Fungal diversity notes 111–252—taxonomic and phylogenetic contributions to fungal taxa

Four New Species and a New Combination of Boletaceae (Boletales) from Subtropical and Tropical China

Previous studies have shown that boletes are abundant and diverse in China, especially in tropical and subtropical regions. In the present study, morphological, ecological, host relationship, and a four-locus (28S, tef1, rpb1, and rpb2) molecular phylogenetic analyses were used to study the family Boletaceae in subtropical and tropical China. Four new bluing species are described from three genera, viz. Boletellus verruculosus (Chinese name), Xerocomellus tenuis (Chinese name), Xer. brunneus (Chinese name), and Xerocomus zhangii (Chinese name). Moreover, the genus Nigroboletus is treated as a synonym of Xerocomellus, and a new combination, namely Xer. roseonigrescens (Chinese name), is proposed.

New Insights into Tetraplosphaeriaceae Based on Taxonomic Investigations of Bambusicolous Fungi and Freshwater Fungi

Species within Tetraplosphaeriaceae have been frequently documented in recent years with the extensive investigations of microfungi along a latitudinal gradient from north to south in the Asian/Australian region. Both bamboo substrates and freshwater habitats serve as extensive reservoirs, hosting a rich diversity of fungi that exhibit broad geographical distributions. The most common fungi in these two environments are generally distributed in distinct families. However, our statistics have revealed an intriguingly distinct preference of Tetraplosphaeriaceae species for inhabiting both bamboo substrates and freshwater habitats. The genera Pseudotetraploa (100%) and Triplosphaeria (100%) exhibit a strong preference, followed by Shrungabeeja (71%) and Quadricrura (67%). Our taxonomic and phylogenetic study of microfungi in southern China have identified four additional novel species, viz., Aquatisphaeria bambusae sp. nov., Pseudotetraploa phyllostachydis sp. nov., Pseudotetraploa yangjiangensis sp. nov., and Tetraploa submersa sp. nov. from bamboo substrates and freshwater habitats. In addition, Aquatisphaeria thailandica has previously been documented from freshwater habitats in Thailand; however, we have once again isolated this species from decaying bamboo substrates in Guangdong, China. The new findings substantiate our hypothesis that the preference of Tetraplosphaeriaceae species for colonizing bamboo substrates and freshwater habitats will be more evident through more extensive investigations conducted in such environments.

Agaricus subgenus Pseudochitonia in Malakand, Pakistan: An updated phylogeny and description of three new species

Agaricus is a genus with more than 500 species. Most of the new species reported since 2000 are tropical or subtropical. The study area, the Malakand region, located in the north of Pakistan, has a subtropical climate. In this study, nine species, including three new species, of Agaricus subgenus Pseudochitonia, are reported from this region. Description of the new species are based on morphological characteristics and phylogenetic analyses using three DNA regions: nuc ribosomal DNA internal transcribed spacers (ITS), fragments of the large subunit of nuc ribosomal DNA (28S), and the translation elongation factor 1-alpha gene (TEF1). One new species, Agaricus lanosus, with wooly squamules on its cap, forms a lineage within Agaricus sect. Bivelares and cannot be classified with certainty in one of the two subsections (Cupressorum and Hortenses) of this section. Agaricus rhizoideus with rhizoid-like structure at the base of the stipe forms a basal clade in Agaricus sect. Hondenses. Specimens of the third new species, Agaricus malakandensis, form a species-level clade within Agaricus sect. Catenulati and exhibits the morphological characteristics of this section. Due to their similar ITS sequences, two previously unnamed specimens from Thailand (A. sp. LD2012162 and CA799) are considered conspecific with A. malakandensis.

Three new species of Cortinarius section Delibuti (Cortinariaceae, Agaricales) from China

Three new species of CortinariussectionDelibuti, namely C.fibrillososalor, C.pseudosalor, and C.subtropicus are described as new to science based on morphological and phylogenetic evidences. Cortinariuspseudosalor is extremely morphologically similar to C.salor, but it differs from the latter by smaller coarsely verrucose basidiospores. Cortinariusfibrillososalor can be easily differentiated by its fibrillose pileus. The pileus of C.subtropicus becomes brown without lilac tint at maturity comparing with other members of section Delibuti. A combined dataset of ITS and LSU sequences was used for phylogenetic analysis. The phylogenetic reconstruction of section Delibuti revealed that these three new species clustered and formed independent lineages with full support respectively. A key to the three new species and related species of section Delibuti is provided in this work.

Umbellaceae fam. nov. (Hymenochaetales, Basidiomycota) for Umbellus sinensis gen. et sp. nov. and Three New Combinations

Hymenochaetales, belonging to Agaricomycetes, Basidiomycota, comprises most polypores and corticioid fungi and, also, a few agarics. The latest taxonomic framework accepts 14 families in this order. When further exploring species diversity of Hymenochaetales, two corticioid specimens collected from China producing cystidia with large umbrella-shaped crystalline heads attracted our attention. This kind of cystidia was reported only in three unsequenced species, viz. Tubulicrinis corneri, T. hamatus and T. umbraculus, which were accepted in Tubulicrinaceae, Hymenochaetales. The current multilocus-based phylogeny supports that the two Chinese specimens formed an independent lineage from Tubulicrinaceae as well as the additional 13 families and all sampled genera in Hymenochaetales. Therefore, a monotypic family, Umbellaceae, is newly described with the new genus Umbellus as the type genus to represent this lineage. The two Chinese specimens are newly described as U. sinensis, which differs from T. corneri, T. hamatus, and T. umbraculus in a combination of a smooth to grandinioid hymenophoral surface, not flattened, broadly ellipsoid basidiospores with a tiny apiculus, and growth on angiosperm wood. Due to the presence of the unique cystidia, the three species of Tubulicrinis, even though they lack available molecular sequences, are transferred to Umbellus as U. corneri, U. hamatus, and U. umbraculus. Hereafter, all known species with large umbrella-shaped crystalline-headed cystidia are in a single genus. In summary, the current study provides a supplement to the latest taxonomic framework of Hymenochaetales and will help to further explore species diversity and the evolution of this fungal order.

Morphophylogenetic evidence reveals four new fungal species within Tetraplosphaeriaceae (Pleosporales, Ascomycota) from tropical and subtropical forest in China

Tetraplosphaeriaceae (Pleosporales, Ascomycota) is a family with many saprobes recorded from various hosts, especially bamboo and grasses. During a taxonomic investigation of microfungi in tropical and subtropical forest regions of Guizhou, Hainan and Yunnan provinces, China, several plant samples were collected and examined for fungi. Four newly discovered species are described based on morphology and evolutionary relationships with their allies inferred from phylogenetic analyses derived from a combined dataset of LSU, ITS, SSU, and tub2 DNA sequence data. Detailed illustrations, descriptions and taxonomic notes are provided for each species. The four new species of Tetraplosphaeriaceae reported herein are Polyplosphaeriaguizhouensis, Polyplosphaeriahainanensis, Pseudotetraploayunnanensis, and Tetraploahainanensis. A checklist of Tetraplosphaeriaceae species with available details on their ecology is also provided.

Taxonomic and phylogenetic characterisations of six species of Pleosporales (in Didymosphaeriaceae, Roussoellaceae and Nigrogranaceae) from China

Pleosporales comprise a diverse group of fungi with a global distribution and significant ecological importance. A survey on Pleosporales (in Didymosphaeriaceae, Roussoellaceae and Nigrogranaceae) in Guizhou Province, China, was conducted. Specimens were identified, based on morphological characteristics and phylogenetic analyses using a dataset composed of ITS, LSU, SSU, tef1 and rpb2 loci. Maximum Likelihood (ML) and Bayesian analyses were performed. As a result, three new species (Neokalmusiakarka, Nigrogranaschinifolium and N.trachycarpus) have been discovered, along with two new records for China (Roussoellaneopustulans and R.doimaesalongensis) and a known species (Roussoellapseudohysterioides). Morphologically similar species and phylogenetically close taxa are compared and discussed. This study provides detailed information and descriptions of all newly-identified taxa.

Palm Fungi and Their Key Role in Biodiversity Surveys: A Review

Over the past three decades, a wealth of studies has shown that palm trees (Arecaceae) are a diverse habitat with intense fungal colonisation, making them an important substratum to explore fungal diversity. Palm trees are perennial, monocotyledonous plants mainly restricted to the tropics that include economically important crops and highly valued ornamental plants worldwide. The extensive research conducted in Southeast Asia and Australasia indicates that palm fungi are undoubtedly a taxonomically diverse assemblage from which a remarkable number of new species is continuously being reported. Despite this wealth of data, no recent comprehensive review on palm fungi exists to date. In this regard, we present here a historical account and discussion of the research on the palm fungi to reflect on their importance as a diverse and understudied assemblage. The taxonomic structure of palm fungi is also outlined, along with comments on the need for further studies to place them within modern DNA sequence-based classifications. Palm trees can be considered model plants for studying fungal biodiversity and, therefore, the key role of palm fungi in biodiversity surveys is discussed. The close association and intrinsic relationship between palm hosts and palm fungi, coupled with a high fungal diversity, suggest that the diversity of palm fungi is still far from being fully understood. The figures suggested in the literature for the diversity of palm fungi have been revisited and updated here. As a result, it is estimated that there are about 76,000 species of palm fungi worldwide, of which more than 2500 are currently known. This review emphasises that research on palm fungi may provide answers to a number of current fungal biodiversity challenges.

Taxonomy and evolution history of two new litter-decomposing Ciliochorella (Amphisphaeriales, Sporocadaceae)

The genus Ciliochorella is a group of pestalotioid fungi, which typically occurs in subtropical and tropical areas. Species from the Ciliochorella genus play important roles in the decomposition of litter. In this study, we introduce two new species (Ciliochorellachinensissp. nov. and C.savannicasp. nov.) that were found on leaf litter collected from savanna-like vegetation in hot dry valleys of southwestern China. Phylogenetic analyses of combined LSU, ITS and tub2 sequence datasets indicated that C.chinensis and C.savannica respectively form a distinct clade within the Ciliochorella genus. The comparison of the morphological characteristics indicated that the two new species are well differentiated within this genus species. Analysis of the evolutionary history suggests that Ciliochorella originated from the Eurasian continent during the Paleogene (38 Mya). Further, we find that both new species can produce cellulase and laccase, playing a decomposer role.

A phylogeny for North American Mallocybe (Inocybaceae) and taxonomic revision of eastern North American taxa

A multigene phylogenetic assessment of North American species of Mallocybe is presented based on analyses of rpb1, rpb2, ITS, and 28S rDNA nucleotide data. This framework enables a systematic revision of the genus for 16 eastern North American species and captures taxonomic and phylogenetic diversity in a global context. A grade of two unusual and poorly known North American species stems from the most recent common ancestor of the genus that gives rise to three core subgroups named here as clades Unicolores, Nothosperma, and Mallocybe. The grade of taxa includes the poorly known Lepista praevillosa from Florida and a new species from the southern Appalachians, M. montana, both of which appear to be narrow-range endemics. Clade Nothosperma is characterized by Australian and New Zealand species, whereas clade Unicolores is composed of six species from eastern North America and East Asia. Clade Mallocybe is dominated by numerous north temperate taxa and constitutes the sister group to clade Nothosperma. These major clades are distinguished by a combination of phylogeny, morphology, geographic distribution, and ecology. In addition, four North American species are described as new: M. leucothrix, M. luteobasis, M. montana, and M. tomentella. Several names originating in North America, long ignored or misunderstood in the literature, are revitalized and established by type comparisons and modern reference material collected from or near type localities. In addition, 11 species were subjected to mass spectrometry muscarine assays, none of which contained detectable amounts of muscarine except for two: M. sabulosa and M. praevillosa. This confirms a diffuse phylogenetic distribution of muscarine within the genus. Taxonomic descriptions are presented for 16 species, several synonymies proposed, and four new combinations made. A key to species of eastern North American Mallocybe is presented, along with illustrations of important diagnostic features. Citation: Matheny PB, Kudzma LV, Graddy MG, Mardini SM, Noffsinger CR, Swenie RA, Walker NC, Campagna SR, Halling R, Lebeuf R, Kuo M, Lewis DP, Smith ME, Tabassum M, Trudell SA, Vauras J (2023). A phylogeny for North American Mallocybe (Inocybaceae) and taxonomic revision of eastern North American taxa. Fungal Systematics and Evolution 12: 153-201. doi: 10.3114/fuse.2023.12.09.

Diversity and taxonomy of the genus Amanita (Amanitaceae, Agaricales) in the Yanshan Mountains, Northern China

Globally, the species of Amanita are key components of ectomycorrhizal ecosystems. Some of them are widely known as poisonous or edible fungi. Although many new Amanita species from China have been described, the species diversity of Yanshan Mountains remains unknown. We here describe three new species, namely, A. borealis sp. nov. (Sect. Amanita), A. brunneola sp. nov. (Sect. Caesareae), and A. yanshanensis sp. nov. (Sect. Validae), based on morphological observations and molecular phylogenetic analyses. In addition, nine known species, namely, A. caesareoides (Sect. Caesareae), A. chiui (Sect. Vaginatae), A. muscaria (Sect. Amanita), A. oberwinklerana (Sect. Roanokenses), A. ovalispora (Sect. Vaginatae), A. subglobosa (Sect. Amanita), A. subjunquillea (Sect. phalloideae), A. vaginata var. vaginata (Sect. Vaginatae), and A. virosa (Sect. phalloideae), were reported from Yanshan Mountains for the first time. Our results emphasize that China has a high diversity of Amanita species and that additional studies are required to understand the exact species number. These findings play a crucial role in Amanita toxin research and ecological conservation. This study investigated the areas where Amanita species-related research is lacking. The study also attempted to better understand Amanita distribution and thus contribute to related research. This study enriches the species diversity of Amanita in Yanshan Mountains and offers additional data supporting the macrofungal systematics, toxin research, and diversity and ecological studies of Amanita in future studies.

Diversity and functional prediction of fungal communities in different segments of mongolian horse gastrointestinal tracts

BACKGROUND

Anaerobic fungi are effective fibre-degrading microorganisms in the digestive tract of horses. However, our understanding of their diversity and community structure is limited, especially in different parts of the gastrointestinal tract.

RESULTS

For the first time, high-throughput sequencing technology was used to analyse and predict fungal microbial diversity in different parts of the gastrointestinal tract of Mongolian horses. The results revealed that the richness and diversity of fungi in the hindgut of Mongolian horses were much higher than those in the foregut. The foregut was dominated by Basidiomycota and Ascomycota, whereas the hindgut was dominated by Neocallimastigomycota and Basidiomycota. At the genus level, the relative abundance of many pathogenic fungi (Cryptococcus, Cladosporium, Alternaria, and Sarocladium) in the foregut was significantly higher than that in the posterior gut, indicating that Mongolian horses have strong disease resistance. The prediction of fungal function also showed significant differences in the fungal flora between the foregut and the hindgut. The fungi in Mongolian horses' foreguts were mainly pathologically nutritive and contained many animal and plant pathogens, particularly in the small intestine (jejunum and ileum). This indicates that the foregut may be the most important immune site in the digestive system of Mongolian horses, which explains the high disease resistance of Mongolian horses. The number of unassigned functional groups in the posterior gut was significantly higher than that in the anterior gut, indicating that the functions of fungal groups in the posterior gut have not been fully explored, and further studies are required in the future.

CONCLUSIONS

Analysis of high-throughput sequencing results revealed that the fungal composition varied greatly among different gastrointestinal tract segments in Mongolian horses, whose hindgut contains many anaerobic fungi involved in plant cellulose degradation. This provides important basic data for studying fungal diversity in the digestive system of healthy horses, which can be used for the health assessment of horses and provides clues for further research on the disease resistance and digestive capacity of horses, as well as a reference for the early diagnosis of intestinal diseases and innovative treatment methods.

New species of Mallocybe (Agaricales, Inocybaceae) from Pakistan, based on morphological and molecular evidence

Within the family Inocybaceae, many species of Mallocybe have been reported, but there are only a few reports of this genus from Pakistan. In this study, six collections of Mallocybe were studied by morphological and phylogenetic methods. Phylogenetic analyses, based on sequence data from two different loci (ITS and LSU) using Maximum Likelihood and Maximum Parsimony methods, have been performed to infer species relationships within Mallocybe. Results indicated that these six collections encompass two new species of Mallocybe i.e. M.pakistanica and M.pinicola, from Pakistan. Their detailed morphological descriptions and illustrations are also provided. In addition, comparison with morphologically closely-related taxa is also discussed. Previously, only two species of this genus have been recorded from Pakistan and, with this addition, the total number of reported taxa of Mallocybe has been raised to four from Pakistan. A key to the described taxa of Mallocybe from Pakistan is also provided.

Isolates of Colletotrichum truncatum with Resistance to Multiple Fungicides from Soybean in Northern Thailand

In Thailand, four systemic fungicides-carbendazim (Car), azoxystrobin (Azo), difenoconazole (Dif), and penthiopyrad (Pen)-are commonly used to control soybean anthracnose caused by Colletotrichum truncatum; however, the pathogen has developed resistance. From 2019 to 2020, fungicide resistance in C. truncatum from fields in Chiang Rai and Chiang Mai was monitored. In tests of 85 C. truncatum isolates for resistance to multiple fungicides, 15.3% were CarRAzoR, 34.1% were triple resistant (CarRAzoRDifR or CarRAzoRPenR), and 50.6% were CarRAzoRDifRPenR. Surprisingly, all isolates tested had lost their sensitivity to one or more of the fungicides tested. The carbendazim-resistant isolates carried a point mutation in the β-tubulin gene at codon 198 (E198A) or 200 (F200Y), and all azoxystrobin-resistant isolates had a mutation in the cytochrome b gene at codon 143 (G143A) or 129 (F129L). Moreover, a novel mutation at codon 208 (S208Y) in the gene encoding succinate dehydrogenase subunit B was detected in all of the isolates highly resistant to penthiopyrad. No mutation linked with difenoconazole resistance was detected in the genes encoding cytochrome P450 sterol 14α-demethylase. To the best of our knowledge, this is the first report of C. truncatum isolates resistant to multiple fungicides and serves as a warning to take measures to prevent the occurrence and distribution of these multiple-fungicide-resistant populations in soybean fields.

Species Diversity of Amanita Section Vaginatae in Eastern China, with a Description of Four New Species

Species of Amanita sect. Vaginatae (Fr.) Quél. are challenging to delimitate due to the morphological similarity or morphostasis among different taxa. In this study, a multi-locus (nuc rDNA region encompassing the internal transcribed spacers 1 and 2 with the 5.8S rDNA, the D1-D3 domains of nuc 28S rDNA, partial sequences of translation elongation factor 1-a, and the second largest subunit of RNA polymerase II) phylogeny was employed to investigate the species diversity of the section in eastern China. Sixteen species were recognized, including four new species; namely, A. circulata, A. multicingulata, A. orientalis, and A. sinofulva. They were documented with illustrated descriptions, ecological evidence, and comparisons with similar species. A key to the species of the section from eastern China is provided.

Exploring the Diversity and Systematics of Phaeosphaeriaceae: Taxonomic Novelties from Ecologically Diverse Habitats and Their Phylogenetic Resolution

The family Phaeosphaeriaceae is a diverse group of ascomycetous fungi that are commonly found in terrestrial habitats worldwide. In recent years, there has been increasing interest in the biodiversity of Phaeosphaeriaceae in China, particularly in Sichuan Province, which has not been fully explored for its high fungal diversity. In our study, we conducted extensive surveys in Sichuan Province to identify and describe new species of Ascomycota with diverse habitats. Here, we present a taxonomic revision of Phaeosphaeriaceae with taxonomic novelties from terrestrial habitats in Sichuan Province based on a multi-gene phylogenetic approach. Our study focuses on the description of four new species of Phaeosphaeriaceae, representing novel additions to the diversity of this fungal family. Using a combination of morphological and molecular data, we provide detailed descriptions of the new taxa and their placement within the family. Additionally, we discuss the phylogenetic relationships of these new taxa with other members of Phaeosphaeriaceae, providing insights into the correct taxonomic classification of the family. Our taxonomic revision contributes to understanding fungal diversity in China and provides a foundation for future studies investigating the taxonomy and ecological roles of Phaeosphaeriaceae fungi. Furthermore, our multi-gene phylogenetic approach provides increased resolution and accuracy in the delimitation of species boundaries within the family. Our study highlights the importance of continued exploration and taxonomic revision in order to fully understand the diversity and distribution of fungal species in China and beyond. New species:Paraloratospora sichuanensis, Phaeosphaeria chengduensis, P. sichuanensis, and Septoriella shoemakeri. New combinations:Paraloratospora breonadiae, P. fructigena, Septoriella ammophilicola, S. asparagicola, S. festucae, S. luzulae, and S. verrucispora. New names:Septoriella paradactylidis, and S. neomuriformis.

Four new additions to Helvella (Helvellaceae, Pezizales) from Northern Thailand

Most species of Helvella have been described from temperate regions in Asia, Europe, and North America, but little is known about the genus from tropical regions. In this report, phylogenetic analyses of 11 newly collected saddle-like fungi from northern Thailand using three genetic markers [the nuclear large subunit ribosomal DNA (LSU), the heat shock protein 90 (HSP90), and the translation elongation factor 1-alpha (TEF)] confirm their assignment in Helvella. Two species were described as new, i.e., Helvella atroides and H. orentitomentosa, and two species, i.e., H. fistulosa and H. rugosa, were reported for the first time in Thailand. Details of macro- and microscopic characters and illustrations were provided for each species. To date, seven species of Helvella have been recorded in Thailand, and a key for identifying the Thai Helvella species was provided here.

Species Diversity of Helvella lacunosa Clade (Pezizales, Ascomycota) in China and Description of Sixteen New Species

Helvella lacunosa and its allies are widely distributed in the Northern Hemisphere and perform important functions in ecosystems. A comprehensive study on 101 collections of Helvella lacunosa, including those deposited in four Chinese fungaria or collected recently from 10 provinces, was conducted based on morphological and molecular characteristics. Phylogenies of "Helvella lacunosa clade" inferred from Hsp90, ITS, LSU, and TEF were reconstructed with 49 lineages recognized, of which 25 lineages occurred in China, and each represented an individual species. Sixteen new species were determined with detailed descriptions and illustrations. Two new Chinese records were reported. Species concepts and their distinctions in macro- and micro-features were discussed.

Enhanced mercury phytoremediation by Pseudomonodictys pantanalensis sp. nov. A73 and Westerdykella aquatica P71

Mercury is a non-essential and toxic metal that induces toxicity in most organisms, but endophytic fungi can develop survival strategies to tolerate and respond to metal contaminants and other environmental stressors. The present study demonstrated the potential of mercury-resistant endophytic fungi in phytoremediation. We examined the functional traits involved in plant growth promotion, phytotoxicity mitigation, and mercury phytoremediation in seven fungi strains. The endophytic isolates synthesized the phytohormone indole-3-acetic acid, secreted siderophores, and solubilized phosphate in vitro. Inoculation of maize (Zea mays) plants with endophytes increased plant growth attributes by up to 76.25%. The endophytic fungi stimulated mercury uptake from the substrate and promoted its accumulation in plant tissues (t test, p < 0.05), preferentially in the roots, which thereby mitigated the impacts of metal phytotoxicity. Westerdykella aquatica P71 and the newly identified species Pseudomonodictys pantanalensis nov. A73 were the isolates that presented the best phytoremediation potential. Assembling and annotation of P. pantanalensis A73 and W. aquatica P71 genomes resulted in genome sizes of 45.7 and 31.8 Mb that encoded 17,774 and 11,240 protein-coding genes, respectively. Some clusters of genes detected were involved in the synthesis of secondary metabolites such as dimethylcoprogen (NRPS) and melanin (T1PKS), which are metal chelators with antioxidant activity; mercury resistance (merA and merR1); oxidative stress (PRX1 and TRX1); and plant growth promotion (trpS and iscU). Therefore, both fungi species are potential tools for the bioremediation of mercury-contaminated soils due to their ability to reduce phytotoxicity and assist phytoremediation.

Taxonomy and Phylogeny of Hyphomycetous Muriform Conidial Taxa from the Tibetan Plateau, China

During the investigation of lignicolous freshwater fungi in the Tibetan Plateau habitat, fifteen collections were isolated from submerged decaying wood. Fungal characteristics are commonly found as punctiform or powdery colonies with dark pigmented and muriform conidia. Multigene phylogenetic analyses of combined ITS, LSU, SSU and TEF DNA sequences showed that they belong to three families in Pleosporales. Among them, Paramonodictys dispersa, Pleopunctum megalosporum, Pl. multicellularum and Pl. rotundatum are established as new species. Paradictyoarthrinium hydei, Pleopunctum ellipsoideum and Pl. pseudoellipsoideum are reported as new records on the freshwater habitats in Tibetan Plateau, China. The morphological descriptions and illustrations of the new collections are provided.

Polydomus karssenii gen. nov. sp. nov. is a dark septate endophyte with a bifunctional lifestyle parasitising eggs of plant parasitic cyst nematodes (Heterodera spp.)

In this study fungal strains were investigated, which had been isolated from eggs of the cereal cyst nematode Heterodera filipjevi, and roots of Microthlaspi perfoliatum (Brassicaceae). The morphology, the interaction with nematodes and plants and the phylogenetic relationships of these strains originating from a broad geographic range covering Western Europe to Asia Minor were studied. Phylogenetic analyses using five genomic loci including ITSrDNA, LSUrDNA, SSUrDNA, rpb2 and tef1-α were carried out. The strains were found to represent a distinct phylogenetic lineage most closely related to Equiseticola and Ophiosphaerella, and Polydomus karssenii (Phaeosphaeriaceae, Pleosporales) is introduced here as a new species representing a monotypic genus. The pathogenicity tests against nematode eggs fulfilled Koch's postulates using in vitro nematode bioassays and showed that the fungus could parasitise its original nematode host H. filipjevi as well as the sugar beet cyst nematode H. schachtii, and colonise cysts and eggs of its hosts by forming highly melanised moniliform hyphae. Light microscopic observations on fungus-root interactions in an axenic system revealed the capacity of the same fungal strain to colonise the roots of wheat and produce melanised hyphae and microsclerotia-like structure typical for dark septate endophytes. Confocal laser scanning microscopy further demonstrated that the fungus colonised the root cells by predominant intercellular growth of hyphae, and frequent formation of appressorium-like as well as penetration peg-like structures through internal cell walls surrounded by callosic papilla-like structures. Different strains of the new fungus produced a nearly identical set of secondary metabolites with various biological activities including nematicidal effects irrespective of their origin from plants or nematodes.

Pestalotioid Species Associated with Medicinal Plants in Southwest China and Thailand

In this paper, a total of 26 pestalotioid isolates associated with different medicinal plants from southwest China and Thailand were studied. Based on morphological examinations and multigene analyses of three gene loci (ITS, tef1-α, and tub2), these 26 isolates represent 17 species distributed in three genera, including seven new species and eight new records. The concatenated three loci tree was used to infer the occurrence of sexual recombination within each pestalotioid genus through the pairwise homoplasy index (PHI) test implemented in SplitsTree. Further, simplifying the description of pestalotioid species is discussed, and a checklist for pestalotioid species associated with medicinal plants worldwide is provided. IMPORTANCE Pestalotioid species are an important fungal group, occurring commonly as plant pathogens, endophytes, and saprophytes. The study of pestalotioid species associated with medicinal plants is significant for agriculture, industry, and pharmaceutical industry but remains poorly studied. In this study, we report 17 pestalotioid species related to medicinal plants based on morphology and molecular analyses. Our study significantly enriches the species richness of pestalotioids and provides a basis for follow-up studies.

Multiverruca sinensis gen. nov., sp. nov., a thermotolerant fungus isolated from soil in China

During a survey of thermotolerant fungi in China, three isolates were obtained from soil samples. Phylogenetic analysis of a combined internal transcribed spacer and large subunit dataset showed that these isolates belong to the same species, which form a well-separated lineage distinct from the other genera in Latoruaceae. Morphologically, the isolates are characterized by having globose and smooth conidiogenous cells, verruculose mycelium and cymbiform conidia. Combining the phylogenetic analyses and morphological characteristics, Multiverruca gen. nov. is proposed and introduced to accommodate a single new species, Multiverruca sinensis sp. nov. Detailed descriptions, illustrations and notes are provided for the new genus and species.

Plant-Associated Novel Didymellaceous Taxa in the South China Botanical Garden (Guangzhou, China)

The South China Botanical Garden (SCBG), one of the largest and oldest botanical gardens in China, conserves important plant germplasms of endangered species. Therefore, ensuring tree health and studying the associated mycobiome of the phyllosphere is essential to maintaining its visual aesthetics. During a survey of plant-associated microfungal species in SCBG, we collected several coelomycetous taxa. Phylogenetic relationships were evaluated based on the analyses of ITS, LSU, RPB2, and β-tubulin loci. The morphological features of the new collections were compared with those of existing species, emphasizing close phylogenetic affinities. Based on the morphological comparisons and multi-locus phylogeny, we introduce three new species. These are Ectophoma phoenicis sp. nov., Remotididymella fici-microcarpae sp. nov., and Stagonosporopsis pedicularis-striatae sp. nov. In addition, we describe a new host record for Allophoma tropica in the Didymellaceae. Detailed descriptions and illustrations are provided along with notes comparing allied species.

Re-Evaluating Botryosphaeriales: Ancestral State Reconstructions of Selected Characters and Evolution of Nutritional Modes

Botryosphaeriales (Dothideomycetes, Ascomycota) occur in a wide range of habitats as endophytes, saprobes, and pathogens. The order Botryosphaeriales has not been subjected to evaluation since 2019 by Phillips and co-authors using phylogenetic and evolutionary analyses. Subsequently, many studies introduced novel taxa into the order and revised several families separately. In addition, no ancestral character studies have been conducted for this order. Therefore, in this study, we re-evaluated the character evolution and taxonomic placements of Botryosphaeriales species based on ancestral character evolution, divergence time estimation, and phylogenetic relationships, including all the novel taxa that have been introduced so far. Maximum likelihood, maximum parsimony, and Bayesian inference analyses were conducted on a combined LSU and ITS sequence alignment. Ancestral state reconstruction was carried out for conidial colour, septation, and nutritional mode. Divergence times estimates revealed that Botryosphaeriales originated around 109 Mya in the early epoch of the Cretaceous period. All six families in Botryosphaeriales evolved in the late epoch of the Cretaceous period (66-100 Mya), during which Angiosperms also appeared, rapidly diversified and became dominant on land. Families of Botryosphaeriales diversified during the Paleogene and Neogene periods in the Cenozoic era. The order comprises the families Aplosporellaceae, Botryosphaeriaceae, Melanopsaceae, Phyllostictaceae, Planistromellaceae and Saccharataceae. Furthermore, current study assessed two hypotheses; the first one being "All Botryosphaeriales species originated as endophytes and then switched into saprobes when their hosts died or into pathogens when their hosts were under stress"; the second hypothesis states that "There is a link between the conidial colour and nutritional mode in botryosphaerialean taxa". Ancestral state reconstruction and nutritional mode analyses revealed a pathogenic/saprobic nutritional mode as the ancestral character. However, we could not provide strong evidence for the first hypothesis mainly due to the significantly low number of studies reporting the endophytic botryosphaerialean taxa. Results also showed that hyaline and aseptate conidia were ancestral characters in Botryosphaeriales and supported the relationship between conidial pigmentation and the pathogenicity of Botryosphaeriales species.

Morphological Characteristics and Phylogeny Reveal Six New Species in Russula Subgenus Russula (Russulaceae, Russulales) from Yanshan Mountains, North China

Species of the genus Russula are key components of ectomycorrhizal ecosystems worldwide, some of which are famous edible fungi. Although many new species have been described in China, their diversity in North China is still poorly known. Based on the morphology observation of specimens and molecular phylogenetic analyses, combined with the current classification frame of Russula, six new species of Russula subgenus Russula are proposed from the Yanshan Mountains in northern Beijing and northern Hebei Province of China in this study: viz. Russula miyunensis (subsection Chamaeleontinae), R. plana (subsection Chamaeleontinae), R. sinoparva (subsection Puellarinae), R. sinorobusta (subsection Puellarinae), R. subversatilis (subsection Roseinae), and R. yanshanensis (subsection Puellarinae). This is the first report of the species of Russula subgenus Russula from the Yanshan Mountains. This study enriches the species diversity of Russula in North China and provides new data support for the systematic study of Russula in subsequent research, including research and development on edibility.

Taxonomic Novelties of Woody Litter Fungi (Didymosphaeriaceae, Pleosporales) from the Greater Mekong Subregion

The Greater Mekong Subregion (GMS) is known as a diverse geographic landscape and one of the richest biodiversity hotspots in the world with a high fungal diversity. Collections were carried out in terrestrial habitats to determine the diversity of woody litter fungi in the GMS, with an emphasis on northern Thailand and the Yunnan Province of China. Morphological characteristics and multigene phylogenetic analyses of combined SSU, LSU, ITS, and tef1-α supported the placement of the new isolates in the family Didymosphaeriaceae. The phylogenetic affinities of our isolates are illustrated through maximum likelihood and Bayesian inference analyses. Seven species of woody litter fungi were identified, comprising a new monotypic genus, Septofusispora; five novel species (Chromolaenicola sapindi, Dictyoarthrinium thailandicum, Karstenula lancangensis, Septofusispora thailandica, and Spegazzinia jinghaensis); and new host records of two species (Austropleospora archidendri, and Montagnula donacina). Furthermore, this study provides a synopsis of the Montagnula aff. donacina species based on their morphological characteristics, which can be useful in the species-level identifications in this genus.

New species and records of Neomassaria, Oxydothis and Roussoella (Pezizomycotina, Ascomycota) associated with palm and bamboo from China

Several micro fungi were gathered from bamboo and palm in Guizhou Province, China. In morphology, these taxa resemble Neomassaria, Roussoella and Oxydothis. Multi-gene phylogenetic analyses based on combined ITS, LSU, SSU, rpb2 and tef1 loci confirmed that two are new geographical records for China, (viz. Roussoellasiamensis, Neomassariafabacearum), while two of them are new to science (viz. Oxydothisfortunei sp. nov. and Roussoellabambusarum sp. nov.). The stromata of Roussoellabambusarum are similar to those of R.thailandica, but its ascospores are larger. In addition, multi-gene phylogenetic analyses show that Oxydothisfortunei is closely related to O.inaequalis, but the J- ascus subapical ring as well as the ascospores of O.inaequalis are smaller. Morphological descriptions and illustrations of all species are provided.

Multigene phylogeny, morphology, and pathogenicity trials reveal novel Cytospora species involved in perennial canker disease of apple trees in Iran

In recent years, canker and die-back diseases have become a growing threat for the productivity and longevity of apple orchards in Iran. In this study, 131 Cytospora isolates were recovered from symptomatic tissues of apple trees in apple orchards of Iran. Multigene phylogenetic inference based on combined sequence data of ITS, act, rpb2, and tef1-α loci, supplemented with morphological characteristics and pathogenicity assay revealed four novel Cytospora species which were described as C. avicennae, C. azerbaijanica, C. ershadii, and C. iranica, and four known species, namely C. chrysosperma, C. parasitica, C. paratranslucens, and C. sorbicola. Also, C. sorbicola is newly reported on apple trees worldwide. Koch's postulates were fulfilled to confirm that all eight species in this study were pathogenic on apple trees in Iran, among which C. sorbicola was the most intensive species. The results of this study further highlight rich diversity among Cytospora species occurring on apple trees, revealing several novel Cytospora species on this host. The host range, geographical distribution, and economic significance of novel species on apple industry remains to be studied.

Description of Four Novel Species in Pleosporales Associated with Coffee in Yunnan, China

In Yunnan Province, the coffee-growing regions are mainly distributed in Pu’er and Xishuangbanna. During the surveys of microfungi associated with coffee in Yunnan Province, seven taxa were isolated from coffee samples. Based on molecular phylogenetic analyses of combined ITS, LSU, SSU, rpb2, and tef1-α sequence data and morphological characteristics, four new species viz. Deniquelata yunnanensis, Paraconiothyrium yunnanensis, Pseudocoleophoma puerensis, and Pse. yunnanensis, and three new records viz. Austropleospora keteleeriae, Montagnula thailandica, and Xenocamarosporium acaciae in Pleosporales are introduced. In addition, Paracamarosporium fungicola was transferred back to Paraconiothyrium based on taxonomy and DNA sequences. Full descriptions, illustrations, and phylogenetic trees to show the placement of new and known taxa are provided. In addition, the morphological comparisons of new taxa with closely related taxa are given.

Note on the genus Nemania (Xylariaceae) - first records and a new species of the genus from Iran

In a survey of xylarialean fungi in northern Iran, some specimens attributable to the genus Nemania were collected, cultured and sequenced. Morphological evidence and phylogenetic analyses of a combined ITS, LSU, RPB2 and TUB2 gene dataset confirmed the presence of Nemaniadiffusa and N.serpens in Iran for the first time. Furthermore, the new species N.hyrcana, which shows similarities to N.subaenea and its putative synonym N.plumbea, but significantly differs from the latter in its DNA sequences, was encountered. All species are illustrated, described and discussed. In the phylogenetic analyses, for the first time, the overlooked ex-type ITS sequences of the neotype of the generic type, N.serpens and that of the holotype of N.prava, were added to a multi-gene matrix of Nemania. This revealed that the two accessions of N.serpens (HAST 235 and CBS 679.86), for which multigene data are available in GenBank, are misidentified, while the Iranian accession of N.serpens has an almost identical ITS sequence to the neotype, confirming its morphological species identification. The two previously accepted species of Euepixylon, E.udum and E.sphaeriostomum, are embedded within Nemania and are revealed as close relatives of N.serpens, supporting the inclusion of Euepixylon in Nemania.

Anamorphic chaetosphaeriaceous fungi from China

Chaetosphaeriaceae is one of the largest families in Sordariomycetes with its members commonly found on decaying leaf, fruit, branch, bark and wood in both terrestrial and submerged environment in nature. This paper reports our research result of diversity, taxonomy and phylogeny of anamorphic Chaetosphaeriaceae in China, which is based on a systematic study with an integrated approach of morphological observation and phylogenetic analysis for a large collection (> 1300 herbarium specimens and 1100 living strains). The family Chaetosphaeriaceae is expanded to accommodate 89 accepted genera, including 22 new genera and 10 newly assigned genera. Most of these genera (except for Chaetosphaeria and several other relatively large genera) are delimitated as monophyletic genera with well-defined diagnostic characters in morphology. The phylogenetic connection of non-phialidic Sporidesmium-like fungi is further confirmed and expanded to 10 different genera. The polyphyletic Codinaea/Dictyochaeta/Tainosphaeria complex is further resolved with a taxonomic framework of 28 monophyletic genera by redelimitation of Codinaea and Dictyochaeta with narrower concept, acceptance of the 16 established genera, and finally introduction of 10 new genera. Chloridium is phylogenetically redefined as monophyletic genus with narrower concept as typified by the type species, but a systematic review in both generic and species level is still needed. For biodiversity of chaetosphaeriaceous fungi, a total of 369 species in 76 genera, including 119 new species, 47 new combinations, and one new name, are documented. The identification keys are provided for most genera, especially the large genera such as Codinaea s. str., Codinaeella, Stilbochaeta, Cryptophiale, Thozetella, Dinemasporium and Pseudolachnella. In addition, ten known species were excluded from the family and reclassified. Systematic revision of several relatively large polyphyletic genera should be conducted in future studies, including Bahusutrabeeja, Ellisembia, Stanjehughesia, Cacumisporium, Chaetosphaeria, Chloridium, Craspedodidymum, Cryptophiale, Cryptophialoidea, Dictyochaetopsis, Minimidochium, and many published species of Codinaea and Dictyochaeta.

Taxonomic and Phylogenetic Reassessment of Pyrgidium (Mycocaliciales) and Investigation of Ascospore Morphology

Mycocaliciales comprise non-lichenized either saprotrophic or lichenicolous fungi which occur in temperate and tropical regions. The mazaediate, saprotrophic and monospecific genus, Pyrgidium, is currently assigned to this order, yet the phylogenetic placement of the genus has remained uncertain due to the absence of molecular data. In order to investigate the systematic position of Pyrgidium, two specimens collected in Brazil and Thailand, respectively, were used to generate mtSSU, SSU, LSU and ITS sequences. However, given that most other representatives of this order only have LSU and ITS sequences available, the phylogenetic reconstruction was limited to these two markers. The phylogenetic analyses confirmed placement of the genus within Mycocaliciales, the genus possessing a sister group relationship with the lichenicolous genus Sphinctrina. Detailed morphological descriptions and illustrations are provided, including those for type specimens of the various synonyms subsumed under the hitherto only accepted species, Pyrgidium montellicum (Beltr.) Tibell. The ascospore morphology was investigated using compound and scanning electronic microscopy (SEM). Principal component analysis (PCA) was performed for the ascospore size using PC-ORD 7. The molecular data and re-examination of the type specimens support the monospecific nature of this genus.

Novel Freshwater Ascomycetes from Spain

Freshwater ascomycetes are a group of fungi of great ecological importance because they are involved in decomposition processes and the recycling of organic matter in aquatic ecosystems. The taxonomy of these fungi is complex, with representatives in several orders of the phylum Ascomycota. In the present study, we collected ninety-two samples of plant debris submerged in freshwater in different locations in Spain. The plant specimens were placed in wet chambers and developed several fungi that were later isolated in pure culture. A main phylogenetic tree using the nucleotide sequences of D1-D2 domains of the 28S nrRNA gene (LSU) was built to show the taxonomic placement of all our fungal strains, and, later, individual phylogenies for the different families were built using single or concatenated nucleotide sequences of the most suitable molecular markers. As a result, we found a new species of Amniculicola that produces a coelomycetous asexual state, a new species of Elongatopedicellata that produces an asexual state, a new species of Neovaginatispora that forms both sexual and asexual states in vitro, and the sexual states of two species of Pyrenochaetopsis, none of which have been reported before for these genera. In addition, we describe a new species of Pilidium characterized by the production of copper-colored globose conidiomata, and of Pseudosigmoidea, which produces well-developed conidiophores.

Fourteen Unrecorded Species of Agaricales Underw. (Agaricomycetes, Basidiomycota) from the Republic of Korea

Agaricales species form pileate-stipitate fruiting bodies and play important roles in maintaining the terrestrial ecosystem as decomposers, symbionts, and pathogens. Approximately 23,000 Agaricales species have been known worldwide, and 937 species have been recorded in the Republic of Korea. However, most of them were identified solely based on morphological characteristics that often led to misidentifications. The specimens collected from 2018 to 2020 in the Republic of Korea were identified based on phylogenetic analysis of the internal transcribed spacer (ITS) sequences. Their identities were confirmed by microscopic characteristics. As a result, 14 Agaricales species were discovered for the first time in the Republic of Korea. They belonged to nine genera: Agaricus, Calocybe, Cortinarius, Hygrocybe, Inocybe, Lepista, Leucoagaricus, Marasmius, and Psathyrella. Detailed macroscopic and microscopic descriptions were provided to help distinguish these species. The morphological and molecular data provided in this study will serve as reliable references for the identification of Agaricales species.

Taxonomy of the anaerobic gut fungi (Neocallimastigomycota): a review of classification criteria and description of current taxa

Members of the anaerobic gut fungi (Neocallimastigomycota) reside in the rumen and alimentary tract of larger mammalian and some reptilian, marsupial and avian herbivores. The recent decade has witnessed a significant expansion in the number of described Neocallimastigomycota genera and species. However, the difficulties associated with the isolation and maintenance of Neocallimastigomycota strains has greatly complicated comparative studies to resolve inter- and intra-genus relationships. Here, we provide an updated outline of Neocallimastigomycota taxonomy. We critically evaluate various morphological, microscopic and phylogenetic traits previously and currently utilized in Neocallimastigomycota taxonomy, and provide an updated key for quick characterization of all genera. We then synthesize data from taxa description manuscripts, prior comparative efforts and molecular sequence data to present an updated list of Neocallimastigomycota genera and species, with an emphasis on resolving relationships and identifying synonymy between recent and historic strains. We supplement data from published manuscripts with information and illustrations from strains in the authors' collections. Twenty genera and 36 species are recognized, but the status of 10 species in the genera Caecomyces, Piromyces, Anaeromyces and Cyllamyces remains uncertain due to the unavailability of culture and conferre (cf.) strains, lack of sequence data, and/or inadequacy of available microscopic and phenotypic data. Six cases of synonymy are identified in the genera Neocallimastix and Caecomyces, and two names in the genus Piromyces are rejected based on apparent misclassification.

Morpho-Molecular Characterization of Microfungi Associated with Phyllostachys (Poaceae) in Sichuan, China

In the present study, we surveyed the ascomycetes from bamboo of Phyllostachys across Sichuan Province, China. A biphasic approach based on morphological characteristics and multigene phylogeny confirmed seven species, including one new genus, two new species, and five new host record species. A novel genus Paralloneottiosporina is introduced to accommodate Pa. sichuanensis that was collected from leaves of Phyllostachys violascens. Moreover, the newly introduced species Bifusisporella sichuanensis was isolated from leaves of P. edulis, and five species were newly recorded on bamboos, four species belonging to Apiospora, viz. Ap. yunnana, Ap. neosubglobosa, Ap. jiangxiensis, and Ap. hydei, and the last species, Seriascoma yunnanense, isolated from dead culms of P. heterocycla. Morphologically similar and phylogenetically related taxa were compared. Comprehensive descriptions, color photo plates of micromorphology are provided.

Characterization and rank assignment criteria for the anaerobic fungi (Neocallimastigomycota)

Establishing a solid taxonomic framework is crucial for enabling discovery and documentation efforts. This ensures effective communication between scientists as well as reproducibility of results between laboratories, and facilitates the exchange and preservation of biological material. Such framework can only be achieved by establishing clear criteria for taxa characterization and rank assignment. Within the anaerobic fungi (phylum Neocallimastigomycota), the need for such criteria is especially vital. Difficulties associated with their isolation, maintenance and long-term storage often result in limited availability and loss of previously described taxa. To this end, we provide here a list of morphological, microscopic, phylogenetic and phenotypic criteria for assessment and documentation when characterizing newly obtained Neocallimastigomycota isolates. We also recommend a polyphasic rank-assignment scheme for novel genus-, species- and strain-level designations for newly obtained Neocallimastigomycota isolates.

Morphological and Phylogenetic Analyses Reveal Five New Species in Chaetosphaeriaceae

Chaetosphaeriaceae is a genera-rich and highly diverse group of fungi with a worldwide distribution in terrestrial and aquatic habitats. Eight fresh collections of Chaetosphaeriaceae were obtained during investigations of hyaline-spored hyphomycetes in China and Thailand. Based on morphological characteristics and phylogenetic analysis of a combined LSU and ITS sequence dataset, Chaetosphaeria obovoidea, Codinaea aseptata, Codinaeella hyalina, Dictyochaeta guizhouensis and Paragaeumannomyces guttulatus were introduced as new species, Codinaea terminalis was reported as new host record, and Codinaea dwaya and Phialosporostilbe scutiformis were introduced as new collections. Phylogenetic analysis in this study revealed that Chaetosphaeria was polyphyletic. Detailed descriptions and illustrations of new taxa and identified species are provided, as well as an updated phylogenetic tree to confirm the placements of these eight new collections.

Bambusicolous Fungi in Pleosporales: Introducing Four Novel Taxa and a New Habitat Record for Anastomitrabeculia didymospora

While conducting a survey of bambusicolous fungi in northern Thailand and southwestern China, several saprobic fungi were collected from dead branches, culms and twigs of bamboos, which were preliminarily identified as species belonging to Pleosporales (Dothideomycetes) based on a morphological approach. Multigene phylogenetic analyses based on ITS, LSU, SSU, rpb2, tef1-α and tub2 demonstrated four novel taxa belonging to the families Parabambusicolaceae, Pyrenochaetopsidaceae and Tetraploasphaeriaceae. Hence, Paramultiseptospora bambusae sp. et gen. nov., Pyrenochaetopsis yunnanensis sp. nov. and Tetraploa bambusae sp. nov. are introduced. In addition, Anastomitrabeculia didymospora found on bamboo twigs in terrestrial habitats is reported for the first time. Detailed morphological descriptions and updated phylogenetic trees of each family are provided herein.

Dendrocorticiopsisorientalis gen. et sp. nov. of the Punctulariaceae (Corticiales, Basidiomycota) revealed by molecular data

Dendrocorticiopsisorientalis is presented in this study as a new genus and new species based on morphological and phylogenetic evidence. This new taxon is characterized by resupinate, smooth and membranaceous basidiomata, monomitic hyphal system with clamps, colorless dendrohyphidia, variable presence of cystidia, and ellipsoid to ovoid basidiospores measuring 5-7 × 3.2-5.2 μm. The phylogenetic analyses based on the ITS1-5.8S-ITS2 (ITS) + nuclear 28S rDNA (28S) dataset of Corticiales indicated that the new taxon is nested in Punctulariaceae, separated from other genera with strong support values. Descriptions, specimen photo, and illustrations of the new taxon are provided in this study. A morphological comparison of the four genera of Punctulariaceae is given.

Systematic revision of the Roseinae clade of Russula, with a focus on eastern North American taxa

The Roseinae clade is a lineage of the genus Russula primarily composed of species of Russula subsect. Roseinae. Species in this morphologically distinct clade possess a white to pale cream spore print, mild taste, positive reaction to sulfovanillin, and primordial hyphae with acid-resistant crystals in the pileipellis. Here, we present a morphological and phylogenetic assessment that distinguishes seven eastern North American species of the core Roseinae lineage and a new subsection, Russula subsection Albidinae, to accommodate members of the Albida clade. We assign the previously described species R. peckii, R. rubellipes, and R. pseudopeckii to three species-level clades, and three other species, R. cardinalis, R. cordata, and R. rheubarbarina, are described as new. Comparative morphological analyses reveal differences in the conformation of terminal elements in the pileipellis, spore size, hymenial cystidia contents, and pigmentation on the stipe surface as key features to recognize species in the group. Based on the analysis of publicly available data, we recognize a potential total of nine temperate North American species within R. subsect. Roseinae, in addition to four from Central America, two from Europe, and 14 from Asia.