Nanoglomus plukenetiae , a new fungus from Peru, and a key to small-spored Glomeraceae species, including three new genera in the “ Dominikia complex/clades” Abstract A new arbuscular mycorrhizal fungus was found in an agricultural plantation of Plukenetia volubilis, the inka nut (also called “sacha inchi” or “inka peanut”) in the Amazonia region of San Martín State in Peru. In this site, the inka nut was grown in mixed cultures together with Zea mays and Phaseolus vulgaris. The fungus was propagated in bait and single-species cultures on Sorghum vulgare, Brachiaria brizantha, Medicago sativa, and Plukenetia volubilis as host plants. The fungus differentiates hyaline spores terminally or intercalary on cylindrical to slightly funnel-shaped hyphae, singly or in spore clusters with up to ca. 90 spores per cluster. The spores are bi-layered, (20–)25–36(–45) μm in diameter and show regularly a visible septum at the spore base, despite the small spore and tiny hyphae sizes. Phylogenetically, the new fungus represents a new genus in a separated clade, near to the already known Dominikia clades. It can be distinguished from other species by the small spore size, the characteristics of the spore wall layers, and the clearly visible septum at the spore base, which in Kamienskia and Microkamienskia species has rarely to never been reported, while Dominikia species usually have a higher variability of spore sizes and spore wall characteristics. The fungus is here described under the epithet Nanoglomus plukenetiae, serving as type species of the new genus Nanoglomus. The revision of the species and environmental sequences in the Dominikia clades, based on both morphological and molecular phylogenetic analyses, revealed at least two other new genera: Microdominikia gen. nov., based on D. litorea, and Orientoglomus gen. nov., based on D. emiratia. Finally, in the present study, a key for all small-spored species in the Glomeraceae is included comprising all known Dominikia, Kamienskia, Microdominikia, Microkamienskia, Nanoglomus, Orientoglomus spp., and all small-spored Rhizoglomus spp.

First new species of Fulvifomes (Hymenochaetales, Basidiomycota) from tropical Africa Abstract Fulvifomes is a hymenochaetoid polypore genus currently undergoing re-estimation of its taxonomic and morphological diversity. Numerous new species were described during the last decade but almost exclusively from Neotropics and Eastern Asia. Here, based on morphological and molecular evidence, we describe a new species of Fulvifomes growing on Pseudocedrela kotschyi in Benin. The new species named Fulvifomes yoroui is characterized by perennial, pileate, ungulate basidiomata, and subglobose to globose basidiospores 5.5–6.5 × 4.7–5.6 μm. Analyses of internal transcribed spacer (ITS) and nuclear large subunit rDNA (nLSU) datasets with maximum likelihood and Bayesian phylogenetic inference methods show that F. yoroui represents a distinct lineage within Fulvifomes clade. It is the first time that a new species of Fulvifomes is described based on material from tropical Africa. This finding stimulates further investigations of Fulvifomes in tropical Africa.

Transcriptional heterologous expression of two type III PKS from the lichen Cladonia uncialis Abstract Type III polyketide synthases (PKS) are an under-explored group of enzymes that are responsible for producing a variety of bioactive molecules. In a previous study, we identified two type III PKS genes (t3pks1 and t3pks2) in the lichenizing fungus Cladonia uncialis. Here, we report efforts to functionally characterize these PKS using bioinformatics and heterologous expression. Phylogenetic analysis of t3pks1 indicated that the encoded PKS produces an alkylresorcinol. To estimate the size of the polyketide produced by T3PKS1, crystal structures of fungal type III PKS known to produce alkylresorcinols were examined. A strong correlation (R2 = 0.85) was observed between the active site cavity volume and the size of the largest alkylresorcinol produced by these PKS. Cavity volume measurements of modeled T3PKS1 suggested that this PKS can recruit long (C20) fatty acid-CoA primers to produce a polyketide of approximately 400 g/mol. To functionally characterize both lichen PKS, the t3pks1 and t3pks2 genes were transformed into NSAR1 Aspergillus oryzae. Transcriptional heterologous expression (including intron removal) of both genes was achieved. However, no new metabolites were observed within the host. This study is the first attempt to functionally characterize type III PKS from lichen fungi. Graphical abstract

Two new species of Halophytophthora from Brazil Abstract During a survey of oomycetes in a mangrove area of São Paulo state, Brazil, a high number of isolates of Halophytophthora and related genera were recovered from leaves and water samples. In this study, we analysed the morphology and phylogenetic relationships of the isolates of Halophytophthora along with four ex-types provided by CBS-KNAW Culture Collection. Maximum likelihood and Bayesian analyses of the internal transcribed spacer (ITS) and large subunit (LSU) rDNA regions confirmed previous evidence of the polyphyly of the genus and revealed the presence of two yet undescribed species. The two new species, Halophytophthora souzae and H. insularis, belong to the Halophytophthora sensu stricto clade and are described herein based on their morphology and/or phylogenetic position.

A new dollar spot disease of turfgrass caused by Clarireedia paspali Abstract Clarireedia homoeocarpa causes dollar spot disease (DSD) on turfgrasses and is a problem worldwide. Species diversity was assessed for 62 putative C. homoeocarpa isolates from China by sequencing the nuclear ribosomal internal transcribed spacer (ITS) and the translation elongation factor 1-α (EF-1α) and DNA replication licensing factor (MCM7) genes. The results indicate 17 isolates were C. jacksonii recovered from Poa pratensis and Paspalum vaginatum and 8 were C. monteithiana recovered from P. vaginatum. In addition, 33 isolates, recovered from P. vaginatum, are described here as a new species, Clarireedia paspali sp. nov. Twenty-five of the C. paspali isolates contained a group I intron at the 3′-end of the SSU, clearly differentiating C. paspali isolates with and without the group I intron. The species showed strong geographic distributions which may have important implications for DSD management.

Pseudoplagiostoma myracrodruonis (Pseudoplagiostomataceae, Diaporthales): a new endophytic species from Brazil Abstract Two initially unidentifiable isolates were found when endophytic fungi from healthy leaves of Myracrodruon urundeuva (Anacardiaceae) were being investigated in Brazil. Based on phylogenetic analyses using internal transcribed spacer (ITS) and partial large subunit (LSU) of ribosomal DNA, RNA polymerase II (RPB2), translation elongation factor EF-1 alpha (TEF1), and tubulin (TUB2), the isolates were identified as members of the family Pseudoplagiostomataceae (Diaporthales). In this paper, we introduce a new species, Pseudoplagiostoma myracrodruonis, thus accepting eight species in Pseudoplagiostoma (Pseudoplagiostomataceae). The new species is proposed to accommodate endophytes characterized by a coelomycetous asexual morph, pycnidial conidiomata with lageniform to ampulliform and hyaline to pale brown phialidic conidiogenous cells that produce unicellular, ellipsoid to oblong-cylindrical, hyaline, and guttulate conidia. In the current phylogenetic analysis, P. myracrodruonis is placed in a well-supported clade in Pseudoplagiostoma (Pseudoplagiostomataceae). A discussion about the relationship of Pseudoplagiostoma species is included in the paper.

Morphological characters and molecular data reveal three new species of Fomitopsis (Basidiomycota) Abstract Fomitopsis is an important, cosmopolitan brown-rot genus. Recent phylogenetic analyses showed that Fomitopsis was polyphyletic. During the taxonomic studies of Fomitopsis, three new species were discovered. Phylogenetic analyses carried out based on sequences from the internal transcribed spacer (ITS) regions, the large subunit of nuclear ribosomal RNA gene (nLSU), the small subunit of nuclear ribosomal RNA gene (nSSU), the small subunit of mitochondrial rRNA gene (mtSSU), the second largest subunit of RNA polymerase II (RPB2), and the translation elongation factor 1-α gene (TEF), confirmed the affinities of three new species within Fomitopsis sensu stricto. Fomitopsis caribensis sp. nov. was discovered from Puerto Rico and is characterized by pileate, fragile basidiomata, becoming hard corky upon drying, a white to cream pore surface when fresh, pinkish buff when dry, round to angular and small pores (6–9 per mm), and cylindrical to oblong-ellipsoid basidiospores (6–7.5 × 2.3–3.1 μm). Fomitopsis eucalypticola sp. nov. was collected from Australia. It is characterized by effused-reflexed to pileate basidiomata, cream to salmon pileal surface, cream to yellow pore surface when fresh, becoming buff to clay-buff when dry, occasionally simple-septate skeletal hyphae, long cystidioles (15–36 × 2–5.3 μm), cylindrical to oblong-ellipsoid basidiospores (5.8–9.1 × 2.7–5 μm), and growth on Eucalyptus. Fomitopsis ginkgonis sp. nov. was found from China. It is characterized by its pileate, imbricate, hard corky basidiomata, pinkish buff to cinnamon-buff pore surface, cylindrical basidiospores (7.2–9 × 2.2–3 μm), and growth on living Ginkgo biloba.

Sieverdingia gen. nov., S. tortuosa comb. nov., and Diversispora peloponnesiaca sp. nov. in the Diversisporaceae (Glomeromycota) Abstract Phylogenetic analyses of 18S–ITS–28S nuc rDNA sequences indicated that the arbuscular mycorrhizal fungus originally described as Glomus tortuosum and later transferred to the genus Corymbiglomus represents a separate, previously unrecognized clade at the rank of genus in the family Diversisporaceae (order Diversisporales, phylum Glomeromycota). The analyses located the clade between clades representing the genera Desertispora and Redeckera. Consequently, a new genus, Sieverdingia, was erected, with S. tortuosa comb. nov. The unique morphological feature of S. tortuosa is the formation of glomoid-like spores with a single-layered spore wall covered with a hyphal mantle. Importantly, the erection of Sieverdingia clarified the definition of Corymbiglomus, which currently consists of three species producing glomoid-like spores with one, three- to four-layered spore wall. The features of the innermost layer, which is hyaline, laminate, flexible to semi-flexible, indicate that it is a synapomorphy of Corymbiglomus. The definitions of Corymbiglomus and its species were emended. Moreover, the distribution of S. tortuosa and the three species of Corymbiglomus was discussed based on own studies, literature data, and molecular sequences deposited in public databases. We concluded that the distribution of S. tortuosa and C. globiferum known in environmental studies based on their partial 28S nuc rDNA sequences only may be understated because the main molecular characteristics distinguishing these species reside outside the 28S region. Finally, we described a new species in the genus Diversispora originating from Mediterranean dunes of the Peloponnese peninsula, Greece. The same phylogenetic analyses mentioned above indicated that the closest relative of the new species, producing dark-coloured spores, is D. clara, whose spores are creamy white at most.

Debunking Acroconidiella Abstract Acroconidiella was proposed to accommodate Acroconidiella tropaeoli, a fungal species causing leaf spots on Tropaeolum majus. At the time, it was recognized as deserving to be treated as a distinct genus because, although being somewhat similar to Alternaria, it did not present muriform conidia formed in chains. More recent observations of A. tropaeoli in culture forming acropetal conidial chains, and the recognition of several non-dictioconidial species as belonging to Alternaria, prompted a reappraisal of the genus, starting with the re-examination of the type species. Samples of Acroconidiella tropaeoli, and also of Acroconidiella trisepta, were recollected in Brazil, and a study involving an analysis of their morphology, under light microscopy and SEM, and a molecular phylogenenetic analysis was performed. A multi-gene phylogeny, including the large subunit of the nrDNA (nc LSU rDNA), internal transcribed spacer (ITS) region, translation elongation factor 1-α (EF1), and polymerase II second largest subunit (RPB2), placed A. tropaeoli within Alternaria, close to A. sonchi and A. cinerariae. The ITS and nc LSU rDNA phylogenetic study of A. trisepta placed it within Dendryphiella. The new combination Dendryphiella trisepta comb. nov is proposed to accommodate A. trisepta. Nevertheless, the new name Alternaria obtusa is proposed for Acroconidiella tropaeoli since it could not be recombined into Alternaria tropaeoli because this name is already in use for another valid (and distinct) species in this genus described from India. This study showed that Acroconidiella is an artificial genus which is now rejected, since its type species belongs to Alternaria—which has nomenclatural priority over Acroconidiella. Other species placed in Acroconidiella, given below, await reappraisal in order to determine their correct taxonomic affinity.

Botryosphaerialean fungi causing canker and dieback of tree hosts from Mount Yudu in China Abstract The order Botryosphaeriales includes many latent fungal pathogens with a wide range of woody hosts. The taxonomy of these pathogens has been difficult due to the use of poorly informing markers in phylogenetic analyses and the lack of good morphological characters. Many genera and families in this order have not yet been systematically studied in different hosts and from different regions. In this study, a total of 29 fungal strains from the Aplosporellaceae and Botryosphaeriaceae were isolated from branches or twigs with symptoms of canker and dieback disease in Mount Yudu of China. Morphology and multigene analyses (ITS, LSU and TEF1-α) indicated five distinct lineages, including Aplosporella javeedii, Botryosphaeria dothidea, Diplodia quercicola sp. nov., Phaeobotryon aplospora sp. nov. and Phaeobotryon rhois. Diplodia quercicola is characterized by multiloculate conidiomata, producing oblong to cylindrical, thick-walled, hyaline, aseptate conidia. Phaeobotryon aplospora is characterized by pulvinate, multiloculate conidiomata, producing ellipsoid to oblong, brown, aseptate conidia. The new species differ from related species phylogenetically and ecologically and in morphological features.