Aspicilia humida Lee is described as a new lichen-forming fungus from a wetland forest, South Korea. The new species is distinguishable from Aspicilia aquatica (Fr.) Körb., the most similar species, by the absence of prothallus, black disk without green color in water, olivebrown epihymenium, shorter hymenium, hymenium I þ yellowish blue-green, wider paraphysial tips without a vivid pigment, smaller asci, smaller ascospores, and the presence of stictic acid. Molecular analyses employing internal transcribed spacer (ITS) and mitochondrial small subunit (mtSSU) sequences strongly support A. humida as a distinct species in the A. cinerea group. A surrogate key is provided to assist in the identification of all 28 aspicilioid species of Korea.

Lichens play crucial roles in the ecosystems, contributing to soil formation and nutrient cycling, and being used in biomonitoring efforts to assess the sustainability of ecosystems including air quality. Previous studies on heavy metal accumulation in lichens have mostly relied on manipulated environments, such as transplanted lichens, leaving us with a dearth of research on how lichens physiologically respond to heavy metal exposure in their natural habitats. To fill this knowledge gap, we investigated lichens from two of South Korea’s geo graphically distant regions, Gangwon Province and Jeju Island, and examined whether differ ence in ambient heavy metal concentrations could be detected through physiological variables, including chlorophyll damage, lipid oxidation, and protein content. The physio logical variables of lichens in response to heavy metals differed according to the collection area: Arsenic exerted a significant impact on chlorophyll degradation and protein content. The degree of fatty acid oxidation in lichens was associated with increased Cu concentra tions. Our research highlights the value of lichens as a bioindicator, as we found that even small variations in ambient heavy metal concentrations can be detected in natural lichens. Furthermore, our study sheds light on which physiology variables that can be used as indi cators of specific heavy metals, underscoring the potential of lichens for future ecology studies.

In this paper, we describe Endocarpon subramulosum as a new species from temperate regions of South Korea, which grows over soil on rocks. The proposed new species is morphologically similar to E. ramulosum Harada, which has so far been reported from Japan.
Classification ; Fungi* ; Japan ; Lichens* ; Republic of Korea* ; Soil

The study introduces the genus Mycobilimbia, from South Korea. M. philippina is reported here as being new to the country. Characteristic features of the species are crustose thallus, globose apothecia, K-proper exciple and hypothecium, Biatora-type asci, 3-septate fusiform ascospores, and a lack of secondary compounds.
Republic of Korea

The lichen species Polychidium muscicola was found in South Korea for the first time and this is the first record of the genus Polychidium from the Korean peninsula. This species is characterized by a dichotomously branched minute thallus with clustered cells of Nostoc as the photobiont. A detailed description and illustrations of this species are provided.
Lichens ; Nostoc ; Republic of Korea

Arthonia coreana, Arthonia superpallens, and Arthonia zelkovae are new species from South Korea. All new species are in the Euarthonia tribe, based on the key characteristics of colorless hypothecium and multi-cellular spores. A. coreana has a dull brownish hypophloedal thallus without bleaching and rounded or curved big apothecia in comparison with those of Arthonia punctiformis. A. coreana consistently exhibits 4-septate ascospores, which is a distinctive characteristic that distinguishes it from other Arthonia species. A. superpallens has a white-greenish thallus, pale yellowish apothecia, and a trentepohlioid alga. However, A. superpallens has no distinct prothallus, adnate, and convex apothecia, no pycnidia, and is UV-, in contrast with related species in the Arthonia antillarum group. A. zelkovae has a white, epiphloedal thallus, brownish-black epruinose apothecia covered with a whitish bark layer, and smaller ascospores in comparison with those of A. punctiformis. A. zelkovae consists of a chlorococcoid alga, which differs from related Arthonia species such as A. punctiformis, Arthonia pinastri, and Arthonia glaucella. Although A. zelkovae is similar to Arthonia dispersa in its white-colored thallus, blackish apothecia, and the presence of a chlorococcoid photobiont, A. zelkovae differs from the latter in having larger-sized 3-septate ascospores. Arthonia cinnabarina f. marginata, A. glaucella, Arthonia ilicinella, Arthonia lapidicola, Arthonia leioplacella, Arthonia pertabescens, A. pinastri, Arthonia spadicea, and Arthonia stellaris are newly described in Korea. The diagnostic characteristics of these species are discussed and presented. An artificial key is provided to facilitate identification of Arthonia species from Northeast Asia.
Asia ; Korea* ; Spores ; Ulmaceae

The genus Candelaria is characterized by a micro-foliose to micro-fruticose thallus and contains eight species, two of which were reported in South Korea. During the excursion of a Korean lichen flora investigation, some suspected Candelaria concolor specimens were collected, and their morphological, chemical, molecular phylogenetic, and geographic analyses were conducted. The samples eventually proved to be a new species, Candelaria asiatica, which can be recognized by a small, yellow lobate thallus with a pulverulent surface, and a fragile lobe margin with blastidia or phyllidia-like lobules.
Asia ; Classification ; Korea* ; Lichens ; Phylogeny

Lichen is a symbiotic mutualism of mycobiont and photobiont that harbors diverse organisms including endolichenic fungi (ELF). Despite the taxonomic and ecological significance of ELF, no comparative investigation of an ELF community involving isolation of a pure culture and high-throughput sequencing has been conducted. Thus, we analyzed the ELF community in Parmotrema tinctorum by culture and metabarcoding. Alpha diversity of the ELF community was notably greater in metabarcoding than in culture-based analysis. Taxonomic proportions of the ELF community estimated by metabarcoding and by culture analyses showed remarkable differences: Sordariomycetes was the most dominant fungal class in culture-based analysis, while Dothideomycetes was the most abundant in metabarcoding analysis. Thirty-seven operational taxonomic units (OTUs) were commonly observed by cultureand metabarcoding-based analyses but relative abundances differed: most of common OTUs were underrepresented in metabarcoding. The ELF community differed in lichen segments and thalli in metabarcoding analysis. Dissimilarity of ELF community intra lichen thallus increased with thallus segment distance; inter-thallus ELF community dissimilarity was significantly greater than intra-thallus ELF community dissimilarity. Finally, we tested how many fungal sequence reads would be needed to ELF diversity with relationship assays between numbers of lichen segments and saturation patterns of OTU richness and sample coverage. At least 6000 sequence reads per lichen thallus were sufficient for prediction of overall ELF community diversity and 50,000 reads per thallus were enough to observe rare taxa of ELF.

Heterodermia squamulosa (Degel.) W.L. Culb. was found in the mountain of Gariwang, Gangwon province, in 2008. It is characterized by numerous squamules along the margin, decorticate and white lower surface, rhizines along the margin, black and densely squarrosely branched, usually forming a dense mat under the thallus. Apothecia margins densely squamulose, ascospores 12~15 x 25~30 microm. Atranorin and zeorin contained in thallus. This is the first record of this species in South Korea.
Ascomycota ; European Continental Ancestry Group ; Humans ; Hydroxybenzoates ; Korea ; Republic of Korea ; Triterpenes

Cryptothecia austrocoreana is a new lichen species from South Korea. The species is characterized by the presence of a heteromerous thallus and faveolate ascigerous area (ascomata) immersed in a slightly raised thallus. The species has muriform ascospores, (4)6–8–spored 8–11 × 3–4 septate, (34)36–48(51) × (17)19–23(25) μm. Atranorin, chloroatranorin, and barbatic acid are present. In the phylogenetic tree, C. austrocoreana belongs to the arthonioid clade in Arthoniaceae.
Korea* ; Lichens ; Trees