During a comprehensive study of indigenous prokaryotic species in South Korea, nine bacterial species in the phylum Bacteroidetes were isolated from freshwater environmental samples that were collected from three major rivers in the Republic of Korea. High 16S rRNA gene sequence similarity (${\geq}98.7%$) and robust phylogenetic clades with the closely related species suggest that each strain was correctly assigned to an independent and predefined bacterial species. There were no previous reports of these nine species in Korea. Within the phylum Bacteroidetes, four species were assigned to the genus Flavobacterium, order Flavobacteriales, and five species to three genera of two families in the order Cytophagales. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are described in the species description section.

Culturable bacterial diversity was investigated using freshwater and sediment samples collected from the North Han River basin in 2017, as a part of the research program 'Survey of freshwater organisms and specimen collection'. Over a thousand bacterial strains were isolated from the samples and identified based on 16S rRNA gene sequences. Among the bacterial isolates, 22 strains showing higher than 98.7% sequence similarity with validly published bacterial species, but not reported in Korea, were classified as unrecorded species in Korea. The 22 bacterial strains were phylogenetically diverse and assigned to 6 classes, 11 orders, 15 families, and 21 different genera. At the generic level, the unreported species were affiliated with Flavobacterium of the class Flavobacteria, Flexibacter of the class Cytophagia, Blastomonas, Brevundimonas, Elstera, Rhizobium, Roseomonas, Sphingomonas, and Xanthobacter of the class Alphaproteobacteria, Albidiferax, Cupriavidus, Curvibacter, Ferribacterium, Hydrogenophaga, Iodobacter, Limnohabitans, Polaromonas, Undibacterium, and Variovorax of the class Betaproteobacteria, Pseudomonas of the class Gammaproteobacteria, and Arcobacter of the class Epsilonproteobacteria. The unreported bacterial species were further characterized by examining Gram reaction, colonial and cellular morphology, and biochemical properties. The detailed descriptions of 22 strains of the unreported bacterial species are also provided.

Eight bacterial strains, 18JY8-13, 18JY13-16, 18JY43-7, 18JY12-7, 18JY1-1, 18JY1-7, 18JY15-3, and 18JY7-2 assigned to the phylum Firmicutes were isolated from a variety of soil samples collected in the Jeju Island, Korea. Cells of the eight strains were Gram-positive, aerobic and showed resistant to UV-radiation. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strains 18JY8-13, 18JY13-16, 18JY43-7, 18JY12-7, 18JY1-1, 18JY1-7, 18JY15-3, and 18JY7-2 were most closely related to Bacillus paranthracis(99.9%), Bacillus paramycoides(99.6%), Bacillus australimaris(99.9%), Bacillus wiedmannii (100%), Bacillus halosaccharovorans(99.6%), Bacillus deserti(98.7%), Bacillus cereus (99.8%), and Bacillus albus(100%), respectively. This is the first report of these eight species in Korea.

Eight bacterial strains assigned to the phylum Firmicutes were isolated from the soil samples in Korea. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains 18JY14-16, 18JY14-35, 18JY42-5, 18JY12-20, 18JY35-8, 18JY76-9, 18JY39-1 and 18JY54-12 were most closely related to Paenibacillus lupini (MH497638; 99.4%), Paenibacillus illinoisensis (MH497643; 99.8%), Paenibacillus tundrae (MH497658; 99.7%), Paenibacillus selenitireducens (MH497639; 99.4%), Paenibacillus eucommiae (MH 497640; 99.9%), Paenibacillus vini (MH497654; 99.4%), Paenibacillus gorillae (MH497647; 99.5%), and Paenibacillus macquariensis (MH497649; 99.9%) respectively. These Paenibacillus species were Gram-stain-positive, rod-shaped and radiation resistant bacteria. This is the first report of these nine bacterial species in Korea.

Six bacterial strains 18JY42-3, 18SH, 18JY76-11, 17J11-11, 18JY14-14, and 18JY15-11 assigned to the phylum Proteobacteria, Firmicutes, and Actinobacteria were isolated from soil samples in Korea. The Cohnella species, strain 18JY42-3 was Gram-stain-positive, short rod-shaped and beige-colored. The Methylobacterium species, strains 18SH and 18JY76-11 were Gram-stain-negative, short rod-shaped and pink-colored. The Microterricola species, strain 17J11-11 was Gram-stain-positive, short rod-shaped and yellow-colored. The Paenarthrobacter species, strains 18JY14-14 and 18JY15-11 were Gram-stain-positive, short rod-shaped and white-colored. Phylogenetic analysis based on 16S rRNA gene sequence showed that strains 18JY42-3, 18SH, 18JY76-11, 17J11-11, 18JY14-14, and 18JY15-11 were most closely related Cohnella rhizosphaerae (MH497628; 98.8%), Methylobacterium goesingense (MH497632; 99.1%), Methylobacterium populi (MH497635; 99.9%), Microterricolagilva (MH504108; 98.4%), Paenarthrobacter nicotinovorans (MH497641; 100%), and Paenarthrobacter nitroguajacolicus (MH497646; 99.2%), respectively. All the six unrecorded strains showed resistance to UV radiation. This is the first report of these six species in Korea.

While screening indigenous prokaryotic species in Republic of Korea in 2017, a total of 17 bacterial strains assigned to the phylum Bacteroidetes were isolated from a variety of environmental habitats including water of fountain, tidal flat, plant root, soil, the gut of Russian grayling butterfly, ginseng field, seawater, lagoon and seashore sand. From the 16S rRNA gene sequence similarity of more than 98.7% and the formation of a robust phylogenetic clade with the closest species, it was found that the 17 strains belong to independent and recognized bacterial species. There has been no official report that the identified 17 species have been previously isolated in the Republic of Korea. Thus, 15 species in 10 genera of one family in the order Flavobacteriales, one species in one genus of one family in the order Cytophagales, and one species in one genus of one family in the order Sphingobacteriales are proposed as unrecorded species of the phylum Bacteroidetes found in the Republic of Korea. Gram reaction, colony and cell morphology, basic phenotypic characteristics, isolation source, taxonomic status, strain ID and other information are described in the species descriptions.

Though several wood decay fungi have been reported in the world-wide, only about 600 wood decay fungi have been reported in Korea to date. Thus, the objective of this study was to secure resources for the wood decay fungi in Korea. We investigated wood decay fungi in Yeoninsan Provincial Park, Korea, and the collected specimens were identified based on ITS sequence analysis. Two species were unrecorded species in Korea: Postia hirsuta (Polyporales, Basidiomycota) and Hyphodontia reticulata (Hymenochaetales, Basidiomycota). Another species was previously reported without detailed description: Ceriporia alachuana (Polyporales, Basidiomycota). Here, we provided additional detailed microscopic features and phylogenetic analysis of these species.

A new species of Theridiidae, Carniella coreana sp. nov., is described and illustrated from Korea. The male of this newly described species is most similar to Carniella tsurui Ono, 2007 in the general shape of its palp, but can be distinguished by the winding structure of the embolus and broad tipped and twisted embolic apophysis. The genus Carniella Thaler & Steinberger, 1988 is newly recorded to Korean spider fauna.