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Phylogeny and species delimitations in the economically, medically, and ecologically important genus Samsoniella (Cordycipitaceae, Hypocreales).

Samsoniella is a ubiquitous genus of cosmopolitan arthropod-pathogenic fungi in the family Cordycipitaceae. The fungi have economic, medicinal, and ecological importance. Prior taxonomic studies of these fungi relied predominantly on phylogenetic inferences from five loci, namely, the nuclear ribosomal small and large subunits (nr SSU and nr LSU), the 3' portion of translation elongation factor 1 alpha (3P_TEF), and RNA polymerase II subunits 1 and 2 (RPB1 and RPB2). Despite many new species being described, not all of the recognized species inside this group formed well-supported clades. Thus, the search for new markers appropriate for molecular phylogenetic analysis of Samsoniella remains a challenging problem. In our study, we selected the internal transcribed spacer regions of the rDNA (ITS rDNA) and seven gene regions, namely, 3P_TEF, the 5' portion of translation elongation factor 1 alpha (5P_TEF), RPB1, RPB2, γ-actin (ACT), β-tubulin (TUB), and a gene encoding a minichromosome maintenance protein (MCM7), as candidate markers for species identification. Genetic divergence comparisons showed that the ITS, RPB2, ACT, and TUB sequences provided little valuable information with which to separate Samsoniella spp. In contrast, sequence data for 3P_TEF, 5P_TEF, RPB1, and MCM7 provided good resolution of Samsoniella species. The phylogenetic tree inferred from combined data (5P_TEF + 3P_TEF + RPB1 + MCM7) showed well-supported clades for Samsoniella and allowed for the delimitation of 26 species in this genus. The other two species (S.formicae and S.lepidopterorum) were not evaluated, as they had abundant missing data.

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Additions to Hohenbuehelia (Basidiomycota, Pleurotaceae): two new species and notes on H.tristis from northern Thailand.

Two new species and a first geographical record of Hohenbuehelia are described from Thailand. Macroscopic and microscopic descriptions with photoplates, as well as a multigene phylogeny are provided. Hohenbueheliaflabelliformissp. nov. is recognised by large flabelliform basidiomata, densely villose yellowish-white pileus with white hairs near the point of attachment, basidiospores that mostly are ellipsoid in front view and phaseoliform in side view, the absence of cheilocystidia, and a trichoderm pileipellis. Hohenbuehelialageniformissp. nov. is characterised by fleshy basidiomata, velutinous pileus with whitish hairs near the point of attachment and the margin, elsewhere pale greyish-yellow and with only sparse white hairs, pale brown to light brown and mucilaginous context, subglobose basidiospores, lageniform cheilocystidia, an ixotrichoderm pileipellis, and the absence of pileoleptocystidia. Hohenbueheliatristis is characterised by small creamy-white, spathuliform basidiomata that are larger than the type subspecies, minutely pubescent pileus with tiny greyish hairs that disappear when mature, leaving the surface glutinous, faintly translucent and shiny, ellipsoid to sub-ellipsoid basidiospores, lecythiform to sublageniform cheilocystidia, and an ixotrichoderm pileipellis. Hohenbueheliatristis is recorded for Thailand for the first time. Based on the polymorphism observed in part of the nrLSU gene, the presence of two divergent lineages within H.tristis is discussed.

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A new genus Neobelonopsis and two new species of Trichobelonium (Helotiales, Ascomycota) discovered mainly from poaceous grasses native to Asia in Japan.

Mollisioid fungi, represented by Mollisia (Fr.) P. Karst., are characterized by soft, sessile apothecia with globose, dark-celled excipula, hyaline ascospores, and worldwide distribution in temperate regions. Their generic and species delimitation is difficult due to the lack of distinct features, and studies based on DNA sequences are urgently required. Two genera of mollisioid fungi, Belonopsis and Trichobelonium, comprise relatively few species and are recognized by (0-)1-3-septate ascospores, medullary excipulum composed of loosely interwoven hyphae, and calcium oxalate crystals in the excipulum. Specimens of undescribed species that are morphologically assignable to Belonopsis or Trichobelonium were collected from various sites in Japan and their assignment to the proper genera was attempted. According to a molecular phylogenetic analysis involving members of Mollisiaceae based on concatenated sequences of ITS, LSU, and RPB1, eight taxonomic entities were placed in a strongly supported single clade with Mollisiadiesbachiana, separated from the type species of Belonopsis, B.excelsior. A new genus Neobelonopsis was thus proposed to accommodate the undescribed species. In this study, eight new species of Neobelonopsis and two new species of Trichobelonium were described. A new combination was also proposed for M.diesbachiana. The generic distinction of Neobelonopsis and Trichobelonium was supported by molecular analysis. Some additional characteristics to delimit Trichobelonium were identified, such as the presence of anchoring hyphae between the base of the apothecium and subiculum, and the production of abundant crystals and soluble pigments on the colonies. Derivative species of Neobelonopsis were found to have multi-septa in ascospores.

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