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.

Re-Identification on Korean Penicillium Sequences in GenBank Collected by Software GenMine

Penicillium species have been actively studied in various fields, and many new and unrecorded species continue to be reported in Korea. Moreover, unidentified and misidentified Korean Penicillium species still exist in GenBank. Therefore, it is necessary to revise the Korean Penicillium inventory based on accurate identification. We collected Korean Penicillium nucleotide sequence records from GenBank using the newly developed software, GenMine, and re-identified Korean Penicillium based on the maximum likelihood trees. A total of 1681 Korean Penicillium GenBank nucleotide sequence records were collected from GenBank. In these records, 1208 strains with four major genes (Internal Transcribed Spacer rDNA region, b-tubulin, Calmodulin and RNA polymerase II) were selected for Penicillium reidentification. Among 1208 strains, 927 were identified, 82 were identified as other genera, the rest remained undetermined due to low phylogenetic resolution. Identified strains consisted of 206 Penicillium species, including 156 recorded species and 50 new species candidates. However, 37 species recorded in the national list of species in Korea were not found in GenBank. Further studies on the presence or absence of these species are required through literature investigation, additional sampling, and sequencing. Our study can be the basis for updating the Korean Penicillium inventory.

Determination of Diversity, Distribution and Host Specificity of Korean Laccaria Using Four Approaches

The genus Laccaria (Hydnangiaceae, Agaricales) plays an important role in forest ecosystems as an ectomycorrhizal fungus, contributing to nutrient cycles through symbiosis with many types of trees. Though understanding Laccaria diversity and distribution patterns, as well as its association with host plants, is fundamental to constructing a balanced plant diversity and conducting effective forest management, previous studies have not been effective in accurately investigating, as they relied heavily on specimen collection alone. To investigate the true diversity and distribution pattern of Laccaria species and determine their host types, we used four different approaches: specimen-based analysis, open database search (ODS), NGS analysis, and species-specific PCR (SSP). As a result, 14 Laccaria species have been confirmed in Korea. Results regarding the species distribution pattern were different between specimen-based analysis and SSP. However, when both were integrated, the exact distribution pattern of each Laccaria species was determined. In addition, the SSP revealed that many Laccaria species have a wide range of host types. This study shows that using these four different approaches is useful in determining the diversity, distribution, and host of ECM fungi. Furthermore, results obtained for Laccaria will serve as a baseline to help understand the role of ECM fungi in forest management in response to climate change.

Investigation of the Fungal Diversity of the Federated States of Micronesia and the Construction of an Updated Fungal Inventory

The Federated States of Micronesia (FSM) is an island country in the western Pacific and is a known biodiversity hotspot. However, a relatively small number of fungi (236 species) have been reported till July 2021. Since fungi play major ecological roles in ecosystems, we investigated the fungal diversity of FSM from various sources over 2016 and 2017 and constructed a local fungal inventory, which also included the previously reported species.Fruiting bodies were collected from various host trees and fungal strains were isolated from marine and terrestrial environments. A total of 99 species, of which 78 were newly reported in the FSM, were identified at the species level using a combination of molecular and morphological approaches. Many fungal species were specific to the environment, host, or source. Upon construction of the fungal inventory, 314 species were confirmed to reside in the FSM. This inventory will serve as an important basis for monitoring fungal diversity and identifying novel biological resources in FSM.

Four Unrecorded Aspergillus Species from the Rhizosphere Soil in South Korea

The genus Aspergillus is commonly isolated from various marine and terrestrial environments;however, only a few species have been studied in rhizosphere soil. As part of the Korean indigenous fungal excavation project, we investigated fungal diversity from rhizosphere soil, focusing on Aspergillus species. A total of 13 strains were isolated from the rhizosphere soil of three different plants. Based on phylogenetic analysis of β-tubulin and calmodulin and morphological characteristics, we identified five Aspergillus species. A. calidoustus and A. pseudodeflectus were commonly isolated from the rhizosphere soil. Four species were confirmed as unrecorded species in Korea: A. calidoustus, A. dimorphicus, A. germanicus, and A. pseudodeflecuts. The detailed morphological descriptions of these unrecorded species are provided.

Taxonomic Revision of the Genus Lactifluus (Russulales, Basidiomycota) of South Korea

Lactifluus(Pers.) Roussel is an ectomycorrhizal genus that was recently recognized to be distinct from the genus Lactarius. To date, 226 Lactifluus species have been reported worldwide. Misidentification of Lactifluus species is common because of intraspecific morphological variation, cryptic diversity, and the limited number of taxonomic keys available. Molecular data are indispensable for species delimitation; a multilocus phylogenetic analysis showed that most Asian Lactifluus species are not conspecific with morphologically similar species present on other continents. In particular, Korea has misused European and North American Lactifluus names. In this study, we evaluated the taxonomy of Lactifluus in Korea using both morphological and multilocus molecular (ITS, nrLSU, rpb1, and rpb2) data.We examined 199 Lactifluus specimens collected between 1980 and 2016, and a total of 24 species across the four Lactifluus subgenera were identified. All Korean species are distinct and clearly separated from European and North American species. Five taxa corresponded to previously described species from Asia and the remaining 19 taxa are confirmed as new species. Herein, we provide keys to the Korean Lactifluus species within their subgenera, molecular phylogenies, a summary of diversity, and detailed description of the new species.

Four Unrecorded Aspergillus Species from the Rhizosphere Soil in South Korea

The genus Aspergillus is commonly isolated from various marine and terrestrial environments;however, only a few species have been studied in rhizosphere soil. As part of the Korean indigenous fungal excavation project, we investigated fungal diversity from rhizosphere soil, focusing on Aspergillus species. A total of 13 strains were isolated from the rhizosphere soil of three different plants. Based on phylogenetic analysis of β-tubulin and calmodulin and morphological characteristics, we identified five Aspergillus species. A. calidoustus and A. pseudodeflectus were commonly isolated from the rhizosphere soil. Four species were confirmed as unrecorded species in Korea: A. calidoustus, A. dimorphicus, A. germanicus, and A. pseudodeflecuts. The detailed morphological descriptions of these unrecorded species are provided.

Taxonomic Revision of the Genus Lactifluus (Russulales, Basidiomycota) of South Korea

Lactifluus(Pers.) Roussel is an ectomycorrhizal genus that was recently recognized to be distinct from the genus Lactarius. To date, 226 Lactifluus species have been reported worldwide. Misidentification of Lactifluus species is common because of intraspecific morphological variation, cryptic diversity, and the limited number of taxonomic keys available. Molecular data are indispensable for species delimitation; a multilocus phylogenetic analysis showed that most Asian Lactifluus species are not conspecific with morphologically similar species present on other continents. In particular, Korea has misused European and North American Lactifluus names. In this study, we evaluated the taxonomy of Lactifluus in Korea using both morphological and multilocus molecular (ITS, nrLSU, rpb1, and rpb2) data.We examined 199 Lactifluus specimens collected between 1980 and 2016, and a total of 24 species across the four Lactifluus subgenera were identified. All Korean species are distinct and clearly separated from European and North American species. Five taxa corresponded to previously described species from Asia and the remaining 19 taxa are confirmed as new species. Herein, we provide keys to the Korean Lactifluus species within their subgenera, molecular phylogenies, a summary of diversity, and detailed description of the new species.

Two New Species of Laccaria (Agaricales, Basidiomycota) from Korea

Species of Laccaria (Hydnangiaceae, Agaricales, and Basidiomycota) are well-known ectomycorrhizal symbionts of a broad range of hosts.Laccaria species are characterized by brown, orange, or purple colored basidiocarps, and globose or oblong, echinulate and multinucleate basidiospores. While some Laccaria species are easily identified at the species level using only the morphological characteristics, others are hard to distinguish at the species level due to small differences in morphology. Heretofore, tenLaccaria species have been reported in Korea. While studying the fungal diversity in the National Parks of Korea, two new Laccaria species were discovered. Species identification was done based on molecular analyses (ITS, 28S rDNA, rpb2, and tef1 ), then were confirmed by their corresponding morphologies. The two newly discovered Laccaria species are proposed here as Laccaria macrobasidia and Laccaria griseolilacina. The unique morphological characters of L. macrobasidia that distinguish it from its closely related species are orange-brown colored basidiocarp, long basidia and the absence of cheilocystidia. L. griseolilacina is characterized by a light grayish lavender-colored pileus and the absence of cheilocystidia. Two new species are described and illustrated in the present paper.

Penicillium from Rhizosphere Soil in Terrestrial and Coastal Environments in South Korea

Penicillium, the most common genus plays an important ecological role in various terrestrial and marine environments. However, only a few species have been reported from rhizosphere soil. As part of a project to excavate Korean indigenous fungi, we investigated rhizosphere soil of six plants in the forest (terrestrial habitat) and sand dunes (coastal habitat) and focused on discovering Penicillium species. A total of 64 strains were isolated and identified as 26 Penicillium species in nine sections based on morphological characteristics and the sequence analysis of b-tubulin and calmodulin. Although this is a small-scale study in a limited rhizosphere soil, eight unrecorded species and four potential new species have been identified. In addition, most Penicillium species from rhizosphere soil were unique to each plant. Penicillium halotolerans, P. scabrosum, P. samsonianum, P. jejuense, and P. janczewskii were commonly isolated from rhizosphere soil. Eight Penicillium species, P. aurantioviolaceum, P. bissettii, P. cairnsense, P. halotolerans, P. kananaskense, P. ortum, P. radiatolobatum, and P. verhagenii were recorded for the first time in Korea. Here, we provide the detailed morphological description of these unrecorded species.

Taxonomic Study of the Genus Pholiota (Strophariaceae, Basidiomycota) in Korea

The genus Pholiota (Strophariaceae, Basidiomycota) is made up of wood-rotting saprotrophic mushrooms characterized by a yellow or brown pileus with scales and/or slimy, and by a brownish smooth spore with a germ pore. However, these features are not enough to distinguish its species, or separate the genus Pholiota from other brown-spored wood-rotting genera such as Hypholoma and Stropharia. Although internal transcribed spacer (ITS) sequence-based identification has improved identification accuracy for species of Pholiota, most Pholiota species in Korea are reported based on morphological features. To evaluate the taxonomy of Pholiota species, we investigated 62 specimens collected from 1999 to 2019 in Korea using ITS sequence analysis and morphological observation. Twelve of the 16 recorded Pholiota species in Korea were identified. While eight species were clearly separated, the ITS analysis did not distinguish three in the Pholiota adiposa complex. Therefore, further investigation is required to distinguish these three species. ITS sequences deposited in GenBank confirm that P. highlandensis exists in Korea. The presence of the other four Pholiota species could not be confirmed through specimens or sequence information in GenBank. A taxonomic key and the ITS sequence data for Korean Pholiota species are included and can be good baselines for further research on Pholiota taxonomy and diversity.

Penicillium from Rhizosphere Soil in Terrestrial and Coastal Environments in South Korea

Penicillium, the most common genus plays an important ecological role in various terrestrial and marine environments. However, only a few species have been reported from rhizosphere soil. As part of a project to excavate Korean indigenous fungi, we investigated rhizosphere soil of six plants in the forest (terrestrial habitat) and sand dunes (coastal habitat) and focused on discovering Penicillium species. A total of 64 strains were isolated and identified as 26 Penicillium species in nine sections based on morphological characteristics and the sequence analysis of b-tubulin and calmodulin. Although this is a small-scale study in a limited rhizosphere soil, eight unrecorded species and four potential new species have been identified. In addition, most Penicillium species from rhizosphere soil were unique to each plant. Penicillium halotolerans, P. scabrosum, P. samsonianum, P. jejuense, and P. janczewskii were commonly isolated from rhizosphere soil. Eight Penicillium species, P. aurantioviolaceum, P. bissettii, P. cairnsense, P. halotolerans, P. kananaskense, P. ortum, P. radiatolobatum, and P. verhagenii were recorded for the first time in Korea. Here, we provide the detailed morphological description of these unrecorded species.

Taxonomic Study of the Genus Pholiota (Strophariaceae, Basidiomycota) in Korea

The genus Pholiota (Strophariaceae, Basidiomycota) is made up of wood-rotting saprotrophic mushrooms characterized by a yellow or brown pileus with scales and/or slimy, and by a brownish smooth spore with a germ pore. However, these features are not enough to distinguish its species, or separate the genus Pholiota from other brown-spored wood-rotting genera such as Hypholoma and Stropharia. Although internal transcribed spacer (ITS) sequence-based identification has improved identification accuracy for species of Pholiota, most Pholiota species in Korea are reported based on morphological features. To evaluate the taxonomy of Pholiota species, we investigated 62 specimens collected from 1999 to 2019 in Korea using ITS sequence analysis and morphological observation. Twelve of the 16 recorded Pholiota species in Korea were identified. While eight species were clearly separated, the ITS analysis did not distinguish three in the Pholiota adiposa complex. Therefore, further investigation is required to distinguish these three species. ITS sequences deposited in GenBank confirm that P. highlandensis exists in Korea. The presence of the other four Pholiota species could not be confirmed through specimens or sequence information in GenBank. A taxonomic key and the ITS sequence data for Korean Pholiota species are included and can be good baselines for further research on Pholiota taxonomy and diversity.

Three Unrecorded Species Belonging to Penicillium Section Sclerotiora from Marine Environments in Korea

Species that belong to Penicillium section Sclerotiora are commonly found in various terrestrial environments, but only a few have been reported in marine environments. Because the number of Penicillium species reported in marine environments is increasing, we investigated the diversity of Penicillium section Sclerotiora in marine environments in Korea. Based on sequence analyses of β-tubulin and calmodulin loci, 21 strains of section Sclerotiora were identified as P. bilaiae, P. daejeonium, P. exsudans, P. herquei, P. cf. guanacastense, P. mallochii, P. maximae, and P. viticola. Three of them were confirmed as new to Korea: P. exsudans, P. mallochii, and P. maximae. Here, we have provided detailed morphological descriptions of these unrecorded species.

Fungal Diversity and Enzyme Activity Associated with the Macroalgae, Agarum clathratum

Agarum clathratum, a brown macroalgae species, has recently become a serious environmental problem on the coasts of Korea. In an effort to solve this problem, fungal diversity associated with decaying A. clathratum was investigated and related β-glucosidase and endoglucanase activities were described. A total of 233 fungal strains were isolated from A. clathratum at 15 sites and identified 89 species based on morphology and a multigene analysis using the internal transcribed spacer region (ITS) and protein-coding genes including actin (act), β-tubulin (benA), calmodulin (CaM), and translation elongation factor (tef1). Acremonium, Corollospora, and Penicillium were the dominant genera, and Acremonium fuci and Corollospora gracilis were the dominant species. Fifty-one species exhibited cellulase activity, with A. fuci, Alfaria terrestris, Hypoxylon perforatum, P. madriti, and Pleosporales sp. Five showing the highest enzyme activities. Further enzyme quantification confirmed that these species had higher cellulase activity than P. crysogenum, a fungal species described in previous studies. This study lays the groundwork for bioremediation using fungi to remove decaying seaweed from populated areas and provides important background for potential industrial applications of environmentally friendly processes.

Macrolepiota in Korea: New Records and a New Species

The genus Macrolepiota (Agaricales, Basidiomycota) is easy to recognize at the genus level because of big, fleshy basidiocarps with squamules covering the pileus; a single or double annulus; and big, thick-walled basidiospores with a germ pore. However, morphological identification is often unreliable in Macrolepiota due to similar morphological features among species. Due to the uncertainty of previous morphological identification in the genus Macrolepiota, it is necessary to re-examine Korean Macrolepiota using molecular data. We re-examined 34 Macrolepiota specimens collected from 2012 to 2018 in Korea using a reverse taxonomic approach, whereby species identification was first done based on the internal transcribed spacer (ITS) region analysis, followed by morphological confirmation. We identified the presence of four species: M. detersa, M. mastoidea, M. procera, and M. umbonata sp. nov. Two species (M. detersa and M. mastoidea) were previously unrecorded from Korea and M. umbonata is a new species. Detailed descriptions of all four species and taxonomic key are provided in this study. Macrolepiota procera and M. umbonata are distributed through the country, but M. detersa and M. mastoidea are distributed only in limited areas. According to our results, the combination of ITS locus and morphology proved to be a robust approach to evaluate the taxonomic status of Macrolepiota species in Korea. Additional surveys are needed to verify the species diversity and clarify their geographic distribution.

First Report of Buchwaldoboletus lignicola (Boletaceae), a Potentially Endangered Basidiomycete Species, in South Korea

During the 2014 survey of the mushroom flora of Gwangneung forest in South Korea, we collected two specimens of boletoid mushroom growing on a felled tree of Pinus koraiensis. These specimens were characterized by a light brown to reddish-brown pileus with appressed tomentum, pore surface bluing instantly when bruised, golden-yellow mycelium at the base of stipe, and lignicolous habitat. Both specimens were identified as Buchwaldoboletus lignicola, a rare basidiomycete, based on morphological characteristics and sequences of internal transcribed spacer (ITS; fungal barcode). Here, we describe these specimens and provide the first report of this genus in South Korea.

First Report of Eight Milkcap Species Belonging to Lactarius and Lactifluus in Korea

Lactarius and Lactifluus are milkcaps that are characterized by the secretion of latex. These two genera are part of a globally distributed cosmopolitan group of ectomycorrhizal fungi that is an important food resource in various ecosystems. Recently, the taxonomy of Lactarius and Lactifluus has been revised based on molecular phylogenetics. Despite the importance of these taxa, Korean species of both genera are poorly understood. In an effort to describe milkcap species that are indigenous to Korea, a long-term study has been initiated. During a recent survey, eight species of milkcaps that were previously unrecorded in Korea were detected based on morphological observation and sequence analysis of the internal transcribed spacer region: five Lactarius species (Lactarius atromarginatus, L. austrotorminosus, L. kesiyae, L. tabidus, and L. vietus) and three Lactifluus species (Lactifluus acicularis, Lf. pilosus, and Lf. pinguis). Detailed morphological descriptions and phylogenetic relationships of these species are provided in this article.

Guild Patterns of Basidiomycetes Community Associated With Quercus mongolica in Mt. Jeombong, Republic of Korea

Depending on the mode of nutrition exploitation, major fungal guilds are distinguished as ectomycorrhizal and saprotrophic fungi. It is generally known that diverse environmental factors influence fungal communities; however, it is unclear how fungal communities respond differently to environment factors depend on fungal guilds. In this study, we investigated basidiomycetes communities associated with Quercus mongolica using 454 pyrosequencing. We attempted to detect guild pattern (ectomycorrhizal or saprotrophic fungal communities) by comparing the influence of geography and source (root and surrounding soil). A total of 515 mOTUs were detected from root (321) and soil (394) of Q. mongolica at three sites of Mt. Jeombong in Inje County. We found that patterns of diversity and community structure were different depending on the guilds. In terms of alpha diversity, only ectomycorrhizal fungi showed significant differences between sources. In terms of community structure, however, geography significantly influenced the ectomycorrhizal community, while source appeared to have a greater influence on the saprotrophic community. Therefore, a guild-based view will help to elucidates novel features of the relationship between environmental factors and fungal communities.

New Report of Three Unrecorded Species in Trichoderma harzianum Species Complex in Korea

The genus Trichoderma (Hypocreaceae, Ascomycota) consists of globally distributed fungi. Among them, T. harzianum, one of the most commonly collected Trichoderma species, had been known as a polyphyletic or aggregate species. However, a total of 19 species were determined from the polyphyletic groups of T. harzianum. Thus, we explored Korean “T. harzianum” specimens that were collected in 2013–2014. These specimens were re-examined based on a recent study with translate elongation factor 1-alpha (EF1α) sequences to reveal cryptic Trichoderma species in Korea. As a result, four different species, T. afroharzianum, T. atrobruneum, T. pyramidale, and T. harzianum, were identified. Except T. harzianum, the other three species have not been reported in Korea. In this work, we describe these species and provide figures.