Bacterial Communities in Boreal Forest Mushrooms Are Shaped Both by Soil Parameters and Host Identity

Despite recent advances in understanding the microbiome of eukaryotes, little is known about microbial communities in fungi. Here we investigate the structure of bacterial communities in mushrooms, including common edible ones, with respect to biotic and abiotic factors in the boreal forest. Using a combination of culture-based and Illumina high-throughput sequencing, we characterized the bacterial communities in fruitbodies of fungi from eight genera spanning four orders of the class Agaricomycetes (Basidiomycota). Our results revealed that soil pH followed by fungal identity are the main determinants of the structure of bacterial communities in mushrooms. While almost half of fruitbody bacteria were also detected from soil, the abundance of several bacterial taxa differed considerably between the two environments. The effect of host identity was significant at the fungal genus and order level and could to some extent be ascribed to the distinct bacterial community of the chanterelle, representing Cantharellales-the earliest diverged group of mushroom-forming basidiomycetes. These data suggest that besides the substantial contribution of soil as a major taxa source of bacterial communities in mushrooms, the structure of these communities is also affected by the identity of the host. Thus, bacteria inhabiting fungal fruitbodies may be non-randomly selected from environment based on their symbiotic functions and/or habitat requirements.

Comparative mitogenome analysis of two ectomycorrhizal fungi (Paxillus) reveals gene rearrangement, intron dynamics, and phylogeny of basidiomycetes

In this study, the mitogenomes of two Paxillus species were assembled, annotated and compared. The two mitogenomes of Paxillus involutus and P. rubicundulus comprised circular DNA molecules, with the size of 39,109 bp and 41,061 bp, respectively. Evolutionary analysis revealed that the nad4L gene had undergone strong positive selection in the two Paxillus species. In addition, 10.64 and 36.50% of the repetitive sequences were detected in the mitogenomes of P. involutus and P. rubicundulus, respectively, which might transfer between mitochondrial and nuclear genomes. Large-scale gene rearrangements and frequent intron gain/loss events were detected in 61 basidiomycete species, which revealed large variations in mitochondrial organization and size in Basidiomycota. In addition, the insertion sites of the basidiomycete introns were found to have a base preference. Phylogenetic analysis of the combined mitochondrial gene set gave identical and well-supported tree topologies, indicating that mitochondrial genes were reliable molecular markers for analyzing the phylogenetic relationships of Basidiomycota. This study is the first report on the mitogenomes of Paxillus, which will promote a better understanding of their contrasted ecological strategies, molecular evolution and phylogeny of these important ectomycorrhizal fungi and related basidiomycete species.

Phylogenetic affinities of the sequestrate genus Rhodactina (Boletaceae), with a new species, R. rostratispora from Thailand

Rhodactina is a small sequestrate genus in Boletaceae with two described species, R.himalayensis and R.incarnata. Phylogenetic analyses of a three-gene dataset including atp6, tef1 and rpb2 of Rhodactina species along with selected Boletaceae species showed that all Rhodactina species formed a monophyletic clade, sister to the genera Spongiforma and Borofutus in subfamily Leccinoideae with high support. All of the taxa in the clade have a similar chemical reaction in which basidiospores turn purplish, purplish red to violet or violet grey when in contact with potassium hydroxide. The molecular analyses also showed that all Rhodactina specimens collected from Ubon Ratchathani province, northeastern Thailand, belong to a new species. Morphologically, the new species is different from others by having a markedly prominent hilar appendage and a terminal hilum on its basidiospores. Thus, the new species, Rhodactinarostratispora, is introduced with detailed macroscopic and microscopic descriptions and illustrations.

Cacaoporus, a new Boletaceae genus, with two new species from Thailand

We introduce a new genus, Cacaoporus, characterised by chocolate brown to dark brown basidiomata and hymenophore, tubes not separable from the pileus context, white to off-white basal mycelium, reddening when bruised, amygdaliform to ovoid spores and dark brown spore deposit. Phylogenetic analyses of a four-gene dataset (atp6, tef1, rpb2 and cox3) with a wide selection of Boletaceae showed that the new genus is monophyletic and sister to the genera Cupreoboletus and Cyanoboletus in the Pulveroboletus group. Two new species in the genus, C.pallidicarneus and C.tenebrosus are described from northern Thailand. Full descriptions and illustrations of the new genus and species are presented. The phylogeny also confirmed the reciprocal monophyly of Neoboletus and Sutorius, which further support the separation of these two genera.

The mitogenomes of two saprophytic Boletales species (Coniophora) reveals intron dynamics and accumulation of plasmid-derived and non-conserved genes

The order Boletales is a group of fungi with complex life styles, which include saprophytic and ectomycorrhizal mushroom-forming fungi. In the present study, the complete mitogenomes of two saprophytic Boletales species, Coniophora olivacea, and C. puteana, were assembled and compared with mitogenomes of ectomycorrhizal Boletales. Both mitogenomes comprised circular DNA molecules with sizes of 78,350 bp and 79,655 bp, respectively. Comparative mitogenomic analysis indicated that the two saprophytic Boletales species contained more plasmid-derived (7 on average) and unknown functional genes (12 on average) than the four ectomycorrhizal Boletales species previously reported. In addition, the core protein coding genes, nad2 and rps3, were found to be subjected to positive selection pressure between some Boletales species. Frequent intron gain/loss events were detected in Boletales and Basidiomycetes, and several novel intron classes were found in two Coniophora species. A total of 33 introns were detected in C. olivacea, and most were found to have undergone contraction in the C. olivacea mitogenome. Mitochondrial genes of Coniophora species were found to have undergone large-scale gene rearrangements, and the accumulation of intra-genomic repeats in the mitogenome was considered as one of the main contributing factors. Based on combined mitochondrial gene sets, we obtained a well-supported phylogenetic tree for 76 Basidiomycetes, demonstrating the utility of mitochondrial gene analysis for inferring Basidiomycetes phylogeny. The study served as the first report on the mitogenomes of the family Coniophorineae, which will help to understand the origin and evolution patterns of Boletales species with complex lifestyles.

Evolutionary innovations through gain and loss of genes in the ectomycorrhizal Boletales

We aimed to identify genomic traits of transitions to ectomycorrhizal ecology within the Boletales by comparing the genomes of 21 symbiotrophic species with their saprotrophic brown-rot relatives. Gene duplication rate is constant along the backbone of Boletales phylogeny with large loss events in several lineages, while gene family expansion sharply increased in the late Miocene, mostly in the Boletaceae. Ectomycorrhizal Boletales have a reduced set of plant cell-wall-degrading enzymes (PCWDEs) compared with their brown-rot relatives. However, the various lineages retain distinct sets of PCWDEs, suggesting that, over their evolutionary history, symbiotic Boletales have become functionally diverse. A smaller PCWDE repertoire was found in Sclerodermatineae. The gene repertoire of several lignocellulose oxidoreductases (e.g. laccases) is similar in brown-rot and ectomycorrhizal species, suggesting that symbiotic Boletales are capable of mild lignocellulose decomposition. Transposable element (TE) proliferation contributed to the higher evolutionary rate of genes encoding effector-like small secreted proteins, proteases, and lipases. On the other hand, we showed that the loss of secreted CAZymes was not related to TE activity but to DNA decay. This study provides novel insights on our understanding of the mechanisms influencing the evolutionary diversification of symbiotic boletes.

Comparative Genomics of the Ectomycorrhizal Sister Species Rhizopogon vinicolor and Rhizopogon vesiculosus (Basidiomycota: Boletales) Reveals a Divergence of the Mating Type B Locus

Divergence of breeding system plays an important role in fungal speciation. Ectomycorrhizal fungi, however, pose a challenge for the study of reproductive biology because most cannot be mated under laboratory conditions. To overcome this barrier, we sequenced the draft genomes of the ectomycorrhizal sister species Rhizopogon vinicolor Smith and Zeller and R. vesiculosus Smith and Zeller (Basidiomycota, Boletales)-the first genomes available for Basidiomycota truffles-and characterized gene content and organization surrounding their mating type loci. Both species possess a pair of homeodomain transcription factor homologs at the mating type A-locus as well as pheromone receptor and pheromone precursor homologs at the mating type B-locus. Comparison of Rhizopogon genomes with genomes from Boletales, Agaricales, and Polyporales revealed synteny of the A-locus region within Boletales, but several genomic rearrangements across orders. Our findings suggest correlation between gene content at the B-locus region and breeding system in Boletales with tetrapolar species possessing more diverse gene content than bipolar species. Rhizopogon vinicolor possesses a greater number of B-locus pheromone receptor and precursor genes than R. vesiculosus, as well as a pair of isoprenyl cysteine methyltransferase genes flanking the B-locus compared to a single copy in R. vesiculosus Examination of dikaryotic single nucleotide polymorphisms within genomes revealed greater heterozygosity in R. vinicolor, consistent with increased rates of outcrossing. Both species possess the components of a heterothallic breeding system with R. vinicolor possessing a B-locus region structure consistent with tetrapolar Boletales and R. vesiculosus possessing a B-locus region structure intermediate between bipolar and tetrapolar Boletales.

Molecular and morphological analyses confirm Rhizopogon verii as a widely distributed ectomycorrhizal false truffle in Europe, and its presence in South America

The genus Rhizopogon includes species with hypogeous or subepigeus habit, forming ectomycorrhizae with naturally occurring or planted pines (Pinaceae). Species of the genus Rhizopogon can be distinguished easily from the other hypogeous basidiomycetes by their lacunose gleba without columella and their smooth elliptical spores; however, the limit between species is not always easy to establish. Rhizopogon luteolus, the type species of the genus, has been considered one of the species that are more abundant in Europe, as well as it has been cited in pine plantation of North and South America, different parts of Africa, Australia, and New Zealand. However, in this study, based on molecular analyses of the ITS nuclear ribosomal DNA (nrDNA) sequences (19 new sequences; 37 sequences from GenBank/UNITE, including those from type specimens), we prove that many GenBank sequences under R. luteolus were misidentified and correspond to Rhizopogon verii, a species described from Tunisia. Also, we confirm that basidiomes and ectomycorrhizae recently collected in Germany under Pinus sylvestris, as well as specimens from South of Brazil under Pinus taeda belong to R. verii. Thanks to the numerous ectomycorrhizal tips collected in Germany, a complete description of R. verii/P. sylvestris ectomycorrhiza is provided. Moreover, since in this paper the presence of R. verii in South America is here reported for the first time, a short description of basidiomes collected in Brazil, compared with collections located in different European herbaria, is included.

Comparative genomics of Coniophora olivacea reveals different patterns of genome expansion in Boletales

Background

Coniophora olivacea is a basidiomycete fungus belonging to the order Boletales that produces brown-rot decay on dead wood of conifers. The Boletales order comprises a diverse group of species including saprotrophs and ectomycorrhizal fungi that show important differences in genome size.

Results

In this study we report the 39.07-megabase (Mb) draft genome assembly and annotation of C. olivacea. A total of 14,928 genes were annotated, including 470 putatively secreted proteins enriched in functions involved in lignocellulose degradation. Using similarity clustering and protein structure prediction we identified a new family of 10 putative lytic polysaccharide monooxygenase genes. This family is conserved in basidiomycota and lacks of previous functional annotation. Further analyses showed that C. olivacea has a low repetitive genome, with 2.91% of repeats and a restrained content of transposable elements (TEs). The annotation of TEs in four related Boletales yielded important differences in repeat content, ranging from 3.94 to 41.17% of the genome size. The distribution of insertion ages of LTR-retrotransposons showed that differential expansions of these repetitive elements have shaped the genome architecture of Boletales over the last 60 million years.

Conclusions

Coniophora olivacea has a small, compact genome that shows macrosynteny with Coniophora puteana. The functional annotation revealed the enzymatic signature of a canonical brown-rot. The annotation and comparative genomics of transposable elements uncovered their particular contraction in the Coniophora genera, highlighting their role in the differential genome expansions found in Boletales species.

Electronic supplementary material

The online version of this article (10.1186/s12864-017-4243-z) contains supplementary material, which is available to authorized users.

Xerocomellus (Boletaceae) in western North America

Understanding diversity in the genus Xerocomellus in western North America has been obscured by morphological variability, widespread use of species epithets typified by specimens from Europe and eastern North America, misunderstood phylogenetic relationships, and species complexes. We collected extensively and used genetic and morphological data to establish the occurrence of ten Xerocomellus species in western North America. We generated ITS sequences from five type collections and from vouchered representative collections to clarify our understanding of existing species concepts. We describe three new species (Xerocomellus atropurpureus, X. diffractus, and X. salicicola) and propose two new combinations (X. amylosporus and X. mendocinensis), transfer Boletus coccyginus to Hortiboletus, and provide a dichotomous key to species of Xerocomellus in western North America.

Phylloporus and Phylloboletellus are no longer alone: Phylloporopsis gen. nov. (Boletaceae), a new smooth-spored lamellate genus to accommodate the American species Phylloporus boletinoides

The monotypic genus Phylloporopsis is described as new to science based on Phylloporus boletinoides. This species occurs widely in eastern North America and Central America. It is reported for the first time from a neotropical montane pine woodland in the Dominican Republic. The confirmation of this newly recognised monophyletic genus is supported and molecularly confirmed by phylogenetic inference based on multiple loci (ITS, 28S, TEF1-α, and RPB1). A detailed morphological description of P. boletinoides from the Dominican Republic and Florida (USA) is provided along with colour images of fresh basidiomata in habitat, line drawings of the main anatomical features, transmitted light microscopic images of anatomical features and scanning electron microscope images of basidiospores. The taxonomic placement, ecological requirements and distribution patterns of P. boletinoides are reviewed and the relationships with phylogenetically related or morphologically similar lamellate and boletoid taxa such as Phylloporus, Phylloboletellus, Phyllobolites and Bothia are discussed.

New genera, species, and combinations of Boletaceae from Brazil and Guyana

Brasilioporus olivaceoflavidus, gen. et sp. nov., Brasilioporus simoniarum, sp. nov., Neotropicomus australis, gen. et sp. nov., and Nevesoporus nigrostipitatus, gen. et sp. nov. (Boletaceae, Boletales, Basidiomycota), are described from the endangered Atlantic Forest biome of eastern Brazil. New combinations into these new genera are proposed for the Guyanese taxa Xerocomus parvogracilis, Tylopilus rufonigricans, and Tylopilus exiguus. Boletaceae subfamily Chalciporoideae was recircumscribed to include the new genus Nevesoporus. Molecular phylogenetic analyses using a multilocus data set (ITS+28S+TEF1+RPB1+RPB2) from a large taxon set across the Boletaceae justify recognition of the new genera. Morphological, ecological, and DNA sequence data are provided for the new species. A key to known native and introduced bolete species from the Brazilian Atlantic Forest is provided.

An Unexpectedly High Number of New Sutorius (Boletaceae) Species From Northern and Northeastern Thailand

Sutorius is a poroid genus in Boletaceae that typically has chocolate brown to reddish brown or purplish brown basidiomata with a finely scaly stipe and produces a reddish brown spore deposit. During the survey on diversity of boletes in Northern and Northeastern Thailand, several Sutorius collections were obtained. Combined evidence from morphology and phylogenetic analyses of a combined three-gene data set (atp6, tef1 and rpb2) of the Sutorius collections along with selected Boletaceae in the Pulveroboletus group indicated that Thai collections represent seven new Sutorius species. The analyses also indicated that Tylopilus maculatoides belongs in Sutorius. Therefore, the transfer of T. maculatoides to Sutorius is proposed. Full descriptions and illustrations of the seven new species and S. maculatoides are presented in this study. With the seven new species and the new combination, eight of the eleven described Sutorius species are known to occur in Northern and Northeastern Thailand, whereas only one species is known from each of two continents, the Americas and Australia.

Phylogenetic assessment of global Suillus ITS sequences supports morphologically defined species and reveals synonymous and undescribed taxa

The genus Suillus represents one of the most recognizable groups of mushrooms in conifer forests throughout the Northern Hemisphere. Although for decades the genus has been relatively well defined morphologically, previous molecular phylogenetic assessments have provided important yet preliminary insights into its evolutionary history. We present the first large-scale phylogenetic study of the boundaries of each species in the genus Suillus based on the most current internal transcribed spacer (ITS) barcode sequences available inPUBLIC databases, as well as sequencing of 224 vouchered specimens and cultures, 15 of which were type specimens from North America. We found that species boundaries delimited by morphological data are broadly congruent with those based on ITS sequences. However, some species appear to have been described several times under different names, several species groups cannot be resolved by ITS sequences alone, and undescribed taxa are apparent, especially in Asia. Therefore, we elevated S. tomentosus var. discolor to S. discolor; proposed synonymies of S. neoalbidipes with S. glandulosipes, S. borealis with S. brunnescens, Boletus serotinus and B. solidipes with Suillus elbensis, S. lactifluus with S. granulatus, S. himalayensis with S. americanus; and proposed usage of the names S. clintonianus in the place of the North American S. grevillei, S. weaverae for North American S. granulatus, S. ampliporus in the place of the North American S. cavipes, and S. elbensis in place of the North American S. viscidus. We showed that the majority of Suillus species have strong affinities for particular host genera. Although deep node support was low, geographic differentiation was apparent, with species from North America, Eurasia, and Asia often forming their own clades. Collectively, this comprehensive genus-level phylogenetic integration of currently available Suillus ITS molecular data and metadata will aid future taxonomic and ecological work on an important group of ectomycorrhizal fungi.

Hymenogaster macmurphyi and Splanchnomyces behrii are sequestrate species of Xerocomellus from the western United States

Hymenogaster is an ectomycorrhizal genus of brown-spored sequestrate fungi that is related to the mushroom-forming genera Hebeloma and Alnicola (Agaricales). However, because of difficulties in morphological taxonomy of sequestrate fungi, Hymenogaster has become a polyphyletic repository for a variety of unrelated brown-spored sequestrate species. During studies of ectomycorrhizal ecology and sequestrate fungal evolution in the western USA, we encountered specimens of a morphologically unique species. It was originally described as Hymenogaster macmurphyi, but our morphological and molecular analyses indicate that it is not closely related to Hymenogaster. Phylogenetic analyses of multiple gene regions indicate that H. macmurphyi is actually a member of the Boletineae (Boletales, Basidiomycota) and is nested within the epigeous genus Xerocomellus, distantly related to any of the other known genera of sequestrate Boletales. While examining additional herbarium collections, we came upon isotype material of Splanchnomyces behrii, which represents a closely related species. Here we document the morphology and phylogenetic affinities of these unusual sequestrate Boletineae and transfer both species to Xerocomellus as X. macmurphyi and X. behrii. During our study, we also noted that the sequestrate taxon Rhopalogaster transversarius is nested within the epigeous genus Suillus.

Two new species and one new record of the genus Tylopilus (Boletaceae) from Indian Himalaya with morphological details and phylogenetic estimations

Tylopilus himalayanus and T. pseudoballoui are described as new species from two Himalayan states (Sikkim and Uttarakhand) in India. Tylopilus himalayanus is characterised by a unique combination of features: reddish- or brownish-grey to purplish-grey then brown to reddish-brown or darker pileus, absence of olive or violet tinges on stipe surface, angular pores, stipe without reticulum or rarely with a faint reticulum restricted to the very apex, bitter taste of the context and positive macrochemical colour reaction of the stipe context with KOH (dark orange) and FeSO₄ (dark green), medium sized (10.9-14.4 × 3.9-4.9 µm) basidiospores and occurrence under coniferous trees; T. pseudoballoui is distinguished by orange-yellow to brown-yellow sticky pileus, pale yellow pore surface with pinkish hues that turns pale to greyish-orange on bruising; angular pores, stipe concolorous to pileus with pruinose but never reticulate surface, ixocutis pattern of pileipellis and occurrence under broadleaf trees. Another species, T. neofelleus, which was reported earlier from China and Japan, was also collected from Sikkim and reported for the first time from India. All three species are described with morphological details and two-locus based (nrLSU and nrITS) phylogenetic data.

A global view of Gyroporus: molecular phylogenetics, diversity patterns, and new species

Gyroporus (Gyroporaceae, Boletales) is a highly diverse genus of poroid ectomycorrhizal mushrooms with a nearly worldwide distribution. Previous attempts to unravel the diversity within this genus proved difficult due to the presence of semicryptic species and ambiguous results from analysis of ribosomal RNA markers. In this study, we employ a combined morphotaxonomic and phylogenetic approach to delimit species and elucidate geographic and evolutionary patterns in Gyroporus. For phylogenetic analyses, the protein-coding genes atp6 (mitochondrial adenosine triphosphate [ATP] synthase subunit 6) and rpb2 (nuclear second largest subunit of RNA polymerase II) were selected based on their utility in studies of Boletales. We infer several distinct clades, most notably one corresponding to G. castaneus as a speciose Northern Hemisphere group, another unifying G. cyanescens and like entities, and a third group unifying G. longicystidiatus and a New World sister species. Also notable is the recovery of a sister relationship between the cyanescens and longicystidiatus clades. We formally describe five new species of Gyroporus, outline a number of provisional species, and briefly discuss distributional patterns. This study provides an important scaffold for future work on this well-known but poorly understood genus of fungi.

Longistriata flava (Boletaceae, Basidiomycota) - a new monotypic sequestrate genus and species from Brazilian Atlantic Forest

A new monotypic sequestrate genus, Longistriata is described based on collections from the Neotropical forest of Atlantic forest in Paraíba, Northeast Brazil – an area known for its high degree of endemism. The striking features of this new fungus are the hypogeous habit, the vivid yellow peridium in mature basidiomes, broadly ellipsoid basidiospores with a distinct wall that is ornamented with longitudinal striations and lageniform cystidia with rounded apices. Phylogenetic analysis, based on LSU and tef-1α regions, showed that the type species, Longistriataflava, is phylogenetically sister to the monotypic sequestrate African genus Mackintoshia in Boletaceae. Together these two species formed the earliest diverging lineage in the subfamily Zangioideae. Longistriataflava is found in nutrient-poor white sand habitats where plants in the genera Coccoloba (Polygonaceae) and Guapira (Nyctaginaceae) are the only potential ectomycorrhizal host symbionts.

Two new African siblings of Pulveroboletusravenelii (Boletaceae)

This paper sorts out the taxonomy of species affiliated with Pulveroboletusravenelii in the Guineo-soudanian and Zambezian woodlands of Africa. Morphological and genetic characters of African Pulveroboletus collections were studied and compared to those of North American and Asian species. A phylogenetic analysis showed that the African specimens form a subclade, sister to the Asian and American taxa. Although clamp connections have previously never been reported from Pulveroboletus, all specimens of the African subclade show very small clamp connections. Two new African species, Pulveroboletusafricanussp. nov. and P.sokponianussp. nov., are described and illustrated. Comments concerning morphology and identification, as well as distribution and ecology, are given for both species.

Fistulinella ruschii, sp. nov., and a new record of Fistulinella campinaranae var. scrobiculata for the Atlantic Forest, Brazil

Fistulinella is a small genus of boletoid fungi in the subfamily Austroboletoideae in the order Boletales. In this paper, F. ruschii from the Atlantic Forest is proposed as new to science and F. campinaranae var. scrobiculata, known from the Brazilian Amazon forest, is recorded for the first time in the Atlantic Forest. Macro- and microscopic descriptions, molecular data (nuc rDNA ITS1-5.8S-ITS2 and nuc 28S rDNA), photographs of the basidiomata, and scanning electron microscopy images of basidiospores are provided for both species. Based on sampling of six taxa, New World Fistulinella is found to be a strongly supported monophyletic group, but the genus at large is nonmonophyletic.

Additions to the genus Chroogomphus (Boletales, Gomphidiaceae) from Pakistan

With only three published reports, the genus Chroogomphus (Boletales, Gomphidiaceae) is poorly studied in Pakistan. During recent sampling events in Khyber Pakhtunkhawa province, Pakistan, several collections of Chroogomphus were made, representing undescribed taxa. Based on morphological and molecular data, two new species are described: Chroogomphuspakistanicus and C.pruinosus. We present a description and illustrations for both taxa. A molecular phylogenetic reconstruction, based on the internal transcribed spacer (ITS1–5.8S–ITS2) barcode region, shows that C.pakistanicus and C.pruinosus are placed in two different subgenera of Chroogomphus (subg.Chroogomphus and subg. Siccigomphus, respectively).

Boletaceae in China: Taxonomy and phylogeny reveal a new genus, two new species, and a new record

Boletaceae, the largest family in Boletales, has been attracted by mycologists in the world due to its diverse morphology and complex history of evolution. Although considerable work has been done in the past decades, novel taxa are continually described. The current study aimed to introduce three new taxa and one new record of Boletaceae from China. The morphological descriptions, color photographs, phylogenetic trees to show the positions of the taxa, and comparisons with allied taxa are provided. The new genus Hemilanmaoa is unique in the Pulveroboletus group, and Hemilanmaoa retistipitatus was introduced as the type species. It can be distinguished by its bluing basidioma when injured, a decurrent hymenophore, a stipe covered with distinct reticulations, and a fertile stipitipellis. Porphyrellus pseudocyaneotinctus is characterized by its pileipellis consisting of broadly concatenated cells and thin-walled caulocystidia in Porphyrellus. In Phylloporus, Phylloporus biyangensis can be distinguished by its hymenophores that change to blue when injured and yellow basal mycelium. Lanmaoa angustispora, as a new record, is first reported in Northern China. Internal transcribed spacer (ITS), 28S rDNA (28S), translation elongation factor 1-alpha (tef1-α), RNA polymerase II subunit 1 (rpb1), and RNA polymerase II subunit 2 (rpb2) were employed to execute phylogenetic analyses.

The Cedrus-associated truffle Trappeindia himalayensis is a morphologically unique and phylogenetically divergent species of Rhizopogon

In the northwestern Himalayan mountains of India, the hypogeous sequestrate fungus Trappeindia himalayensis is harvested from forests dominated by the ectomycorrhizal tree Cedrus deodara (Himalayan cedar). This truffle has basidiospores that are ornamented with raised reticulation. The original description of Trappeindia himalayensis suggested that the gleba of this species is similar to young specimens of Scleroderma (Boletales), whereas its basidiospores are ornamented with raised reticulation, suggesting a morphological affinity to Leucogaster (Russulales) or Strobilomyces (Boletales). Given this systematic ambiguity, we have generated DNA sequence data from type material and other herbarium specimens and present the first molecular phylogenetic analysis of this unusual Cedrus-associated truffle. Despite the irregular ornamented basidiospore morphology, T. himalayensis is resolved within the genus Rhizopogon (Suillineae, Boletales) and represents a unique lineage that has not been previously detected. All known Rhizopogon species possess an ectomycorrhizal trophic mode, and because of its placement in this lineage, it is likely that Trappeindia himalayensis is an ectomycorrhizal partner of Cedrus deodara. This study highlights the importance of generating sequence data from herbarium specimens in order to identify fungal biodiversity and clarify the systematic relationships of poorly documented fungi.

Reappraisal of the Genus Exsudoporus (Boletaceae) Worldwide Based on Multi-Gene Phylogeny, Morphology and Biogeography, and Insights on Amoenoboletus

The boletoid genera Butyriboletus and Exsudoporus have recently been suggested by some researchers to constitute a single genus, and Exsudoporus was merged into Butyriboletus as a later synonym. However, no convincing arguments have yet provided significant evidence for this congeneric placement. In this study, we analyze material from Exsudoporus species and closely related taxa to assess taxonomic and phylogenetic boundaries between these genera and to clarify species delimitation within Exsudoporus. Outcomes from a multilocus phylogenetic analysis (ITS, nrLSU, tef1-α and rpb2) clearly resolve Exsudoporus as a monophyletic, homogenous and independent genus that is sister to Butyriboletus. An accurate morphological description, comprehensive sampling, type studies, line drawings and a historical overview on the nomenclatural issues of the type species E. permagnificus are provided. Furthermore, this species is documented for the first time from Israel in association with Quercus calliprinos. The previously described North American species Exsudoporus frostii and E. floridanus are molecularly confirmed as representatives of Exsudoporus, and E. floridanus is epitypified. The eastern Asian species Leccinum rubrum is assigned here to Exsudoporus based on molecular evidence, and a new combination is proposed. Sequence data from the original material of the Japanese Boletus kermesinus were generated, and its conspecificity with L. rubrum is inferred as formerly presumed based on morphology. Four additional cryptic species from North and Central America previously misdetermined as either B. frostii or B. floridanus are phylogenetically placed but remain undescribed due to the paucity of available material. Boletus weberi (syn. B. pseudofrostii) and Xerocomus cf. mcrobbii cluster outside of Exsudoporus and are herein assigned to the recently described genus Amoenoboletus. Biogeographic distribution patterns are elucidated, and a dichotomous key to all known species of Exsudoporus worldwide is presented.

Phylogenetic relationships among false truffle genera of Paxillaceae-Alpova, Melanogaster, Neoalpova, and Paralpova, gen. nov

A phylogenetic analysis of nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS), nuc rDNA 28S domains D1-D2 (28S), and the region between conserved domains 6 and 7 of RNA polymerase II second largest subunit (RPB2) from multiple species of Alpova and Melanogaster revealed four major clades, proposed here as distinct genera: Melanogaster, Alpova s. str. containing the type species A. cinnamomeus, Neoalpova for the species around N. rubescens, and the new genus Paralpova, proposed here for P. artikutzensis, sp. nov. Alpova, Neoalpova, and Paralpova form a monophyletic lineage of hypogeous fungi with a pseudoparenchymatic structure in their peridium (at least in the inner layer) that could be interpreted as a single genus, but they are separated due to distinct morphological and ecological traits. Alpova s. str. is employed for species strictly associated with Alnus, lacking a conspicuous odor, and producing relatively small basidiomata and basidiospores <10 µm long. Neoalpova and Paralpova occur under other hosts, present a conspicuous odor, have larger basidiomata and basidiospores than Alpova, and have a prosenchymatic peridiopellis. Finally, Paralpova is characterized by the yellowish gleba, monosporic or bisporic basidia, and basidiospores >15 µm long with a mean length/width ratio (Q_m) of <2.0. In addition, two new species of Neoalpova are proposed: N. arenicola, associated with Mediterranean forests in sandy soils and with spores slightly smaller and wider than those of N. rubescens, and N. montecchii, a cryptic species very similar to N. rubescens but for its putatively smaller peridiopellis elements and its genetic profile.