Report of 21 unrecorded bacterial species in Korea belonging to the phylum Actinobacteria, discovered during the survey in 2020 Author Ham, You Ju Department of Microbiology and Molecular Biology, Chungnam National University, Daejeon 34134, Republic of Korea Author Jeong, Ji Won Department of Microbiology and Molecular Biology, Chungnam National University, Daejeon 34134, Republic of Korea Author Im, Wan-Taek Department of Biotechnology, Hankyong National University, Anseong 17579, Republic of Korea Author Kim, Won-Yong Department of Medicine, Chung-Ang University, Seoul 06974, Republic of Korea Author Yoon, Jeong-Hun Department of Food Molecular Biotechnology, Sungkyunkwan University, Suwon 16419, Republic of Korea Author Kim, Myung Kyum Department of Bio and Environmental Technology, Seoul Woman’s University, Seoul 01797, Republic of Korea Author Seong, Chi Nam Department of Biology, Sunchon National University, Suncheon 57922, Republic of Korea Author Kim, Seung Bum Department of Microbiology and Molecular Biology, Chungnam National University, Daejeon 34134, Republic of Korea text Journal of Species Research 2022 11 1 1 9 journal article 10.12651/JSR.2022.11.1.001 2713-8615 8120070 Description of Streptomyces phaeofaciens SM 6 Cells are Gram-stain-positive and filamentous. Colonies are filamentous, umbonate and cream colored after incu- bation for 3 days at 30℃. Positive for nitrate reduction; but negative for indole production, glucose fermentation, arginine dihydrolase, urease, esculin hydrolysis, gelatin hydrolysis β-galactosidase and cytochrome oxidase. D- Glucose, L-arabinose, D-mannose, D-mannitol, N -acetyl-glucosamine, D-maltose, potassium gluconate, adipic acid and malic acid are utilized as sole carbon sources; but not capric acid, trisodium citrate and phenylacetic acid. Strain SM6 ( = NIBRBAC000506150) was isolated from a wetland sample from Seoul . The GenBank accession number for the 16S rRNA gene sequence of strain SM6 is MW164956. Description of Streptomyces pseudogriseolus MMS 20-AI2-20 Cells are Gram-stain-positive and filamentous. Colonies are filamentous, raised, undulate and brown colored after incubation for 3 days on ISP2 at 30℃. Positive for nitrate reduction, arginine dihydrolase, urease, esculin hydrolysis and cytochrome oxidase; but negative for indole production, glucose fermentation, gelatin hydrolysis and β-galactosidase. D-Glucose, N -acetyl-glucosamine, D-maltose, potassium gluconate, capric acid and malic acid are utilized as sole carbon sources; but not L-arabinose, Dmannose, D-mannitol, adipic acid, trisodium citrate and phenylacetic acid. Strain MMS20-AI2-20 ( = NIBRBAC 000506174) was isolated from a soil sample from Okcheon-gun, Chungcheongbuk-do . The GenBank accession number for the 16S rRNA gene sequence of strain MMS20-AI2-20 is MW149078.