We conducted a taxonomic study of bdelloid rotifers found from terrestrial habitats such as mosses, leaf litter and soil at four different locations in Korea. The study resulted in four new Korean records belonging to two genera in two families, Habrotrochidae and Philodinidae, of bdelloid rotifers: Habrotrocha soror Donner, 1950; H. thienemanni rubella Donner, 1951; H. valida Milne, 1916 and Philodina nitida nitida Milne, 1916. These new Korean records are rare and have very limited distributions. Habrotrocha thienemanni rubella and H. valida were not found again after their original descriptions until the present study. The present study is the third record for both H. soror and P. nitida nitida. All these four new Korean records are new to Asian fauna as well. Here, diagnostic characteristics and photomicrographs are provided for each new Korean record. In addition, a partial sequence of mitochondrial cytochrome c oxidase subunit 1 gene (mtCOX1) for P. nitida nitida is presented.
Two known species of the family Comesomatidae Filipjev, 1918 were collected from marine sediments of the sublittoral zone in the East Sea, Korea and described and illustrated. Dorylaimopsis variabilis Muthumbi, Soetaert and Vincx, 1997, which was originally described from the Kenyan coast in the Indian Ocean, is recorded from the East Sea, Korea for the first time; there are only slight differences in amphidial fovea turns, body length, body width and relative length of tail. Setosabatieria hilarula (De Man, 1922), Platt, 1985, which was originally described from the North Sea, is recorded from the East Sea, Korea for the first time; there are only slight differences in the number of precloacal supplements, the relative length of tail and the posterior portion of tail. We provide pictorial keys for determination of valid species in the genera Dorylaimopsis Ditlevsen, 1918 and Setosabatieria Platt, 1985. This is the first description of the genus Dorylaimopsis and Setosabatieria from Korean waters.
A fern spore-feeding stathmopodid species, Calicotis latebrifica Terada, 2016 is reported for the first time from Korea on the basis of one male and three females from Island Chujado, Jeju Province. This record represents the third example of the Korean Lepidoptera associated with fern spores for larval food items. The species is similar to Cuprina fuscella Sinev, 1988 in feeding on fern spores but differs from the latter in the body color and the presence of cilia on the ventral side of antennal flagellum. The genus Calicotis is introduced for the first time to the Korean fauna. Calicotis latebrifica has been known exclusively from Japan before this study. Larval habits for feeding and shelter construction were demonstrated from field observation and rearing in captivity. A new host plant of C. latebrifica, Dryopteris nipponensis Koidz. is recorded. The habitus and genitalia of both sexes are briefly described for C. latebrifica with photographs.
A specimen of Henricia was collected from the adjacent waters of Moseulpo, Jeju Island, Korea, using fishing nets. The specimen was identified as Henricia aspera Fisher, 1906, which belongs to the family Echinasteridae of the order Spinulosida. This species can be distinguished from other Henricia species by its broad arms (R/r=4.1), swollen arm base, three to seven short abactinal spines, and close-meshed formation of the actinal skeleton. This study has newly recorded H. aspera inhabiting the Korean fauna, bringing the total number of known Henricia species in Korea to 16. This study provides a description of the morphological characteristics of H. aspera with photographs of each part. Additionally, a table is presented that compares the morphological characteristics of H. aspera with closely related Henricia species.
In March 2021, marine sediment from East Sea samples were suspended in a 2% NaCl solution, and serial dilution was performed in fresh marine and Reasoner’s 2A agar. Isolated bacterial strains were identified based on 16S rRNA gene sequences, and showed at least 98.7% sequence similarity with previously reported bacterial species. Finally, seven bacterial strains which were validly published but not reported in Korea, were obtained. These isolates were allocated to the orders Bacillales and Flavobacteriales. The three Flavobacteriales strains are classified into the family Flavobacteriaceae. The other four Bacillales belong to the families Bacillaceae and Paenibacillaceae. The seven unrecorded bacterial strains in this study are classified into seven different genera, which are assigned to Mesobacillus, Paenibacillus, Gramella, Gillisia, Arenibacter, Fictibacillus, and Brevibacillus. During the investigation, the possibility of excavation of various unrecorded species in domestic marine sediment was confirmed. Gram-staining, cell morphology, physiological and basic biochemical characteristics, and phylogenetic analysis were performed in this study and provided in the description of each strain.
Bacterial communities inhabiting islands play a vital role in the functioning and formation of a unique, isolated ecosystem. Nevertheless, there has been a lack of systematic research on the indigenous microbiological resources of the islands in Korea. To excavate microbial resources for further studies on the metabolism and biotechnological potential, a standard dilution plating was applied to coastal seawater samples collected from islands along the west coast of the Korean Peninsula, including Deokjeokdo, Baengnyeongdo, and Daebudo in 2022. A total of 2,007 bacterial strains were isolated from the samples as single colonies and identified using 16S rRNA gene sequence analyses. A total of 20 strains, with ≥98.7% 16S rRNA gene sequence similarity to bacterial species having validly published names but not reported in Korea, were designated as unrecorded bacterial species in Korea. The unrecorded bacterial strains were phylogenetically diverse and belonged to four phyla, five classes, 12 orders, 17 families, and 18 genera. The unreported species were assigned to Algimonas, Amylibacter, Notoacmeibacter, Roseibium, and Terasakiella of the class Alphaproteobacteria; Alteromonas, Congregibacter, Marinagarivorans, Marinicella, Oceanospirillum, Psychromonas, Thalassotalea, Umboniibacter, and Vibrio of the class Gammaproteobacteria; Lutibacter and Owenweeksia of the class Flavobacteriia; Paenibacillus of the class Bacilli; and Pelagicoccus of the class Opitutae. The taxonomic characteristics of the unreported species, including morphology, biochemistry, and phylogenetic position are provided in detail.
Three newly recorded rotifers were collected through surveys of several islands in Korea: Lecane perplexa (Ahlstrom, 1938); Lindia torulosa Dujardin, 1841; and Monommata maculata Harring & Myers, 1930. These species represent 24th, second, and third records of each genus discovered in Korea, respectively. Lecane perplexa and Monommata maculata, were collected from reservoirs using plankton nets, whereas Lindia torulosa was collected from a soil sample. The morphological characteristics of the discovered species are as follows: Lecane perplexa is characterized by a straight or slightly concave anterior margin of the lorica, an incomplete transverse fold on the ventral lorica, and a single toe with pseudoclaws and accessory claws; Lindia torulosa has an illoricated and vermiform body, a head with rostrum, a pair of auricles, cardate type trophi, and distinctively shaped epipharynx components; and Monommata maculata is characterized by long toes, an inner margin of rami with 10-12 serrated teeth, 3-4 large teeth, and interlocking teeth. Here, the morphological characteristics of the three Korean monogonont rotifers, which include trophi photographs, are presented. In addition, partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI) of each species are presented.
The region of the marine environment between shallow waters and deep-sea (30-150 m in depth) is referred to as the twilight or mesophotic zone. This zone has been scarcely examined, as these depths are too shallow for safe submersible operation. Since 2018, a survey of mesophotic echinoderms in Korea has yielded many specimens of interest. In this study, we present two newly recorded echinoderms, Henricia irregularis and Parastichopus nigripunctatus based on morphological redescriptions with high-definition photographs and DNA barcoding data for P. nigripunctatus.
We monitored the hitchhiker insect pests from the international vessels entering into Korea in 2021. As a result, total of 581 individuals were detected by the survey based on visual inspection with naked eye. Among them, 500 individuals were identified as 244 species of 65 families under 11 orders through the integrative taxonomic method with DNA barcoding and morphological reexamination, but the remaining 81 individuals were classified as only to the family level. Of the 244 species identified, 26 species were determined to be not-distributed species in Korea (two Orthoptera, two Hemiptera, one Megaloptera, five Coleoptera, three Hymenoptera, and 13 Lepidoptera). Among them, two species, Sagra femorata (Chrysomelidae, Coleoptera) and Dendrolimus punctatus (Lasiocampidae, Lepidoptera), were discovered as ‘Regulated species’ listed by Animal and Plant Quarantine Agency, South Korea. Therefore, we reported on the 26 not-distributed species in Korea and provided inanimate pathway information such as navigation routes on the vessels hitchhiking the species, state of the samples at the time of detection, identification results and original distribution for the detailed monitoring and the risk analysis on the species.