Two Previously Unrecorded Fungal Species Isolated from Muui Island in Korea.

Fungi are cosmopolitan and they occupy diverse niches as consumers, producers, and decomposers. They play critical roles in the environment by enabling nutrient cycling and generating a plethora of secondary metabolites. This study aimed to identify and characterize fungal strains isolated from diverse sources on Muui Island, Republic of Korea. In 2023, a total of 86 fungal strains were collected and examined. Investigation of the morphological features and phylogenetic analyses of multiple barcode loci identified one putative novel species and two species previously unrecorded in the Republic of Korea: Colletotrichum sp., Colletotrichum guizhouense, and Fusarium brachygibbosum. This study provides a comprehensive description of their molecular phylogenies and morphological characteristics. These findings will contribute to the existing knowledge about fungal species in the Republic of Korea and future research on the fungal diversity on Muui Island.

The complete mitochondrial genome of the poisonous mushroom Trichoderma cornu-damae (Hypocreaceae).

Trichoderma cornu-damae is a poisonous mushroom that contains trichothecene mycotoxins. The complete mitochondrial genome of this mushroom was determined using next-generation sequencing. This mitogenome is a circular molecule 94,608 bp in length with a GC content of 27.94% and contains 15 protein-coding genes, two rRNA genes (rnl and rns), and 25 tRNA genes. Phylogenetic analysis placed T. cornu-damae in the family Hypocreaceae group, which includes the genus Trichoderma. The mitogenome of T. cornu-damae will contribute to our understanding of the phylogeny, taxonomy, and population genetics of this mushroom.

Complete mitochondrial genome sequence of Gymnopilus junonius.

Gymnopilus junonius, a well-known poisonous mushroom, is distributed worldwide. It contains a hallucinogenic alkaloid psilocybin and several other bioactive compounds. The mitochondrial genome, a circular DNA molecule of 161,145 bp, comprises 15 protein-coding genes, 24 transfer RNA genes, and 2 ribosomal RNA genes. The guanine-cytosine content was 31.56%. Based on the mitochondrial genome sequence, a phylogenetic tree was constructed to demonstrate the phylogenetic relationship. In this study, the phylogenetic positions of G. junonius and its related genera were determined.

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.

Influence of Season and Soil Properties on Fungal Communities of Neighboring Climax Forests (Carpinus cordata and Fraxinus rhynchophylla).

Trees in forest ecosystems constantly interact with the soil fungal community, and this interaction plays a key role in nutrient cycling. The diversity of soil fungal communities is affected by both environmental factors and host tree species. We investigated the influence of both of these factors by examining the total fungal communities in the rhizospheric soil of climax tree species that have similar ecological roles (Carpinus cordata, an ectomycorrhizal [ECM] tree, and Fraxinus rhynchophylla, an arbuscular mycorrhizal [AM] tree) in temperate forests with continental climates of Mt. Jeombong, South Korea. Fungal communities were assessed by Illumina-MiSeq sequencing the internal transcribed spacer (ITS) region of environmental DNA, and comparing their environmental factors (season and soil properties). We found that soil fungi of the two forest types differed in terms of community structure and ecological guild composition. The total fungal community composition changed significantly with seasons and soil properties in the F. rhynchophylla forest, but not in the C. cordata forest. However, potassium and carbon were significantly correlated with fungal diversity in both forests, and a positive correlation was found only between symbiotrophs of C. cordata and the carbon to nitrogen (C/N) ratio. Thus, the effects of environmental factors on soil fungal communities depended on the host trees, but some factors were common in both forests. Our results indicate that individual tree species should be considered when anticipating how the fungal communities will respond to environmental change.

Comparison of Soil Higher Fungal Communities between Dead and Living Abies koreana in Mt. Halla, the Republic of Korea.

To improve our understanding of the relationship between soil higher fungi (belonging to Ascomycota and Basidiomycota) and Abies koreana, we surveyed A. koreana soil fungal communities in a forest in Mt. Halla, Jeju Island, Korea by next-generation sequencing (Illumina Miseq). To confirm the soil higher fungal communities, we collected two types of soils from a defined plot: soils with dead (AKDTs) and living A. koreana (AKLTs), respectively. Soil fungi were classified into 2 phyla, 19 classes, 64 orders, 133 families, 195 genera, and 229 OTUs (895,705 sequence reads). Nonmetric multidimensional scaling (NMDS) showed significantly different soil higher fungal communities between AKDTs and AKLTs (p < .05). In addition, the saprophyte composition was significantly affected by A. koreana status (p < .05). The proportion of the mycorrhizal Clavulina spp. was different between soils with AKDTs and AKLTs, suggesting that Clavulina spp. may be a crucial soil fungal species influencing A. koreana. This study will lead to a better understanding of the ecological status of A. koreana in Mt. Halla. In addition, this study could be useful for the conservation and management of A. koreana habitats.

Macrofungal Survey of the Tian Shan Mountains, Kyrgyzstan.

The Tian Shan mountain system is one of the large mountain ranges located in Central Asia. This region is globally recognized as mountain ranges, offering inestimable wealth in fauna and flora with significant biodiversity values. We surveyed macrofungal diversity of Tian Shan in Kyrgyzstan from 2016 to 2018. A collection of macrofungi was made, and these were subjected to sequence comparisons and phylogenetic analysis to ensure the identity of the collected macrofungi. Of those collected, 95 out of 100 specimens were successfully sequenced and compared with those of other related species retrieved from GenBank. The sequenced specimens were classified into 2 phyla, 8 orders, 24 families, 47 genera, and 57 species, based on current taxonomic concepts (combining morphology and phylogeny). To the best of our knowledge, this study provides the first well-documented checklist and phylogenetic analysis of macrofungi recovered from the Tian Shan mountains in Kyrgyzstan.

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.

The complete mitochondrial genome of Sanghuangporus sanghuang (Hymenochaetaceae, Basidiomycota).

Sanghuang is a polypore mushroom, which has been widely used in oriental medicine. Since recent molecular phylogenetic studies elucidated its species delimitation, Sanghaungporus sanghuang became the official name of this fungus. In this study, the complete sequence of the mitochondrial DNA of S. sanghuang was determined. The whole genome was 112,060 bp containing 14 proteins, 2 ribosomal RNA subunits, and 45 transfer RNAs. The overall GC content of the genome was 23.21%. A neighbour-joining tree based on atp6 sequence data showed its close relationship with the species of Ganoderma and Trametes.

Kretzschmaria quercicola sp. nov., an Undescribed Fungus from Living Oak in Mt. Daeryong, Korea.

We encountered an unfamiliar ascomycete fruiting body, fitting characteristics of the genus Kretzschmaria, which features in a stipitate ascigerous stroma with carbonaceous interior and disintegrating perithecia. In this study, we report and characterize a new species of the decaying fungus. Compared to other species, one of the notable features of this specimen (TPML150908-046) is its stromatal size (up to 15 cm). Although TPML150908-046 is morphologically similar to K. milleri and K. sandvicensis, it differs sharply from both species in apical ring size (TPML150908-046, 6.5~10.5 µm; K. milleri, 11~16 µm) and ascospore width (TPML150908-046, 10.5~17 µm; K. sandvicensis, 8.5~11.5 µm). Phylogenetic trees based on ß-tubulin, ITS, and RPB2 sequences showed that our collection clustered with K. sandvicensis, with the respective similarities for these sequences being 95.6%, 91.3%, and 97.7%, signifying it as another species. With these results, we report it as a new species, which we call Kretzschmaria quercicola sp. nov.

Species identity of Phellinus linteus (sanghuang) extensively used as a medicinal mushroom in Korea.

Sanghuang is a medicinal mushroom that has gained particular attention in Korea. It has been extensively studied for the past few decades as a natural immune booster and cancer suppressor. Although the scientific name, Phellinus linteus, has been commonly used to refer to the sanghuang mushroom, the species identity of sanghuang has been called into question due to the ambiguity of its circumscription and the inadequacy of morphological distinctions within allied species. Because the species concept of sanghuang has been elucidated by recent molecular phylogenetic studies, it has become necessary to clarify the taxonomic positions of sanghuang strains extensively utilized in Korea. We conducted a phylogenetic analysis of 74 strains belonging to the P. linteus-baumii complex based on ITS nrDNA sequences. Parental stains of sanghuang varieties formally registered in the Korea Seed & Variety Service, including ASI 26046 (Corea sanghuang), 26114 (Boolro), and 26115 (HK 1-ho) were grouped with Sanghuangporus sanghuang instead of P. linteus in the inferred phylogeny.

New Records of Xylaria Species in Korea: X. ripicola sp. nov. and X. tentaculata.

During a Korean mushroom diversity survey from 2011 to 2014, we found one new Xylaria species (X. ripicola sp. nov.) and one Xylaria species that had not been previously observed in Korea (X. tentaculata). To confirm the phylogenetic placement of the new species, we conducted a phylogenetic investigation based on internal transcribed spacer regions of ribosomal DNA sequences. Additionally, the new species, X. ripicola, was subsequently analyzed for RNA polymerase II subunit sequences. We also evaluated the macroscopic and microscopic features of this species. Herein, X. ripicola is described as a new species that was collected from a natural beach habitat and X. tentaculata is formally reported as newly found in Korea.

Studies on seasonal dynamics of soil-higher fungal communities in Mongolian oak-dominant Gwangneung forest in Korea.

We surveyed macrofungi biweekly at defined plots from April to December in 2014, in the Mongolian oak-dominant forest, Gwangneung Forest, Pochen-si, Korea, and analyzed a soilhigher fungal diversity during four seasons (represented by April, August, October, and December). Based on morphological observation of collected specimens, the collected macrofungi were classified into 2 phyla 3 classes 7 orders, 14 families, 21 genera, and 33 species (36 specimens). DNA-based community analyses indicated that soil-higher fungi were classified into 2 phyla, 18 classes, 49 orders, 101 families, and 155 genera (83,360 sequence reads), defined herein as 155 genus-level operational taxonomic units (GOTUs). In the present study, we evaluated and discussed the fungal diversity in seasonal dynamics and soil layers based on collected macrofungi and pyrosequencing data while considering environmental parameters (pH, exchangeable K, T-P, NH 4 (+) , NO 3 (-) , OM, WR, TOC, and T-N). Moreover, principal components analysis (PCA) showed distinct clusters of the GOTU assemblage associated with the seasons.

Mushroom Flora of Ulleung-gun and a Newly Recorded Bovista Species in the Republic of Korea.

We conducted five times surveys, in June, September and October in 2012; June and September 2013, to catalog the mushroom flora in Ulleung-gun, Republic of Korea. More than 400 specimens were collected, and 317 of the specimens were successfully sequenced using the ribosomal DNA internal transcribed spacer barcode marker. We also surveyed the morphological characteristics of the sequenced specimens. The specimens were classified into 2 phyla, 7 classes, 21 orders, 59 families, 122 genera, and 221 species, and were deposited in the herbarium of Korea National Arboretum. Among the collected species, 72% were saprophytic, 25% were symbiotic, and 3% were parasitic. The most common order was Agaricales (189 specimens, 132 species), followed by Polyporales (47 specimens, 27 species), Russulales (31 specimens, 22 species), Boletales (10 specimens, 7 species), and so on. Herein, we also reported the first Bovista species in Korea, which was collected from Dokdo, the far-eastern island of Korea.

Taxonomic Re-evaluation of Megacollybia Species in Korea.

The diversity of the genus Megacollybia in Korea was examined based on morphological observation and analysis of molecular data. Currently, the genus is consisted of nine species with a global distribution. However, only M. platyphylla has been reported in the floral survey of Korea. During our re-evaluation of the taxonomic diversity of Megacollybia in Korea, six Megacollybia specimens collected in 2012 were identified based on internal transcribed spacer (ITS) sequences and morphology. Here, we report two Megacollybia species, M. clitocyboidea and M. marginata, as newly recorded species from Korea. The microscopic features of the two species are provided in this study. To our knowledge, this is the first phylogenetic analysis of Korean Megacollybia species.

Four Newly Recorded Amanita Species in Korea: Amanita sect. Amanita and sect. Vaginatae.

We collected nearly 70 specimens of Amanita species during a diversity study of Korean mushrooms conducted in 2012. In this study, we primarily investigated 23 Amanita specimens belonging to sections Amanita and Vaginatae. Based on sequence data of the internal transcribed spacers and partial large subunit of ribosomal RNA and morphological characteristics, we identified the following 15 phylogenetic species: A. alboflavescens, A. ceciliae, A. farinosa, A. fulva, A. griseofolia, A. ibotengutake, A. melleiceps, A. orientifulva, A. pantherina, A. rubrovolvata, A. sinensis, A. subglobosa, A. vaginata, A. cf. vaginata f. alba, and an undescribed Amanita species. In this study, four of the identified Amanita species (A. griseofolia, A. ibotengutake, A. orientifulva, and A. sinensis) were reported for the first time in Korea.

Taxonomic study of amanita subgenus lepidella and three unrecorded amanita species in Korea.

Amanita Pers. is a well-known monophyletic mushroom genus with a broad distribution. However, the diversity of Korean Amanita species has been underestimated, and most taxonomic studies conducted in Korea have only investigated their morphological characteristics. This approach is frequently insufficient for correct identification in fungal classification; therefore, we constructed a phylogeny of Amanita subgen. Lepidella in order to understand the phylogenetic placements of 16 Amanita specimens collected in Korea in 2012. The phylogeny constructed using the sequence data of the internal transcribed spacers and the partial large subunit of ribosomal RNA identified nine Amanita species (A. citrina, A. excelsa var. spissa, A. flavipes, A. fritillaria, A. oberwinklerana, A. pallidorosea, A. rubescens, A. subjunquillea, and A. volvata); of these, A. fritillaria, A. oberwinklerana, and A. pallidorosea are new to Korea.