Michal Tomšovský

Drivers of yeast community composition in the litter and soil of a temperate forest.

&NA; Fungi represent a group of soil microorganisms fulfilling important ecological functions. Although several studies have shown that yeasts represent a significant proportion of fungal communities, our current knowledge is based mainly on cultivation experiments. In this study, we used amplicon sequencing of environmental DNA to describe the composition of yeast communities in European temperate forest and to identify the potential biotic and abiotic drivers of community assembly. Based on the analysis of ITS2 PCR amplicons, yeasts represented a substantial proportion of fungal communities ranging from 0.4 to 14.3% of fungal sequences in soil and 0.2 to 9.9% in litter. The species richness at individual sites was 28 ± 9 in soil and 31 ± 11 in litter. The basidiomycetous yeasts dominated over ascomycetous ones. In litter, yeast communities differed significantly among beech‐, oak‐ and spruce‐dominated stands. Drivers of community assembly are probably more complex in soils and comprise the effects of environmental conditions and vegetation.

Delimitation of an almost forgotten species Spongipellis litschaueri (Polyporales, Basidiomycota) and its taxonomic position within the genus

Spongipellis litschaueri, described in 1931 from Austria, is often synonymised with S. delectans in current literature. Morphological and molecular approaches were applied to revise the taxonomic position of this species. The basidiospore dimensions and DNA sequences confirmed differences between S. delectans and S. litschaueri, thus the latter should be kept as a distinct species. However, the relationship between S. litschaueri and its North American kin S. unicolor is complex. Although most of the examined specimens of S. unicolor differ significantly from S. litschaueri in morphological and molecular characters, one American isolate showed markedly high DNA sequence similarity to the European species. Moreover, specimens of S. unicolor from the more or less western USA have larger basidiospores than the others and the respective values are similar to S. litschaueri. Thereby, S. unicolor may split in two taxa where one is closely related to S. litschaueri. Additionally, DNA sequences of a large subunit of the nuclear ribosomal RNA gene were analysed to elucidate the position of Spongipellis within the Polyporales. The results revealed unexpected polyphyly when the generic type S. spumeus fell into a separate lineage from S. delectans, S. litschaueri, S. pachyodon, and S. unicolor. In addition, Tyromyces fissilis occasionally kept in Spongipellis is not related to any species of the genus nor to Tyromyces chioneus, the generic type of Tyromyces. An identification key of European Spongipellis species is provided.

Delimitation of central and northern European species of the Phellinus igniarius group (Basidiomycota, Hymenochaetales) based on analysis of ITS and translation elongation factor 1 alpha DNA sequences

The Phellinus igniarius group comprises several closely related wood-decaying basidiomycetes with poroid hymenophores that are sometimes difficult to identify on a morphological basis. The delimitation of pileate species belonging to the group was the subject of ITS (internal transcribed spacer of ribosomal DNA) and tefa (translation elongation factor 1 alpha) DNA sequence analyses applied to specimens from central and northern Europe. The results confirmed the distinctiveness of P. alni, P. igniarius, P. lundellii, P. nigricans, P. populicola, P. tremulae, and P. tuberculosus in Europe. The specimens of the previously distinguished species P. cinereus were found to be identical with either P. nigricans or P. alni. Thus, Phellinus cinereus does not follow the species criteria of phylogenetic species recognition. In addition, a recently described species, P. neolundellii, was grouped within the P. alni clade. The ITS and tefa analyses produced a different topology for P. populicola and P. igniarius. P. alni had the largest spectrum of hosts, including woody plants from nine families, and records on Aesculus hippocastanum and Ulmus glabra are reported for the first time. P. igniarius s.s. has been collected not only on Salix spp. as expected but also, though rarely, on Populus nigra, and it has been observed once on Malus domestica. The host specificity of the remaining species resembles previous data. An additional analysis of basidiospore dimensions did not reveal any differences between P. alni and P. igniarius, but both are distinguishable from those of P. nigricans.

Taxonomy and phylogeny of European Gymnopus subsection Levipedes (Basidiomycota, Omphalotaceae)

The systematic integrity of European Gymnopus subsect. Levipedes is verified based on anatomic-morphological characters with support from DNA sequences of ITS and translation elongation factor 1-alpha genes. Seven species (G. alpinus, G. aquosus, G. dryophilus – including var. lanipes, G. erythropus, G. fagiphilus, G. hybridus, and G. ocior) belonging to this subsection are included. We clarify the concepts of G. dryophilus and G. ocior, which were occasionally confused in older literature. Due to unavailability of previously selected neotype of G. dryophilus the substitute neotype specimen is selected. Gymnopus dryophilus var. lanipes is confirmed as a variety; no important differences from nominotypical variability were detected. All discriminative characters used for identification of these species are discussed in detail. An identification key is also provided.

Bjerkandera in the Neotropics: phylogenetic and morphological relations of Tyromyces atroalbus and description of a new species

Bjerkandera is a worldwide polypore genus characterized by the pileate grayish basidiomes, often becoming darker when dried, and monomitic hyphal system. Tyromyces atroalbus is a rare Brazilian species re-discovered in recent surveys in São Paulo State. Even though it has been placed in Tyromyces, it presents a characteristic darkening of basidiomes when touched or dried, a feature absent in other species of the genus. In order to understand the evolutionary relations of T. atroalbus with Bjerkandera and Tyromyces and find its proper phylogenetic placement, morphological and molecular studies were carried out. Specimens from Brazil and Mexico were studied morphologically and selected specimens were used for DNA sequence analyses of internal transcribed spacer (ITS) and large subunit (LSU) of ribosomal RNA genes and translation elongation factor 1-alpha genes. Type specimens of T. atroalbus and T. humeana were also morphologically examined to confirm their possible synonymy as well as to confirm the identity of the recent collections. Molecular and morphological characters of T. atroalbus place the species in Bjerkandera. Our results also revealed that the specimens from Brazil and Mexico represent two distinct species. Therefore, the new combination Bjerkandera atroalba and description of new species B. centroamericana is published. In addition, the type study of T. atroalbus and T. humeana supports their synonymy.

Phylloporia yuchengii sp. nov. (Hymenochaetales, Basidiomycota) from Western Tien Shan Mountains of Uzbekistan Based on Phylogeny and Morphology

Abstract Phylloporia yuchengii is newly described and illustrated from alpine ecosystem, Western Tien Shan Mountains in the Tashkent Province of Uzbekistan. This species is distinguished from other Phylloporia species in a combination of hard corky consistency of basidiocarps with thick base (up to 3.5 cm) and azonate pileal surface, pores as 6–8 per mm, a monomitic hyphal system with regularly arranged, interwoven and subparallel generative hyphae, respectively, in context, tomentum and trama, and ellipsoid to oblong-ellipsoid and cyanophilous basidiospores (3.2-4 × 2.3-3 µm). In nLSU-based phylogeny, P. yuchengii nested within the Phylloporia clade and formed a distinct lineage with strong supports. The morphological differences between P. yuchengii and other related Phylloporia species in morphology and geography are discussed.

Insights into the phylogeny of Northern Hemisphere Armillaria: Neighbor-net and Bayesian analyses of translation elongation factor 1-α gene sequences

ABSTRACT Armillaria possesses several intriguing characteristics that have inspired wide interest in understanding phylogenetic relationships within and among species of this genus. Nuclear ribosomal DNA sequence–based analyses of Armillaria provide only limited information for phylogenetic studies among widely divergent taxa. More recent studies have shown that translation elongation factor 1-α (tef1) sequences are highly informative for phylogenetic analysis of Armillaria species within diverse global regions. This study used Neighbor-net and coalescence-based Bayesian analyses to examine phylogenetic relationships of newly determined and existing tef1 sequences derived from diverse Armillaria species from across the Northern Hemisphere, with Southern Hemisphere Armillaria species included for reference. Based on the Bayesian analysis of tef1 sequences, Armillaria species from the Northern Hemisphere are generally contained within the following four superclades, which are named according to the specific epithet of the most frequently cited species within the superclade: (i) Socialis/Tabescens (exannulate) superclade including Eurasian A. ectypa, North American A. socialis (A. tabescens), and Eurasian A. socialis (A. tabescens) clades; (ii) Mellea superclade including undescribed annulate North American Armillaria sp. (Mexico) and four separate clades of A. mellea (Europe and Iran, eastern Asia, and two groups from North America); (iii) Gallica superclade including Armillaria Nag E (Japan), multiple clades of A. gallica (Asia and Europe), A. calvescens (eastern North America), A. cepistipes (North America), A. altimontana (western USA), A. nabsnona (North America and Japan), and at least two A. gallica clades (North America); and (iv) Solidipes/Ostoyae superclade including two A. solidipes/ostoyae clades (North America), A. gemina (eastern USA), A. solidipes/ostoyae (Eurasia), A. cepistipes (Europe and Japan), A. sinapina (North America and Japan), and A. borealis (Eurasia) clade 2. Of note is that A. borealis (Eurasia) clade 1 appears basal to the Solidipes/Ostoyae and Gallica superclades. The Neighbor-net analysis showed similar phylogenetic relationships. This study further demonstrates the utility of tef1 for global phylogenetic studies of Armillaria species and provides critical insights into multiple taxonomic issues that warrant further study.

Extensive characterization of the new genus Rickiopora (Polyporales).

Ceriporiopsis latemarginata and Antrodiella angulatopora are two Neotropical polypores that are very similar morphologically and are characterized by effused-reflexed basidiomes, large angular pores, small ellipsoid to ovoid basidiospores and a monomitic hyphal system with presence of thick-walled hyphae with infrequent clamps. In order to verify the evolutionary relations of C. latemarginata and to find its taxonomic placement, morphological, biological, and phylogenetic studies were carried out, as well as comparisons with Antrodiella s.s. and Ceriporiopsis s.s. Mono- and poly-sporic cultures were obtained and used for mating system and nuclear behaviour studies, as well as for DNA sequence analyses of the internal transcribed spacer and large subunit of ribosomal RNA gene, translation elongation factor 1-alpha gene and RNA polymerase II second largest subunit-like gene. Type specimens of C. latemarginata and A. angulatopora were morphologically examined and their synonymy was confirmed. The results obtained support the description of a new polypore genus Rickiopora in the residual polyporoid clade characterized by a bipolar mating system, an astatocoenocytic nuclear behaviour, and a monomitic hyphal system that display a metachromatic reaction in cresyl blue.

Clearcutting alters decomposition processes and initiates complex restructuring of fungal communities in soil and tree roots

Forest management practices often severely affect forest ecosystem functioning. Tree removal by clearcutting is one such practice, producing severe impacts due to the total reduction of primary productivity. Here, we assessed changes to fungal community structure and decomposition activity in the soil, roots and rhizosphere of a Picea abies stand for a 2-year period following clearcutting compared to data from before tree harvest. We found that the termination of photosynthate flow through tree roots into soil is associated with profound changes in soil, both in decomposition processes and fungal community composition. The rhizosphere, representing an active compartment of high enzyme activity and high fungal biomass in the living stand, ceases to exist and starts to resemble bulk soil. Decomposing roots appear to separate from bulk soil and develop into hotspots of decomposition and important fungal biomass pools. We found no support for the involvement of ectomycorrhizal fungi in the decomposition of roots, but we found some evidence that root endophytic fungi may have an important role in the early stages of this process. In soil, activity of extracellular enzymes also decreased in the long term following the end of rhizodeposition by tree roots.

Re-evaluation of the morphological variability of Microglossum viride and M. griseoviride sp. nov.

Studies in Microglossum viride (Pers.) Gillet revealed that the name was used incorrectly for two similar but different taxa. Analyses of morphological, ecological and molecular (sequences of ITS and LSU region of rRNA gene) characters of type and voucher specimens of M. viride and related taxa resulted in delimitation and description of a new species, Microglossum griseoviride V. Kučera, Lizoň & M. Tomšovský. Lectotypes of Geoglossum viride Pers., and epitype of Geoglossum viride are designated. Species Microglossum minus Velen. and Microglossum lutescens Boud. are confirmed to be conspecific to M. viride.