. At the end of the study, all the animals treated with aDL-PDT showed the same clinical response to both protocols. In contrast, the animals exposed only to sunlight required an additional two to four weeks before their infections resolved. Conclusion: aDL-PDT with 1% MB solution demonstrates efficacy, safety and efficiency in the treatment of dermatophytosis in sheep.

Four new species of Sporidesmium complex collected on plant debris in different protected areas of the Iberian Peninsula are described and illustrated. Penzigomyces basiacutus is characterized by its obclavate to rostrate conidia with a narrowly obconic-truncate basal cell and verruculose apical cell. Sporidesmium corniculatum is distinguished from other species of the genus by its occasional furcate and only transversely septate conidia and Sporidesmium tunicatum by its obclavate to rostrate, verrucose conidia with an apical mucilaginous sheath tunica. Stanjehughesia obclavorostrata is distinguished by its obclavate to rostrate conidia with the basal cell sometimes darker than the rest.

Bactrodesmiastrum monilioides sp. nov. is described and illustrated from the twig of an unidentified plant collected in Spain. This fungus is characterized by sporodochial conidiomata with moniliform conidiophores, its conidia being solitary, broadly navicular to obovoid, mostly 2-septate, dark brown, with a black band at the septa and basal cell pale brown to brown. Analysis of the ITS region and D1/D2 domains of the LSU of rDNA sequences confirms the placement of this fungus in Bactrodesmiastrum (Sordariomycetes). Because the genus Bactrodesmiastrum was originally characterized by solitary or aggregated conidiophores reduced to a single brown monoblastic conidiogenous cell, an emended description of the genus is provided to accommodate the novel species. A key to species of Bactrodesmiastrum is provided