Unroughing the cat's tongue mushrooms: Four new species of Pseudohydnum from Brazil based on morphological and molecular phylogenetic evidence.

Pseudohydnum, commonly known as cat's tongue mushrooms, is a monophyletic assemblage within Auriculariales, which encompasses species with gelatinous basidiomata, spathulate, flabellate, or shell-shaped pileus, hydnoid hymenophore, globose to ellipsoidal basidiospores, and longitudinally cruciate-septate basidia. According to the available literature, 16 species have been described in Pseudohydnum, mostly represented in temperate-boreal forests of the Northern Hemisphere. However, the limited morphological, molecular, and ecological information, especially from the Southern Hemisphere ecosystems, does not presently allow a reliable assessment of its taxonomic boundaries nor provide a complete picture of the species diversity in the genus. In an ongoing effort to examine specimens collected in dense and mixed ombrophilous forest fragments (Atlantic Rainforest domain) from Southeastern and Southern Brazil, additional taxa assigned to Pseudohydnum were identified. Four new species are recognized based mostly on characters of the pileus surface, stipe, hymenium, and basidiospores. Molecular phylogenetic analyses based on nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS barcode), partial nuc rDNA 28S, and partial RNA polymerase II largest subunit (RPB1) sequences supported the description of these new taxa. Here, we propose Pseudohydnum brasiliense, P. brunneovelutinum, P. cupulisnymphae, and P. viridimontanum as new species. Morphological descriptions, line drawings, habitat photos, and comparisons with closely related taxa are provided. A dichotomous key for identification of currently known Southern Hemisphere Pseudohydnum species is presented.

Four new species of Russula from the Xizang Autonomous Region and other provinces of China.

Russula is the largest genus in the Russulales and is widespread throughout the world. Almost all Russula species are known to be ectomycorrhizal with high ecological and edible values, and some are lethal poisonous. In this study, four new species belonging to the subgenus Russula crown clade are identified based on morphological and phylogenetic evidence from the Xizang Autonomous Region and other provinces of China. Morphologically, Russula paragraveolens (sect. Polychromae, subsect. Xerampelinae) is mainly characterised by a cherry red to blood red pileus centre, a reddish orange pileus margin; R. pseudograveolens (sect. Polychromae, subsect. Xerampelinae) is characterised by a violet brown to brownish red pileus centre, a pale red to pastel red pileus margin and short basidia; R. shigatseensis (sect. Flavisiccantes, subsect. Lepidinae) is characterised by a brownish orange to madder red pileus centre, pinkish red pileus margin, and having lateral branches or branches of hyphal terminations in pileipellis; R. yadongensis (sect. Tenellae, subsect. Laricinae) is characterised by a dark purplish red pileus centre with brownish purple tints and having isolated to clustered spines of spore ornamentations. Their distinct taxonomic status is confirmed by the positions of the four new species in both the ITS and 4-locus (nucLSU, mtSSU, rpb2, tef1) phylogenetic trees.

Concordance of multigene genealogy along with morphological evidence unveils five novel species and two new records of boletoid mushrooms (fungi) from India.

Agaricales, Russulales and Boletales are dominant orders among the wild mushrooms in Basidiomycota. Boletaceae, one of the major functional elements in terrestrial ecosystem and mostly represented by ectomycorrhizal symbionts of trees in Indian Himalaya and adjoining hills, are extraordinarily diverse and represented by numerous genera and species which are unexplored or poorly known. Therefore, their hidden diversity is yet to be revealed. Extensive macrofungal exploration by the authors to different parts of Himalaya and surroundings, followed by through morphological studies and multigene molecular phylogeny lead to the discovery of five new species of wild mushrooms: Leccinellum bothii sp. nov., Phylloporus himalayanus sp. nov., Phylloporus smithii sp. nov., Porphyrellus uttarakhandae sp. nov., and Retiboletus pseudoater sp. nov. Present communication deals with morphological details coupled with illustrations and phylogenetic inferences. Besides, Leccinellum sinoaurantiacum and Xerocomus rugosellus are also reported for the first time from this country.

Identification of two genes essential for basidiospore formation during the postmeiotic stages in Pleurotus ostreatus.

A sporeless strain is an important breeding target in the mushroom industry. However, basidiospore production in the oyster mushroom Pleurotus ostreatus has been shown to be impaired by single-gene mutations in only two meiosis-related genes, mer3 and msh4. This study proposed a strategy for identifying the genes essential for basidiospore formation after meiotic division to determine new targets for molecular breeding. RNA-seq analysis was performed to identify P. ostreatus genes that are specifically expressed in the gill tissue of fruiting bodies, where basidiospore formation occurs. Transcriptome data during fruiting development of Coprinopsis cinerea, in which the meiotic steps progress synchronously, were then used to identify genes that are active in the postmeiotic stages. Based on these comparative analyses, five P. ostreatus genes were identified. Plasmids containing expression cassettes for hygromycin B-resistance screening, Cas9, and single-guide RNA targeting each gene were introduced into the protoplasts of dikaryotic strain, PC9×#64, to generate dikaryotic gene disruptants. Among the obtained transformants, three dikaryotic pcl1 disruptants and two cro6c disruptants did not produce basidiospores. Microscopic analyses indicated that spore formation was arrested at particular stages in these gene disruptants. These results indicate that these two genes are essential for mature spore formation in this fungus.

Visualizing organelles with recombinant fluorescent proteins in the white-rot fungus Pleurotus ostreatus.

White-rot fungi secrete numerous enzymes involved in lignocellulose degradation. However, the secretory mechanisms or pathways, including protein synthesis, folding, modification, and traffic, have not been well studied. In the first place, few experimental tools for molecular cell biological studies have been developed. As the first step toward investigating the mechanisms underlying protein secretion, this study visualized organelles and transport vesicles involved in secretory mechanisms with fluorescent proteins in living cells of the white-rot fungus Pleurotus ostreatus (agaricomycete). To this end, each plasmid containing the expression cassette for fluorescent protein [enhanced green fluorescent protein (EGFP) or mCherry] fused with each protein that may be localized in the endoplasmic reticulum (ER), Golgi, or secretory vesicles (SVs) was introduced into P. ostreatus strain PC9. Fluorescent microscopic analyses of the obtained hygromycin-resistant transformants suggested that Sec13-EGFP and Sec24-EGFP visualize the ER; Sec24-EGFP, mCherry-Sed5, and mCherry-Rer1 visualize the compartment likely corresponding to early Golgi and/or the ER-Golgi intermediate compartment; EGFP/mCherry-pleckstrin homology (PH) visualizes possible late Golgi; and EGFP-Seg1 and mCherry-Rab11 visualize SVs. This study successfully visualized mitochondria and nuclei, thus providing useful tools for future molecular cell biological studies on lignocellulose degradation by P. ostreatus. Furthermore, some differences in the Golgi compartment or apparatus and the ER-Golgi intermediate of P. ostreatus compared to other fungi were also suggested.

Luteodorsum huanglongense (Gomphaceae, Gomphales), a New Genus and Species of Gomphoid Fungus from the Loess Plateau, Northwest China.

During an investigation of the macrofungal flora in the Huanglong Mountains of the Loess Plateau, northwest China, a unique gomphoid fungus was discovered and collected. After morphological identification and molecular phylogenetic analyses, a new genus named Luteodorsum and its type species, L. huanglongense, were proposed. Phylogenetic analyses were conducted using datasets of nuclear ribosomal DNA 28S large subunit (LSU), mitochondrial (mt) adenosine triphosphatase (ATPase) subunit 6 (atp6), and mt small-subunit rDNA (mtSSU). The results confirmed that L. huanglongense forms an independent clade within Gomphales, with full maximum likelihood bootstrap support (MLBS), maximum parsimony bootstrap support (MPBS), and Bayesian posterior probability (BPP). L. huanglongense is characterized by its sandy-brown, orange-brown, or coffee-brown color; clavate to infundibuliform shape; wrinkled and ridged hymenophore; ellipsoid to obovoid warted basidiospores; cylindrical to clavate flexuous pleurocystidia; and crystal basal mycelium. Overall, this study contributes to the growing body of knowledge on the diversity and evolution of Gomphales and provides valuable insights into the unique fungal flora found in the Huanglong Mountains.

Genomic Diversity and Phenotypic Variation in Fungal Decomposers Involved in Bioremediation of Persistent Organic Pollutants.

Fungi work as decomposers to break down organic carbon, deposit recalcitrant carbon, and transform other elements such as nitrogen. The decomposition of biomass is a key function of wood-decaying basidiomycetes and ascomycetes, which have the potential for the bioremediation of hazardous chemicals present in the environment. Due to their adaptation to different environments, fungal strains have a diverse set of phenotypic traits. This study evaluated 320 basidiomycetes isolates across 74 species for their rate and efficiency of degrading organic dye. We found that dye-decolorization capacity varies among and within species. Among the top rapid dye-decolorizing fungi isolates, we further performed genome-wide gene family analysis and investigated the genomic mechanism for their most capable dye-degradation capacity. Class II peroxidase and DyP-type peroxidase were enriched in the fast-decomposer genomes. Gene families including lignin decomposition genes, reduction-oxidation genes, hydrophobin, and secreted peptidases were expanded in the fast-decomposer species. This work provides new insights into persistent organic pollutant removal by fungal isolates at both phenotypic and genotypic levels.

Novelties in Macrofungi of the Tropical Montane Cloud Forest in Mexico.

The tropical montane cloud forest in Mexico is the most diverse and threatened ecosystem. Mexican macrofungi numbers more than 1408 species. This study described four new species of Agaricomycetes (Bondarzewia, Gymnopilus, Serpula, Sparassis) based on molecular and morphological characteristics. Our results support that Mexico is among the most biodiverse countries in terms of macrofungi in the Neotropics.

Taxonomy and Phylogeny of Corticioid Fungi in Auriculariaceae (Auriculariales, Basidiomycota): A New Genus, Five New Species and Four New Combinations.

The Auriculariaceae accounts for most of the species in the Auriculariales, and all species in the family are wood-decaying fungi with gelatinous, crustaceous, or woody basidiomes. Many new taxa were published recently, but the taxonomy and phylogeny of the corticioid species in the Auriculariaceae are far from resolved. We undertook a comprehensive taxonomic and phylogenetic study of the family with emphasis on corticioid specimens collected from East and Southeast Asia. Phylogenetic analyses on concatenated ITS and 28S rDNA sequences of representative taxa of the Auriculariaceae and the genera Eichleriella and Heteroradulum were carried out that resolved five new lineages. Heterocorticium gen. nov. is established for two species with resupinate coriaceous basidiomes with smooth, pigmented hymenophores. Five new species, H. bambusicola (generic type), H. latisporum, Eichleriella alpina, E. bambusicola, and Heteroradulum maolanense, are described and illustrated. In addition, Heterochaete delicata, H. discolor, and H. sinensis are transferred to Eichleriella, whereas H. roseola is regarded as a synonym of Kneiffia discolor (= H. discolor). Eichleriella aculeobasidiata is treated as a synonym of Heterochaete sinensis (= E. sinensis). Heterochaete mussooriensis is transferred to Heteroradulum with Heteroradulum semis as a heterotypic synonym. The present study contributes to the understanding of species diversity, taxonomy, and phylogeny of corticioid fungi in Asia.

Overview of the European species of the genus Clitocella (Entolomataceae, Agaricales) with notes on extralimital taxa.

A revision, based on morphological and multigene analysis, of the Clitocella species currently present in Europe is provided. Portions of nrITS rDNA, nr28S rDNA (LSU), RNA polymerase II second largest subunit (RPB2), translation elongation factor 1-alpha (EF-1α), and ATPase subunit 6 (ATP6), were used to sort out the relationships of the species within the genus. Three subgenera were recognized: Clitocella subg. Clitocella encompassing C. popinalis, C. colorata, C. mundula, C. nigrescens, C. obscura and the new species C. solaris from Switzerland; the new Clitocella subg. Paraclitopilus including C. fallax and C. blancii; and the new Clitocella subg. Rhodopleurella for accommodating C. termitophila, a peculiar entity characterized by a pleurotoid habit and growing on decaying, abandoned termite nests in the Dominican Republic. Clitocella colorata originally described from China is here reported and described for the first time in Europe (Italy and Estonia). Rhodocybe cupressicola and Clitopilus ammophilus are reduced to later synonyms of Rhodopaxillus nigrescens; similarly, Clitopilus amarus is treated as a later synonym of Omphalia fallax while Rhodocybe amarella and R. ochraceopallida of Rhodopaxillus blancii. Finally, Austrian and Swedish herbarium collections identified as Rhodocybe, a doubtful taxon considered by several modern authors occasionally as either a similar but distinct species from R. popinalis or as a dwarfish, puny and odourless form of R. popinalis, have been proved to be R. tugrulii, a species recently described from Turkey and Estonia, and also later reported from Italy and USA. Citation: Vizzini A, Consiglio G, Marchetti M. 2023. Overview of the European species of the genus Clitocella (Entolomataceae, Agaricales) with notes on extralimital taxa. Persoonia 50: 123-157. https://doi.org/10.3767/persoonia.2023.50.04.

Taxonomy and Multi-Gene Phylogeny of Poroid Panellus (Mycenaceae, Agaricales) With the Description of Five New Species From China.

Panellus is an Agaricales genus with both lamellate and poroid hymenophore. The poroid species are readily overlooked because of their tiny basidiocarps. The Chinese samples of poroid Panellus are studied, and five species, namely Panellus alpinus, Panellus crassiporus, Panellus longistipitatus, Panellus minutissimus, and Panellus palmicola are described as new species based on morphology and molecular phylogenetic analyses inferred from an nrITS dataset and a multi-gene dataset (nrITS + nrLSU + mtSSU + nrSSU + tef1). Panellus alpinus is characterized by its round to ellipsoid pores measuring 4-6 per mm and oblong ellipsoid basidiospores measuring 4.8-6 µm × 2.8-3.6 µm; P. crassiporus differs from other poroid species in the genus by the irregular pores with thick dissepiments and globose basidiospores measuring 8-9.8 µm × 6.9-8 µm; P. longistipitatus is distinguished by its long stipes, pyriform cheilocystidia, and broadly ellipsoid to subglobose basidiospores measuring 7-9.8 µm × 5-7 µm; P. minutissimus is characterized by its tiny and gelatinous basidiocarps, 5-20 pores per basidiocarp, and ellipsoid basidiospores measuring 6-8 µm × 3.2-4.2 µm; P. palmicola is characterized by its round pores measuring 2-4 per mm, the presence of acerose basidioles, and globose basidiospores measuring 7-9.5 µm × 6.2-8.2 µm. An identification key to 20 poroid species of Panellus is provided.

Neohygrocybe pseudoingrata, a new grassland species from Slovakia and the Czech Republic.

Neohygrocybe pseudoingrata, a new waxcap species known from Slovakia and the Czech Republic, is characterised by its pale greyish coloured and often robust basidiomata (or sporocarps), nitrous smell, context without colour changes, hollow, contorted and compressed stipe and smooth or slightly fibrillose pileus surface. Based on morphology and DNA analysis of ITS and LSU sequences of the collected specimens, N. pseudoingrata belongs to Neohygrocybe sect. Neohygrocybe together with N. ovina, N. nitrata and N. ingrata. Collections of N. pseudoingrata form a well-supported clade in phylogenetic trees. Citation: Fuljer F, Zajac M, Boertmann D, Szabóová D, Kautmanová I (2022). Neohygrocybe pseudoingrata, a new grassland species from Slovakia and the Czech Republic. Fungal Systematics and Evolution 9: 11-17. doi: 10.3114/fuse.2022.09.02.

Alloexidiopsis gen. nov., A Revision of Generic Delimitation in Auriculariales (Basidiomycota).

Auriculariales is a fungal order with highly diverse morphological traits of basidiomes, which partially leads to a poor understanding of its taxonomic system at the generic level. To identify our recently collected specimens of Auriculariales to a species level, we perform a comprehensive phylogenetic analysis of the generic relationships in Auriculariales. In association with morphological characteristics, a new genus Alloexidiopsis belonging to Auriculariaceae is erected with two new species, namely, A. australiensis and A. schistacea. Moreover, Exidiopsis calcea separated from the generic type E. effusa and Heteroradulum niveum and H. yunnanense recently inaccurately described as members of Heteroradulum are recovered in the clade of Alloexidiopsis. These three species are thus transferred to this new genus. One collection of Exidiopsis grisea also falls in the clade of Alloexidiopsis, whereas another collection of this species is separated far from Alloexidiopsis and E. effusa. Since we have no collection to confirm the species identity of E. grisea, its generic position is uncertain. The main taxonomic morphological differences among Alloexidiopsis and related corticioid genera in Auriculariales are summarized. A key to all the five accepted species of Alloexidiopsis is provided. As two unnamed lineages exist in Alloexidiopsis besides the abovementioned five species, it is assumed that more new species will be revealed from this genus under its current circumscription.

Gomphocantharellus, a new genus of Gomphales.

The genus Gomphocantharellus and species Gomphocantharellus cylindrosporus are proposed as new based on morphological assessments and molecular phylogenetic evidence inferred from nucleotide sequences of mitochondrial (mt) adenosine triphosphate (ATPase) subunit 6 (atp6) and mt small subunit rDNA (mtSSU). Basidiomes of G. cylindrosporus are characterized by the peach to pinkish orange color, cantharelloid habit with a gill-like hymenophore with obtuse edges, smooth and cylindrical to allantoid basidiospores, and cylindrical to narrowly clavate flexuous pleurocystidia. The species resembles a species of Cantharellus but differs from the latter by the cylindrical basidiospores. Phylogenetic analyses confirm the placement of Gomphocantharellus as an independent lineage within the order Gomphales.

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.

Exploring Agaricomycetes from the Paranaense rainforest (Misiones, Argentina) as an unconventional source of fibrinolytic enzymes.

Fungal fibrinolytic enzymes, secreted by some Agaricomycetes, are recognized as important thrombolytic agents due to their ability to rapidly dissolve thromboembolic clots. The present work evaluated fibrinolytic and proteolytic secretion abilities of 35 Agaricomycetes isolates from the Paranaense rainforest (Misiones, Argentina). We detected proteolytic activity in 40% of the strains while nine strains showed fibrinolytic activity. Schizophyllum commune LBM 026, Schizophyllum commune LBM 223, and Hornodermoporus martius LBM 224 exhibited the highest levels of fibrinolytic activity. Fibrin zymography from S. commune LBM 026 and LBM 223 showed an enzyme of 27.5 kDa, while H. martius LBM 224 presented an enzyme of 29 kDa. The evaluation of the enzymatic stability of culture supernatant of these strains revealed that the fibrinolytic activity was highly stable over a wide temperature and pH range. Long-term stability of fibrinolytic activity at physiological conditions evidenced that the strains had a half-life of at least 72 h. Fibrinolytic enzymes produced by S. commune LBM 026 and LBM 223 were inhibited in the presence of EDTA indicating that they are metalloproteases. This work reveals the potential of S. commune LBM 026, S. commune LBM 223, and H. martius LBM 224 as an unconventional source of thrombolytic agents.

Diversity and Phylogeny of Novel Cord-Forming Fungi from Borneo.

Cord-forming (CF) fungi are found worldwide; however, tropical CF fungi are poorly documented. They play an essential role in forest ecosystems by interconnecting nutrient resources and aiding in the decomposition of plant matter and woody litter. CF fungi samples were collected from two forest conservation sites in the Sabah region of Malaysian Borneo. Sequencing and phylogenetic analysis of the ribosomal rRNA gene array 18S to 28S region from cords collected placed all of the collected specimens in Agaricomycetes (Basidiomycetes), specifically within the orders Trechisporales, Phallales, Hymenochaetales, Polyporales, and Agaricales. Comparison of the cord-derived sequences against GenBank and UNITE sequence databases, as well as phylogenetic analyses, revealed they were all novel sequences types. Many of these novel lineages were found to be closely related to other basidiomycetes commonly found in tropical forests, suggesting a large undiscovered tropical fungal diversity in Borneo that has been detected independently of sampling fruiting bodies. We show how these sequence types relate to the morphologies of the cords from which they were sampled. We also highlight how rapid, small-scale sampling can be a useful tool as an easy and relatively unbiased way of collecting data on cord-forming fungi in difficult-to-access, complex forest environments, independently of locating and sampling sporophores.

Redelimitation of Heteroradulum (Auriculariales, Basidiomycota) with H.australiense sp. nov.

Auriculariales accommodates species with diverse basidiomes and hymenophores. From morphological and phylogenetic perspectives, we perform a taxonomic study on Heteroradulum, a recently validated genus within the Auriculariales. The genus Grammatus is merged into Heteroradulum, and thus its generic type G.labyrinthinus is combined with Heteroradulum and G.semis is reaccepted as a member of Heteroradulum. Heteroradulumaustraliense is newly described on the basis of three Australian specimens. Heteroradulumyunnanense is excluded from this genus and its taxonomic position at the generic level is considered uncertain. Accordingly, the circumscription of Heteroradulum is re-delimited and the concept of this genus is adjusted by including irpicoid to poroid hymenophores and a hyphal system with clamp connections or simple septa. A key to all nine accepted species of Heteroradulum is presented.

Organic Nitrogen Supplementation Increases Vegetative and Reproductive Biomass in a Versatile White Rot Fungus.

The Black Poplar Mushroom Cyclocybe aegerita (syn. Agrocybe aegerita) is a white-rot fungus that naturally fruits from woody substrates, including buried wood. It is known for its substrate versatility and is equipped with a respective carbohydrate-active enzyme repertoire being intermediate between typical white-rot fungi and plant litter decomposers. Given relative nitrogen scarcity in wood, mobilization of nitrogen from surrounding litter is known as a way to meet nitrogen requirements for cellular homeostasis and reproduction of wood decay fungi. However, the effect of added nitrogen on vegetative and reproductive biomass has not yet been studied in a uniform minimalistic laboratory setup. For C. aegerita, such a growth and fruiting setup has been developed. In the present study, this white-rot fungus has been grown with and without additional ß-adenosine, an organic nitrogen source present in plant litter. Elevated ß-adenosine levels increased aerial mycelium weight by 30% (1 × ß-adenosine) and 55% (10 × ß-adenosine), reproductive biomass by 75% (1 × ß-adenosine) and by 100% (10 × ß-adenosine), number of primordia by 127% (10 × ß-adenosine) and accelerated primordium formation by 1.6 days (10 × ß-adenosine), compared to the control treatment. These findings imply that C. aegerita invests additional organic nitrogen resources into direct vegetative and reproductive biomass build-up at the same time. Colonization of niches with accessory nitrogen sources, like buried wood, which is near the plant litter layer, may thus provide an evolutionary fitness advantage. Globally anthropogenically altered nitrogen dynamics may affect hyphal-driven processes as well as fruit body-driven food webs.

Morphological Characteristics and Molecular Evidence Reveal four New Species of Russula subg. Brevipedum from China.

In this study, four new species of Russula subg. Brevipedum collected from China are described based on morphological characteristics and molecular evidence. Russula brevispora has a white body whose whole parts often stain brownish-orange or grayish-orange, extremely crowded lamellae with the presence of lamellulae, basidiospores with low warts and an inamyloid suprahilar spot, and clavate or lageniform hymenial cystidia often with a papillary or submoniliform appendage. Russula flavescens is characterized by a white pileus often turning yellowish brown when touched, white lamellae turning brown or light orange, basidiospores with an inamyloid suprahilar spot, and fusiform hymenial cystidia often with an appendage. Russula longicollis is morphologically characterized by a white pileus, turning grayish orange when bruised, white lamellae turning pale yellow when bruised, basidiospores with isolated warts and an amyloid suprahilar spot, and fusiform hymenial cystidia usually with a long appendage. Russula pseudojaponica has a yellowish-brown pileus center, yellowish lamellae unchanging when bruised, basidiospores with low warts and an inamyloid suprahilar spot, clavate hymenial cystidia often with a papillary appendage, and clavate pileocystidia with granulose contents. Phylogenetic analyses showed that R. flavescens, R. brevispora, and R. pseudojaponica are members of the subsect. Pallidosporinae, whereas R. longicollis belongs to subsect. Lactarioideae, and is somewhat related to R. leucocarpa.