Evidence highlighting the importance of gut microbiota in biodiversity conservation is growing; however, gut bacteria in South Korean wildlife have not been well identified. Using a culture-dependent isolation method, we identified the gut bacteria from Korean aquatic wildlife: the gazami crab (Portunus trituberculatus), Korean striped bitterling (Acheilognathus yamatsutae), oily bitterling (Acheilognathus koreensis), leopard mandarin fish (Siniperca scherzeri), Korean dark chub (Zacco koreanus), diving beetle (Cybister lewisianus), spotted steed (Abbottina springeri), and Korean spotted sleeper (Odontobutis obscura interrupta). We identified 18 strains previously unrecorded in South Korea by comparing 16S rRNA gene sequences of isolates against the EzBioCloud and National Institute of Biological Resources (NIBR) databases. The isolated strains belong to the phyla Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. We also assessed for phylogenetic relatedness, Gram-stain reaction, colony and cell morphology, and biochemical characteristics. Basic information and 16S rRNA gene sequences of the isolates were registered in NIBR, and NIBR accession numbers are provided.
During a comprehensive investigation of indigenous prokaryotic species in Korea, 25 and 10 bacterial strains assigned to the classes Alphaproteobacteria and Betaproteobacteria, respectively, were isolated from diverse environmental habitats, including soil, mud, tidal field, sea water, sand, rusted iron, and leaf. Based on their high 16S rRNA gene sequence similarities (>98.7%) and the formation of robust phylogenetic clades with type species, each strain was assigned to an independent and predefined bacterial species. Since there were no published or official reports regarding these 35 isolates in Korea, they - 25 species of 14 families in the 5 orders of Alphaproteobacteria and 10 species of 3 families in the two orders of Betaproteobacteria - have been reported as unrecorded species in Korea. In addition, Gram reaction, colony and cell morphology, basic biochemical characteristic, isolation source, and strain ID of each species are also described in the species description sections.
For the collection of indigenous prokaryotic species in Korea, 77 strains within the phylum Actinobacteria were isolated from various environmental samples, fermented foods, animals and clinical specimens in 2019. Each strain showed high 16S rRNA gene sequence similarity (>98.8%) and formed a robust phylogenetic clade with actinobacterial species that were already defined and validated with nomenclature. There is no official description of these 77 bacterial species in Korea. The isolates were assigned to 77 species, 31 genera, 18 families, 14 orders and 2 classes of the phylum Actinobacteria. All the strains except one Coriobacteriia strain were affiliated within the class Actinomycetia. Among them, the orders Streptomycetales and Microbacteriales were predominant. A number of strains were isolated from forest soils, riverside soils, and ginseng cultivated soils. Twenty-nine strains were isolated from ‘Protected Ecosystem and Scenery Areas’. Morphological properties, basic biochemical characteristics, isolation source and strain IDs are described in the species descriptions.
Diatoms have been used in examining water quality and environmental change in freshwater systems. Here, we analyzed molecular profiling of seasonal diatoms in the Han River, Korea, using the hypervariable region of 18S V1-V3 rRNA and pyrosequencing. Physicochemical data, such as temperature, DO, pH, and nutrients showed the typical seasonal pattern in a temperate region. In addition, cell counts and chlorophyll-a, were recorded at high levels in spring compared to other seasons, due to the diatom bloom. Metagenomic analysis showed a seasonal variation in the phytoplankton community composition, with diatoms as the most frequently detected in spring (83.8%) and winter (69.7%). Overall, diatom genera such as Stephanodiscus, Navicula, Cyclotella, and Discostella were the most frequent in the samples. However, a large number of unknown Thalassiosirales diatoms were found in spring (35.5%) and winter (36.3%). Our molecular profiling revealed a high number of diatom taxa compared to morphological observation. This is the first study of diatoms in the Han River using molecular approaches, providing a valuable reference for future study on diatoms-basis environmental molecular monitoring and ecology
A new species, Miscanthus wangpicheonensis of section Kariyasua, is described and illustrated from the morphological characteristics based on a type specimen collected from Gyeongsangbuk-do. This new species is similar to Miscanthus sacchariflorus (Maxim.) Hack., and M. longiberbis (Hack.) Nakai. The characters which distinguish the above two species are short leaves and racemes, callus hairs 1-1.5-times longer than spikelet, and well-developed awns of spikelet. The specific epithet, “wangpicheonensis”, is based on the name of the locality where the new species is found. We assume this new species originated from the hybridization of Miscanthus sacchariflorus (Maxim.) Hack., and M. longiberbis (Hack.) Nakai. Miscanthus wangpicheonensis is found in only one locality in Uljin-gun, Gyeongsangbuk-do, Republic of Korea.
Anteholosticha bergeri and Bakuella granulifera were isolated from soil samples collected from Muuidong and Songdo-dong, Incheon and confirmed new to South Korea. Including these two newly recorded species, 11 species of Anteholosticha and four species of Bakuella have been recorded in South Korea to date. Anteholosticha bergeri was discriminated from congeners by following characters: cortical granules, 12-16 macronuclei, 5-8 midventral pairs, 2-3 pretransverse cirri, 4-6 transverse cirri, and three dorsal kineties. Bakuella granulifera was identified by cortical granules, 5-11 buccal cirri, 2-5 frontoterminal cirri, 2-5 midventral cirri rows, and 8-12 transverse cirri. The Korean A. bergeri population corresponds to the Austrian population, except for the number of marginal and transverse cirri, and the Korean B. granulifera population corresponds to the Namibian population, except for body size. In addition, small subunit ribosomal RNA (18S rRNA) gene sequences from both species were determined.
Only four species of leuconids have been recorded in Korea, all belonging to the genera Eudorella Norman, 1867 and Nippoleucon Watling, 1991. In this study, Pseudoleucon japonicus Gamô, 1964 belonging to family Leuconidae Sars, 1878 is newly recorded for Korean cumacean fauna. Also, for the first time, the male of the species is fully described and illustrated. The specimens were collected from the exclusive economic zone (EEZ) in the western sea (Yellow Sea) of Korea, with a rectangular dredge during 2007-2008. This species is characterized by the following features: the carapace has strong serrations on the antero-lateral margin and a pair of short oblique ridges on the side surface; the ridges begin near the end of frontal lobe and merge with the dorsal median carina; the appendages, such as antenna 1, pereopod 2 and uropod have a lot of simple setae decorated with a bundle of hairs at the end. The present study represents the first record on the genus Pseudoleucon Zimmer, 1903 from Korea.
Heterorhabdus papilliger (Claus, 1863) is newly reported from the Tsushima Warm Current realm of the southern Korean waters. Its morphological diagnostic characteristics generally agreed well with the original description and the previous records of H. papilliger. The female of H. papilliger can be recognized by the genital somite, which in lateral view has a more or less rounded genital prominence and an uninflated posterior ventral margin; the second exopodal segment of male right leg 5 with the medial projection with a large, rounded, plumose proximal lobe, and a poorly developed distal lobe. The genetic difference for the partial mtCOI gene between Korean specimens and H. papilliger from Spain and Japan of the same clade is 0.4%, while the difference between Korean specimens is 0.5%. However, the interspecific difference for the mtCOI gene between H. papilliger from the Korean waters and the other Heterorhabdus species is in the range of 14.7-20.8%, suggesting that the former is a valid species.
The genus Pholcus Walckenaer, 1805 is the largest genus among the cellar spider family Pholcidae C.L.Koch, 1850, including 339 species. To date, 33 species in the genus are known to be distributed in Korea, being placed into three species-groups (crypticolens-group, phalangioides-group, and phungiformes-group). About 91% of these species are endemic to Korea. In this study, four new species of the genus Pholcus were discovered in Korea, viz, Pholcus chuncheonensis Lee, Choi and Kim sp. nov., Pholcus pajuensis Lee, Choi and Kim sp. nov., Pholcus pocheonensis Lee, Choi and Kim sp. nov., and Pholcus unaksanensis Lee, Choi and Kim sp. nov. These new species are classified as members of the phungiformes-group, having morphological characteristics such as male chelicerae with a frontal apophysis, palpal tibia with a prolateroventral tubercle, and genital bulb without appendix or having pseudo-appendix, but can be distinguished from congeners by characteristics of the male palp and female genitalia. Detailed descriptions and a key to new species are provided with accompanying photographs.