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Background: Culex tritaeniorhynchus, a major vector of Japanese encephalitis virus (JEV), is found across a broad geographical range, including Africa, Asia, Australia and Europe. Understanding the population structure and genetic diversity of pathogen vectors is increasingly seen as important for effective disease control. In China and Japan, two countries in close proximity to the Republic of Korea (ROK), Cx. tritaeniorhynchus has been categorized into two clades based on the DNA barcoding region of mitochondrial cytochrome c oxidase subunit I (COI), suggesting the presence of cryptic species. No comprehensive analysis of the genetic diversity in Cx. tritaeniorhynchus has been conducted in the ROK. To address this gap, we investigated the population structure of Cx. tritaeniorhynchus in the ROK. Methods: In Daegu, mosquito collections were conducted over a 2-year period from 2022 to 2023. For all other regions, Cx. tritaeniorhynchus specimens collected in 2023 were used. The COI barcoding region was analyzed to determine the genetic structure of the populations, supplemented with data from the 28S ribosomal DNA region. Each population was also examined for the eventual presence of Wolbachia infection. Finally, a back trajectory analysis was conducted to assess the possibility of international introduction of Cx. tritaeniorhynchus into the ROK. Results: The analysis of the COI region revealed the presence of two distinct clades within Cx. tritaeniorhynchus; these clades were the same as Cx. tritaeniorhynchus continental type (Ct-C) and C. tritaeniorhynchus Japanese type (Ct-J) previously reported. In contrast, the nuclear 28S region showed no significant genetic differentiation between these clades. Wolbachia infection was confirmed in some populations, but there was no evidence of an association with Wolbachia in Ct-C and Ct-J. It was also confirmed that the ROK is currently dominated by the Ct-J clade, with a possible introduction of Ct-C via air currents. Conclusions: Determining the presence of cryptic species is important for preventing vector-borne diseases. The results of this study confirm the existence of two clades of Cx. tritaeniorhynchus in the ROK, with Ct-J being the dominant clade. Our findings enhance current understanding of the genetic diversity within Cx. tritaeniorhynchus and provide valuable insights for the prevention of JEV outbreaks and the effective management of Cx. tritaeniorhynchus populations in East Asia. [ABSTRACT FROM AUTHOR]

Background: Thoracophelia Ehlers, 1897 is a genus of Opheliidae characterised by the body divided into three distinct regions, modified parapodia in chaetiger 10 and a ventral groove restricted to the posterior half of the body. To date, 18 species have been described in the genus. Amongst them, six species have been recorded in northeast Asia. New information: A new species, Thoracophelia foliformis sp. nov., was discovered in the intertidal zone of the Yellow Sea, South Korea. This is the first Thoracophelia species report from the Yellow Sea. This new species is closely related to T. dillonensis (Hartman, 1938) from California and T. ezoensis Okuda, 1936 from Japan in having pectinate branchiae. However, the new species can be distinguished from the two species by the unique combination of the following characteristics: 15 pairs of wrinkled pectinate branchiae with 12–15 filaments at best development and a foliaceous mid-ventral plate in the pygidium instead of one or two thick ventral cirri. Detailed descriptions and illustrations of T. foliformis sp. nov. are provided. Sequences of the mitochondrial cytochrome c oxidase subunit I (COI), nuclear 18S ribosomal DNA (rDNA) and 28S rDNA of the new species were determined and analysed. [ABSTRACT FROM AUTHOR]

Simple Summary: Honeybees (Apis mellifera) are crucial for our ecosystem, but they face various threats. This study investigates the detection of a new mite species emerging in Korean honeybees, Carpoglyphus lactis. Using the polymerase chain reaction method to amplify the Cytochrome c oxidase subunit 1 gene region, we examined the presence of C. lactis in honeybee colonies across nine provinces of the Republic of Korea. We found C. lactis in eight provinces in ROK, particularly during winter. This is the first identification of C. lactis in Korean honeybees. Identifying new threats is essential for beekeepers and researchers. Understanding the prevalence of C. lactis mite species and its impact on honeybee health will help develop strategies to protect bee populations. Apis mellifera, especially weak ones, are highly vulnerable to Carpoglyphus lactis mites, which can rapidly infest and consume stored pollen, leading to weakened colonies and potential colony collapse. This study aimed to ascertain and investigate the prevalence of this mite in honeybee colonies across nine provinces in the Republic of Korea (ROK). A total of 615 honeybee colony samples were collected from 66 apiaries during the spring and 58 apiaries during the summer of 2023. A 1242 bp segment of the Cytochrome c oxidase subunit 1 (COI) gene was amplified using the polymerase chain reaction method. The detection levels of C. lactis in the honeybees were compared between winter and summer. Based on the COI sequence analysis, the nucleotide sequence similarity of C. lactis mites isolated in the ROK with those from China (NC048990.1) was found to be 99.5%, and with those from the United Kingdom (KY922482.1) was 99.3%. This study is the first report of C. lactis in Korean apiaries. The findings of this study demonstrate a significantly higher detection rate in winter, which is 4.1 times greater than that in summer (p < 0.001). Furthermore, the results underscore the usefulness of molecular diagnostic techniques for detecting C. lactis mites. [ABSTRACT FROM AUTHOR]

Background: The genus Trioxys Haliday, 1833 consists of more than 80 species worldwide with three species being recorded in South Korea. In this study, we report the first observation of the two additional species, T. liui Chou & Chou, 1993 from Takecallis arundinariae (Essig, 1917) on Phyllostachys bambusoides Siebold & Zucc., 1843 and T. remaudierei Starý & Rakhshani, 2017 from T. taiwana (Takahashi, 1926) on Sasa borealis (Hack.) Makino & Shibata, 1901. New information: Trioxys liui and T. remaudierei are described and reported with phototographs of the diagnostic morphological characters and the mitochondrial cytochrome c oxidase subunit I (COI) data (barcode region) and Bayesian tree of the phylogenetic analysis amongst the closely-related taxa are provided. [ABSTRACT FROM AUTHOR]

A new feather mite species, Mycterialges boycianae sp. nov. (Xolalgidae), was identified from the Oriental Stork, Ciconia boyciana Swinhoe, 1873, in Korea. Males of M. boycianae sp. nov. are distinguished from Mycterialges mesomorphus Gaud & Atyeo, 1981, in having a single triangular prodorsal shield, sinuous margins of the opisthosoma located between setae e2 and h2 on the hysteronotal shield, an oval-shaped epiandrum without posterior extensions, a shorter tibia + tarsus IV than femoragenu IV, and an absent ambulacral disc of leg IV. Females differ in having a prodorsal shield with a posterior margin that is blunt-angular, and a concave posterior margin of the hysteronotal shield with posterior extensions. This study presents the first record of the feather mite genus Mycterialges in birds of the genus Ciconia (Ciconiidae). Additionally, we determined the phylogenetic relationship among Ingrassiinae using the mitochondrial cytochrome c oxidase subunit (COI). [ABSTRACT FROM AUTHOR]

Two members of the Culex pipiens subgroup, Culex pallens and Culex pipiens f. molestus, are known to occur in the Republic of Korea (ROK). These species exhibit morphologically similar features and are challenging to distinguish below the species level. Therefore, this study utilized wing geometric morphometrics (GM) on the right wing of the Culex pipiens subgroup, alongside sequencing of the cytochrome c oxidase subunit I (COI) region. Mosquitoes were collected from 11 locations between June and October (2020–2022) to minimize regional and seasonal variations. Additionally, Culex pipiens f. pipiens, which is not native to the ROK, was included in the analysis. Culex tritaeniorhynchus, Aedes albopictus, and Anopheles sinensis, the primary vectors in the ROK, were used as outgroups for comparison. All three taxa in the Culex pipiens subgroup could be identified with an 82.4%–97.0% accuracy using GM. However, a comparison of the COI regions of the Culex pipiens subgroup revealed no clear differences between the taxa. These data can be used for accurate identification, contributing to effective mosquito control, in addition to providing a foundation for evolutionary and ecological studies on wing shape differences. [ABSTRACT FROM AUTHOR]

Background: Malaria is still endemic in South Korea. However, limited information is available on the current Anopheles breeding sites and the occurrence of insecticide resistance-associated genetic mutations and their distribution needed to control the malaria vector efficiently. Methods: This study explored breeding sites of Anopheline adults in Gimpo-si, near the demilitarized zone (DMZ) in Gyeonggi-do province, South Korea, from 2022 to 2023. Genetic diversity was investigated based on the internal transcribed spacer (ITS2), cytochrome c oxidase subunit I (COI), and knockdown resistance (kdr) genes of Anopheles mosquitoes. A natural environment associated with the seasonal abundance of Anopheles larvae was characterized. Results: Two breeding sites of Anopheles larvae and adults were found at a stream margin or shallow freshwater near the forest in Wolgot-myeon in Gimpo-si without cattle shed within 1 km and in Naega-myeon in Ganghwa-gun with cow shed within 100 m in 2022 and 2023, respectively. Both sites were located between the newly cultivated lands and the forest. Besides, both breeding sites were in the valley at a slight elevation of 60–70 m from ground lands and maintained the shadow all day. Overall, the Wolgot-myeon breeding site showed various Anopheles spp. larvae, including Anopheles sinensis. Naega-myeon, an additional breeding site found in 2023, had Anopheles sineroides larvae, and approximately 59.7% (89/149) of An. sinensis adults inhabited within a 100-m distance. The total collection, including larvae and adults, revealed that An. sinensis, Anopheles pullus, Anopheles kleini, An. sineroides, Anopheles belenrae, and Anopheles lindesayi accounted for 44.2% (118/267), 0.7% (2/267), 0.7% (2/267), 22.1% (59/267), 1.9% (5/267), and 30.3% (81/267), respectively. Furthermore, various kdr mutant genotypes (F/F, C/C, L/F, L/C and F/C) in An. sinensis, and the first kdr allele mutant (L/F1014) in An. belenrae were identified in South Korea. Conclusions: Two breeding sites of Anopheles larvae were studied in Wolgot-myeon and Naega-myeon. Various Anopheles spp. larvae were detected in both habitats, but overall, An. sinensis was the most prevalent adults in both study sites. The occurrence of kdr allele mutant of An. belenrae in South Korea was reported. Rigorous larvae monitoring of Anopheles spp., continuously updating information on Anopheles breeding sites, and understanding the environmental conditions of Anopheles habitats are required to develop an effective malaria control programme in South Korea. [ABSTRACT FROM AUTHOR]

Patanga japonica Bolívar, 1898 (Orthoptera: Acrididae) is listed as a climate-sensitive indicator species in South Korea and is called southern group of insects in that the main distributional range is southern region of South Korea and Asian continent. In South Korea, thus, the species was distributed mainly in southern region of South Korea including southward a remote Jeju Island, but recently the species has often been detected in mid to northern region of South Korea, implying northward range expansion in response to climate change. Understanding the characteristics of the changes in genetic diversity during range expansion in response to climate change could be a foundation for the understanding of future biodiversity. Thus, in this study, we attempted to understand the changing pattern of the genetic diversity of the P. japonica in newly expanded regions. For the purpose of study, we collected 125 individuals from seven localities throughout South Korea including two newly distributed regions (Pyeongtaek and Yeongwol at ~37° N). These were sequenced for a segment of mitochondrial cytochrome oxidase subunit I (COI) and analyzed for genetic diversity, haplotype frequency, and population genetic structure among populations. Interestingly, northward range expansion accompanied only haplotypes, which are most abundant in the core populations, providing a significant reduction in haplotype diversity, compared to other populations. Moreover, genetic diversity was still lower in the expanded regions, but no genetic isolation was detected. These results suggest that further longer time would take to reach to the comparable genetic diversity of preexisting populations in the expanded regions. Probably, availability of qualified habitats at the newly expanded region could be pivotal for successful northward range expansion in response to climate change. [ABSTRACT FROM AUTHOR]

Reticulitermes speratus (Kolbe) is economically important pest in East Asia including Korea, Japan, and China where they infest wooden structures in urban areas. Previously, it has been reported that R. speratus consists of 5 subspecies, R. speratus kyushuensis Morimoto, R. speratus speratus Kolbe, R. speratus leptolabralis Morimoto, R. speratus okinawanus Morimoto, R. speratus yaeyamanus Morimoto, while only R. speratus kyushuensis was recorded in Korea in the past. However, it remains elusive if different subspecies of R. speratus other than R. speratus kyushuensis are present in Korea. In this study, we report the first record of R. speratus speratus from Korea, which was verified using soldier morphology and molecular characteristics obtained from a mitochondrial gene. R. speratus speratus Kolbe, 1885 (Blattodea: Rhinotermitidae) are found in several provinces, mainly southern regions in Korea, whereas R. speratus kyushuensis are distributed throughout the country. Our morphological comparison showed that R. speratus speratus can be distinguishable from R. speratus kyushuensis by the ratio of the posterior postmentum width to length. In the molecular comparison, R. speratus speratus revealed genetic differences of 3.06% (range 2.60–4.10%) from R. speratus kyushuensis using cytochrome oxidase subunit II gene sequences. [ABSTRACT FROM AUTHOR]

Ascidiella aspersa, originally native to the northeastern Atlantic, has emerged as a prolific invasive species in coastal waters worldwide. In 2010, it was identified as an alien species in Republic of Korea, rapidly colonizing artificial harbor structures and outcompeting native species. This study employs morphological analyses and genetic sequencing, focusing on mitochondrial DNA (cytochrome oxidase subunit I; mt-COI) and nuclear markers (18S rRNA), to unravel the genetic structure and haplotype diversity (Hd) of A. aspersa populations in Republic of Korea and globally. The analysis of 154 mt-COI and 127 18S rDNA global population sequences, as well as 80 mt-COI and 79 18S-rDNA Korean population sequences, revealed distinct genetic patterns. Among global populations, the mt-COI gene displayed significant genetic diversity, with 21 distinct haplotypes distributed across 41 polymorphic sites, which is indicative of extensive genetic variability. In contrast, the 18S rDNA marker exhibited limited diversity, with only four haplotypes identified at three polymorphic sites. In Korean populations, the mt-COI gene also exhibited substantial genetic diversity, with 14 distinct haplotypes displaying genetic variations at 29 polymorphic sites. Conversely, the 18S rDNA marker in Korean populations revealed a unique genetic pattern, with only one shared haplotype. These findings emphasize the complex genetic diversity within A. aspersa populations, both globally and in Republic of Korea. This genetic analysis provides valuable insights into the species' colonization history and adaptation mechanisms, shedding light on the factors shaping its genetic structure. Further research is warranted to elucidate the ecological implications of these genetic patterns in the context of invasion biology. [ABSTRACT FROM AUTHOR]

Recent molecular approaches toward insect taxonomy are revealing cryptic diversity within biting midge genus Culicoides Latreille, 1809. A new biting midge species was collected from highly restricted area of Dokdo Island, East Sea of the Republic of Korea, and was identified as Culicoides dokdoensis, sp. nov., based on morphological characters and DNA barcoding. The specimens collected from the island were previously known as Culicoides circumscriptus Kieffer, 1918, a cosmopolitan blood‐feeder, due to its morphological similarity. However, the specimens from Dokdo Island can be distinguished from other congeners by the following characters: more curved arms in male aedeagus, wing spot pattern, sensory pit depth, and absence of a spermatheca neck in female. In addition, mitochondrial cytochrome c oxidase I sequence exhibited substantial genetic difference compared to C. circumscriptus populations from the Korean Peninsula, sufficiently supporting the genetic differentiation between the two species. The discovery of this cryptic species highlights the necessity of integrated taxonomy for Culicoides. [ABSTRACT FROM AUTHOR]

Phytophthora species, classified under Oomycota, cause significant damage to various crops and trees. The present study introduced Phytophthora species, P. nagaii and P. tentaculata, new to Korea, which pose notable risks to their respective host plants. Our research provided a comprehensive description of these species taking into account their cultural features, morphological characteristics, and molecular phylogenetic analysis using the internal transcribed spacer rDNA region and cytochrome c oxidase subunit mtDNA genes (cox1 and cox2) sequences. In addition, this study first evaluated the sensitivity of P. nagaii and P. tentaculata to five anti-oomycete fungicides, finding both species most responsive to picarbutrazox and P. tentaculata resistant to fluazinam. The data can guide targeted treatment strategies and offer insights into effective control methods. The findings expand our understanding of the diversity, distribution, and management of Phytophthora species in Korea. [ABSTRACT FROM AUTHOR]

The present study performed an in-depth investigation of rust diseases affecting Meliosma myriantha and Meliosma oldhamii trees (Sabiaceae) in Korea. The analysis identified four distinct species of the genus Neophysopella (Pucciniales) as the causal agents. Among these, N. hornotina was found to infect only M. oldhamii, whereas three Neophysopella species (N. meliosmae, N. meliosmae-myrianthae, and N. vitis) were parasitic on M. myriantha. To our knowledge, this is the first report of the former two species (N. hornotina and N. meliosmae) in Korea. In addition, we specified their alternate host plants for two heteroecious species (N. meliosmae-myrianthae and N. vitis) in Korea, completing the life cycles of the four rust species, and provided detailed morphological descriptions at each stage of their life cycles. Phylogenetic relationships of these rust species were uncovered using a comprehensive sample size, and we have constructed a phylogenetic tree for Neophysopella using the cytochrome c oxidase subunit III (cox3) gene sequences, demonstrating an effective approach for species delineation within this genus. The findings contribute to identifying and managing rust diseases affecting Meliosma species. [ABSTRACT FROM AUTHOR]

Cryptic diversity refers to two or more distinct species classified as a single species due to lack of morphological difference. Although Plocamium Lamouroux has potential applications in biotechnology, several phylogenetic studies suggest the presence of cryptic diversity within the genus that requires further phylogenetic evaluation. Here, we investigated two species of Plocamium, P. "cartilagineum" and P. "telfairiae", in the Northwest (NW) Pacific. The aims of this study are to identify potential cryptic species by analyzing the genetic differences between the species from their type localities and specimens from the NW Pacific, to characterize their population genetic diversity and structure, and to find potential hotspots with high intraspecific genetic diversity in Korea. A reconstructed phylogenetic tree based on mitochondrial 5' region of cytochrome c oxidase subunit I (COI-5P) and plastid ribulose-1,5-bisphosphate carboxylase / oxygenase large subunit (rbcL) with molecular delimitation methods revealed significant differences as distinct species in the genus Plocamium. Comparison with specimens from their type localities indicated the presence of two cryptic species in the NW Pacific, including Plocamium luculentum sp. nov. The phylogeographic study for both species showed low genetic differences among populations, demonstrating genetic connectivity within the NW Pacific. These findings could promote the discovery of other morphologically and ecologically similar but phylogenetically different Plocamium species worldwide, which is essential for conservation assessments. [ABSTRACT FROM AUTHOR]

The crustose brown algal family Ralfsiaceae comprises four genera: Analipus, Endoplura, Heteroralfsia, and Ralfsia. This study provides a detailed description of Fissipedicella orientalis gen. et sp. nov. based on molecular and morphological analyses. Our phylogenetic analyses from rbcL and concatenated dataset (rbcL + 5' region of cytochrome c oxidase subunit I [COI-5P]) reveal that specimens collected in Korea are nested in a distinct new clade within Ralfsiaceae with robust bootstrap support and Bayesian posterior probabilities. The sequence divergences for rbcL and COI-5P between F. orientalis and other genera within Ralfsiaceae are 7.4-10.1 and 17.5-21.2%, respectively. Fissipedicella orientalis is characterized by crustose thalli with a hypothallial basal layer and erect perithallial filaments, tufts of hairs in pits, a single chloroplast per cell, plurangia with 1-3 sterile cells, and unangia on stalks composed of 1-6 vertically or obliquely cleaved cells. We propose that F. orientalis can be recognized as a new genus-level taxon within Ralfsiaceae, even though a single species represents it. Our new genus, Fissipedicella, is distinguished from the other members within the Ralfsiaceae by the type of thallus, the number of chloroplasts and tufts of hairs in pits, and the development of unangia. [ABSTRACT FROM AUTHOR]

Some aphid species form close associations with ants: offering them honeydew and obtaining protection from ants in return. However, mutualistic interactions with ants can also have a negative influence on aphid physiological and morphological traits. Wolbachia are intracellular bacteria whose major genotypes are classified into 17 supergroups (A to S except G and R). Aphid species within the genus Tuberculatus feed on Fagaceae leaves and exhibit two contrasting ecological characteristics, ant-attendance and non-attendance. Previous work has found that ant-attended species exhibit lower dispersal and are likely to form aggregated colonies. Considering that host-parasitoid interactions may well be one of the most common horizontal transmission routes of Wolbachia, it is therefore expected that ant associations will be associated with higher Wolbachia infection rate in Tuberculatus aphid species. This study compared Wolbachia infection rates between 11 ant-attended and 12 non-attended Tuberculatus aphid species, which were collected throughout Japan and around Mt. Kariwangsan in South Korea. Mean infection rates of Wolbachia were 30.2% in ant-attended species and 3.1% in non-attended species. The Wolbachia haplotypes detected were classified into supergroups B, M, N, and O. A phylogenetic tree of Tuberculatus aphids constructed from a mitochondrial gene of cytochrome oxidase subunit I and nuclear gene of 18S rRNA was used to examine the correlation between Wolbachia infection rates and ant associations. The phylogenetic comparative analysis showed that Wolbachia infection rates were significantly higher in ant-attended species. Possible Wolbachia infection routes are discussed in terms of the differences in the ecological characteristics between ant-attended and non-attended aphid species. This study shows that the spread of microorganisms is affected by host species interactions, and contributes new insights into the evolution of mutualistic interactions. [ABSTRACT FROM AUTHOR]

The genus Hexatoma Latreille, 1809 is a large group of aquatic crane flies, with almost 600 species worldwide. The largest subgenus is Eriocera Macquart, 1838, which includes all nine species known from the Korean Peninsula. Molecular methods were used to associate Hexatoma larvae with their putative adult species from South Korea. Mitochondrial Cytochrome c Oxidase Subunit I (COI) gene fragment sequences (DNA barcodes) of recently collected adults of H. (E.) gifuensis, H. (E.) ilwola, H. (E.) pernigrina, and H. (E.) pianigra were compared with twelve sequences of Hexatoma larvae. The larvae of H. (E.) pernigrina, H. (E.) pianigra, and H. (E.) gifuensis were associated with their putative adults. The larvae of H. (E.) gifuensis and H. (E.) pianigra and the larvae and pupae of H. (E.) pernigrina are described and illustrated. The larvae of two species not associated with any adult are described, and their COI gene fragment sequences (DNA barcodes) are presented. This paper presents the morphological characteristics suitable for distinguishing larval species. A key for the identification of larvae of the genus Hexatoma on the Korean Peninsula has been compiled. H (E.) sachalinensis is recorded from the Korean Peninsula for the first time. Our study is the first contribution to the Hexatoma larvae taxonomy using phylogenetic analysis based on mitochondrial COI fragment (DNA barcode) and one of the first attempts to reveal phylogenetic relationships between Hexatoma species using molecular markers. [ABSTRACT FROM AUTHOR]

Severe root rot was observed in onion seedlings growing in nursery seedbeds in Changnyeong, South Korea in September 2021. The diseased onion seedlings showed symptoms including water-soaking, browning and blight, followed by seedling collapse. Three isolates were obtained from diseased onion seedlings, and their morphological characteristics were found to be similar to previously described Pythium species. Artificial inoculation with isolates produced identical symptoms to those observed in the original infection. Based on morphological characteristics, sequencing of rRNA gene internal transcribed spacer, ribosomal large subunit gene region, and cytochrome c oxidase subunit I gene region, and pathogenicity testing, the causative agent of root rot on the onion seedlings was identified as Globisporangium irregulare (formerly Pythium irregulare). This is the first report of root rot caused by G. irregulare on onion seedlings in Korea. The results of this study suggest that root rot may pose a severe threat to onion seedling cultivation. [ABSTRACT FROM AUTHOR]

Due to the close relationship between pets and humans, pet owners are highly invested in proper diets for their pets. Even though pet food mislabeling is concerning, there are few studies on this topic. This study investigated pet food mislabeling in South Korea's market based on DNA barcoding. In total, 10 pet food products were purchased, and 200 sequences of the partial Cytochrome c oxidase subunit 1 (COI) gene were generated from clones of the samples. The obtained sequences were compared to available public databases to identify species present in the ingredients. The data analyses showed that the labeled species were consistent with species detected by COI sequences in 6 of the products. However, the expected species were not detected in 4 products, revealing possible mislabeling in these samples. Our findings indicated that DNA barcoding might represent a promising tool to detect pet food mislabeling. [ABSTRACT FROM AUTHOR]

A new species, Robertgurneya jejuensis sp. nov., was described from sandy sediment samples collected at a depth of 25 m on Mun Island, Jeju, in June 2018. The new species is morphologically similar to Robertgurneya similis similis (Scott A., 1896) and Robertgurneya donghaensis Bang, 2021; this is the second record of the genus Robertgurneya in South Korea. The morphological characteristics of the similis group within the genus Robertgurneya, to which the new species is ascribed, are summarized here. Furthermore, an identification key is provided based on the summary. Molecular identification of the collected specimens, based on the nuclear 18S ribosomal RNA (18S rRNA) and the mitochondrial cytochrome oxidase subunit I fragment, was obtained. Finally, a phylogenetic tree was constructed to present the position of Robertgurneya within the Miraciidae family based on 18S rRNA sequences which is relatively conserved. As a result, the relationship with sister genera morphologically similar to Robertgurneya was also molecularly confirmed. [ABSTRACT FROM AUTHOR]

House dust mites (HDMs) including Dermatophagoides spp. are an important cause of respiratory allergies. However, their relationship with microorganisms in house dust has not been fully elucidated. Here, we characterized bacteria and fungi associated with HDMs in house dust samples collected in 107 homes in Korea by using DNA barcode sequencing of bacterial 16S rRNA gene, fungal internal transcribed spacer 2 (ITS2) region, and arthropod cytochrome c oxidase I (COI) gene. Our inter-kingdom co-occurrence network analysis and/or indicator species analysis identified that HDMs were positively related with a xerophilic fungus Wallemia, mycoparasitic fungi such as Cystobasidium, and some human skin-related bacterial and fungal genera, and they were negatively related with the hygrophilous fungus Cephalotrichum. Overall, our study has succeeded in adding novel insights into HDM-related bacteria and fungi in the house dust ecosystem, and in confirming the historically recognized fact that HDMs are associated with xerophilic fungi such as Wallemia. Understanding the microbial ecology in house dust is thought to be important for elucidating the etiology of human diseases including allergies, and our study revealed baseline information of house dust ecology in relation to HDMs. The findings could be useful from a perspective of human health. [ABSTRACT FROM AUTHOR]

Ascidians are sessile marine invertebrates and many are invasive. One notorious example is the solitary species Microcosmus squamiger, which has spread from a hypothesized native region in southeastern Australia to temperate waters worldwide and is considered a global marine invader. This study is the first report of M. squamiger from Jeju Island, South Korea. We collected specimens (N = 20) from Unjin and Wimi harbors on Jeju Island and dissected them to characterise their siphons, pharynx, and dorsal tubercle using stereomicroscopy and scanning electron microscopy. The shape of the dorsal tubercle (the peritubercular area filled with two spiral coils) and the length (15-20 µm) and shape (roof tile or fingernail) of the siphon spine were consistent with previous identifications of the species. Additionally, molecular verification was performed by extracting genomic DNA from four specimens, two each from Unjin and Wimi harbors. By sequencing a section of the mitochondrial cytochrome oxidase subunit I gene and analysing the generated sequences using a maximum likelihood-based phylogenetic tree, we compared to individuals previously identified as M. squamiger and confirmed the existence of two clades. Therefore, the presence of M. squamiger was verified by morphological and phylogenetic identification. Although M. squamiger is currently distributed globally (except in Antarctica), records from India (2006), Okinawa, and Japan (2007 and 2014) suggest that it was introduced into Asia in the last decade. Though no economic or biological damage caused by this species has been reported in South Korea, the high density of M. squamiger (50-60 individuals/rope-meter) is a potential hazard to other native species via fouling and competition for food and space. Therefore, further research is needed to determine the possible vectors and to continue to monitor its possible spread. [ABSTRACT FROM AUTHOR]

The chigger mite is a known vector for the zoonotic disease, Tsutsugamushi, which affects more than 4,000 patients each year in the Republic of Korea (ROK) since 2004. However, molecular data is only available for a few species of chigger mite, compared to the numbers of known species. This study focused on securing molecular data for six species (Leptotrombidium pallidum, Leptotrombidium scutellare, Leptotrombidium palpale, Leptotrombidium orientale, Neotrombicula gardellai, and Euschoengastia koreaensis) of chigger mites in the ROK from cytochrome c oxidase subunit I (COI) and internal transcribed spacer 2 (ITS2). In the results, there were each two genotypes in L. pallidum and L. palpale, and three genotypes in L. scutellae in the COI, whereas the ITS2 sequence was identical within the species. The other three species were identical from COI and ITS2. This study first revealed the genetic variation in the COI sequences of chigger mites in the ROK. Further studies could determine how this variation is related to ecological behavior and disease transmission. [ABSTRACT FROM AUTHOR]

The ivory barnacle Amphibalanus eburneus is a marine crustacean, which presents near-cosmopolitan distribution due to extensive introduction and exhibits a wide spectrum of phenotypic variation. To elucidate geographical differentiation among populations through invasion, we investigated variation in genetic structure, shell morphology, and recruitment pattern for A. eburneus, from the southern Korean Peninsula where it has been established since the late 1980s. We selected samples from four populations in corresponding ecologically-relevant regions representing all surrounding South Korean waters. From these we amplified the mitochondrial genetic marker cytochrome oxidase subunit I (COI) from 57 individuals and performed a populational genetic analyses with 11 additional GenBank sequences to evaluate population structure. To examine morphological variation, we applied two-dimensional landmark-based geometric morphometrics to the scutum and tergum for 148 and 151 individuals, respectively. Furthermore, we estimated the density of year-old individuals in the field to compare recruitment responses among localities. We detected 33 haplotypes among the four locations belonging to three distinct clades based on moderate intraspecific pairwise genetic distance (=3.5%). The haplotypes in these clades were not locality-specific in their distribution. In contrast, we did detect interpopulation variation in opercular shape and morphospace structure, and one population could be separated from the rest based on its distinct tergum morphotype alone. This morphologically distinct population was also differentiated by displaying the lowest mean recruitment density. Our results indicate that although there is no relationship between molecular variation in the COI gene and geographic regions in South Korea, association with locality for operculum morphology, and recruitment response suggest ecological adaptation by this barnacle in a new habitat. [ABSTRACT FROM AUTHOR]

The genus Toxares Haliday, 1840 is a small taxon of Aphidiinae, consisting four valid species in the world. One Toxares species is recorded as new to science from South Korea, in this study. Descriptions and illustrations of the new species, T. koreanus sp. nov., are provided, together with their mitochondrial cytochrome c oxidase subunit I (COI) and D2 region of the nuclear gene for 28S rRNA (28S) sequences. The phylogenetic tree reconstructed using a combination of COI and 28S revealed the phylogenetic position of the genus Toxares within Aphidiinae. [ABSTRACT FROM AUTHOR]

Two new species of the genus Cratospila Foerster, 1863 (Braconidae: Alysiinae), Cratospila albosignata sp. nov. and C. longivena sp. nov., are described and illustrated. In addition, the DNA barcode region of the mitochondrial cytochrome c oxidase subunit I (COI) of both species has been sequenced with three previously described species (C. albifera, C. luteocephala and C. syntoma). Alysia ponerola Papp, 2009 which was recorded from North Korea is transfered in Cratospila (C. ponerola (Papp, 2009) comb. nov.). All species validly recorded from Korea are included in a revised key. [ABSTRACT FROM AUTHOR]

A new species of freshwater gammarid, Gammarus somaemulensis sp. nov., was collected from Somaemuldo Island, South Korea. This new species is morphologically characterised by the absence of calceoli in antenna 2, absence of anteroproximal setae on bases in pereopods 6 and 7, outer ramus in uropod 3 with plumose setae on both margins, and a small terminal article of the outer ramus, which is shorter than adjacent spines. A description of the new species and morphological differences from related species are provided in the text. The new species was also compared to related species using partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene. Genetic distances of COI sequences between the new species and related species, consisting of 21.5-26.3% difference, support Gammarus somaemulensis sp. nov. as a valid species. Additionally, a key to identifying Gammarus species in South Korea is provided. [ABSTRACT FROM AUTHOR]

Purpose: Metagonimiasis, commonly seen in East Asian countries, is a parasitic disorder caused by definitive hosts' ingestion of undercooked freshwater fishes. Recently, genetic analysis has proved 28S rRNA and cytochrome c oxidase subunit I (COI) mtDNA gene to be a successful marker differentiating species of the genus Metagonimus. In the present study, using specimens from the newly discovered Joseon Dynasty human remains of Goryeong, we obtained updated genetic data on genus Metagonimus, which was also prevalent during the Joseon period. Methods: The ancient DNA (aDNA) was retrieved from the coprolite sample of the seventeenth century, half-mummified individual discovered at Goryeong Country, South Korea. Cloning and sequencing were performed on PCR-amplified amplicons for M. yokogawai 28S rRNA and COI mtDNA gene. The consensus sequences were used for species identification and phylogenetic analysis using NCBI/BLAST and MEGA X software. Results: Based on the COI mtDNA gene region, the Goryeong sequence was confirmed as belonging to M. yokogawai, as it was shown to form a separate cluster with other M. yokogawai taxa that are distinct also from M. takahashii and M. miyatai. Conclusion: In a series of our genetic analyses on genus Metagonimus using samples retrieved from Joseon-period cases, aDNA sequences of genus Metagonimus revealed in South Korea thus far are those of M. yokogawai, but not of M. miyatai or M. takahashii yet. [ABSTRACT FROM AUTHOR]

Ellobium chinense is a red-listed snail species of the family Ellobiidae with a geographic distribution from Vietnam and south coast of China to South Korea and mainland Japan. This species is restricted to specialized habitats in a narrow upper-intertidal to lower-supratidal zone of salt marshes and thus particularly sensitive to environmental degradation through land reclamation and other human activities. Here, we first report the genetic diversity and population structure of E. chinense in Japan to evaluate the connectivity and conservation value of its local populations. Specimens were collected from seven localities (Tsu, Okayama, Yamaguchi, Usa, Imari, Saga and Izumi) that cover the species' present distribution in the country. Analyses of 612-bp sequences of the mitochondrial cytochrome c oxidase subunit I gene showed high genetic diversity within populations and a reasonable level of connectivity among populations. However, significant genetic differentiation was detected among distant geographic regions in Japan and South Korea, due potentially to the disjunct distribution of habitable salt marshes and a short pelagic larval period of the species. The population of the Ise-Mikawa Bay area, representing the eastern limit of the current distribution range, showed the highest level of genetic differentiation and deserve particular conservation efforts to avoid local extinction, which occurred in Tokyo Bay area in the last century. [ABSTRACT FROM AUTHOR]

To date, 19 species of spiny lobsters from the genus Panulirus have been discovered, of which only P. japonicus, P. penicilatus, P. stimpsoni, and P. versicolor have been documented in South Korean waters. In this study, we aimed to identify and update the current list of spiny lobster species that inhabit South Korean waters based on the morphological features and the phylogenetic profile of cytochrome oxidase I (COI) of mitochondrial DNA (mtDNA). Spiny lobsters were collected from the southern and eastern coasts of Jeju Island, South Korea. Phylogenetic analyses were performed using neighbor-joining (NJ), maximum likelihood (ML), and Bayesian inference (BI) methods. The ML tree was used to determine the spiny lobster lineages, thereby clustering the 17 specimens collected in this study into clades A, B, C, and D, which were reciprocally monophyletic with P. japonicus, P. homarus homarus, P. longipes, and P. stimpsoni, respectively. These clades were also supported by morphological examinations. Interestingly, morphological variations, including the connected pleural and transverse groove at the third abdominal somite, were observed in four specimens that were genetically confirmed as P. japonicus. This finding is novel within the P. japonicus taxonomical reports. Additionally, this study updates the documentation of spiny lobsters inhabiting South Korean waters as P. longipes and P. homarus homarus were recorded for the first time in this region. [ABSTRACT FROM AUTHOR]

Although Clonorchis sinensis is a parasite that still infects many people in East Asia, its genetics remain largely unknown. We conducted ancient DNA analysis of C. sinensis eggs obtained from a Joseon period mummy newly discovered in South Korea. Clonorchis sinensis DNA was amplified for internal transcribed spacer 1, cytochrome c oxidase subunit 1, and NADH dehydrogenase subunit 2 and 5 genes. The results of BLAST/NCBI showed that the consensus sequences were 98.24 to 100% identical to the modern and ancient C. sinensis sequences reported from Korea, China, Japan, and other Asian countries. Our report helps to fill in the genetic profile of ancient C. sinensis strains that infected East Asian people hundreds of years ago. [ABSTRACT FROM AUTHOR]

The species of the genus Hylcalosia Fischer, 1967 (Braconidae: Alysiinae) from South Korea are revised. One species, Hylcalosia bicolor sp. nov., is new to science. They are described and illustrated herein and an identification key to the Korean species is added. In addition, the DNA barcode region of the mitochondrial cytochrome c oxidase subunit I (COI) has been analysed for the new species and H. sutchanica is used for genetic comparison. [ABSTRACT FROM AUTHOR]

The species of the genus Phaenocarpa Foerster, 1863 (Braconidae: Alysiinae) from South Korea are revised, and the genus is recorded for the first time from South Korea. Three species, Phaenocarpa artotemporalis sp. nov., P. brachyura sp. nov. and P. lobata sp. nov., are new to Science, and two species, P. masha Belokobylskij, 1998 and P. fidelis Fischer, 1970, are newly recognized in South Korea. They are described and illustrated herein with a provision of the identification key to the Korean species. In addition, the DNA barcode region of the mitochondrial cytochrome c oxidase subunit I (COI) has been analyzed for the six species including P. ruficeps for genetic comparison. [ABSTRACT FROM AUTHOR]

Several species of the genus Aphidius are well known as commercial biocontrol agents of pest aphids, and more than 130 species of the genus have been recorded worldwide. To date, only 15 Aphidius species have been recorded in South Korea. Using the DNA barcode region (ca. 658 bp) of mitochondrial cytochrome c oxidase subunit I (COI), we amplified sequences of 15 Aphidius Korean species, aligned them in combination with 23 reference species retrieved from GenBank for comparison and identification, and then reconstructed a barcode phylogeny by the neighbour-joining method. As a result, three Aphidius species were found to be new to Science. Descriptions and illustrations of the three species new to Science -- Aphidius longicarpus sp. nov., A. longistigmus sp. nov., and A. asiaticus sp. nov. -- are provided, together with their phylogenetic position within the genus Aphidius. In addition, a redescription of A. areolatus, a parasitoid of maple aphids (Peryphillus spp.), is also given. [ABSTRACT FROM AUTHOR]

Background: Bats are hosts for many ectoparasites and act as reservoirs for several infectious agents, some of which exhibit zoonotic potential. Here, species of bats and bat flies were identified and screened for microorganisms that could be mediated by bat flies. Methods: Bat species were identified on the basis of their morphological characteristics. Bat flies associated with bat species were initially morphologically identified and further identified at the genus level by analyzing the cytochrome c oxidase subunit I gene. Different vector-borne pathogens and endosymbionts were screened using PCR to assess all possible relationships among bats, parasitic bat flies, and their associated organisms. Results: Seventy-four bat flies were collected from 198 bats; 66 of these belonged to Nycteribiidae and eight to Streblidae families. All Streblidae bat flies were hosted by Rhinolophus ferrumequinum, known as the most common Korean bat. Among the 74 tested bat flies, PCR and nucleotide sequencing data showed that 35 (47.3%) and 20 (27.0%) carried Wolbachia and Bartonella bacteria, respectively, whereas tests for Anaplasma, Borrelia, Hepatozoon, Babesia, Theileria, and Coxiella were negative. Phylogenetic analysis revealed that Wolbachia endosymbionts belonged to two different supergroups, A and F. One sequence of Bartonella was identical to that of Bartonella isolated from Taiwanese bats. Conclusions: The vectorial role of bat flies should be checked by testing the same pathogen and bacterial organisms by collecting blood from host bats. This study is of great interest in the fields of disease ecology and public health owing to the bats' potential to transmit pathogens to humans and/or livestock. [ABSTRACT FROM AUTHOR]

Background: Plasmodium vivax is transmitted by members of the Anopheles Hyrcanus Group that includes six species in the Republic of Korea: Anopheles sinensis sensu stricto (s.s.), Anopheles pullus, Anopheles kleini, Anopheles belenrae, Anopheles lesteri, and Anopheles sineroides. Individual Anopheles species within the Hyrcanus Group demonstrate differences in their geographical distributions, vector competence and insecticide resistance, making it crucial for accurate species identification. Conventional species identification conducted using individual genotyping (or barcoding) based on species-specific molecular markers requires extensive time commitment and financial resources. Results: A population-based quantitative sequencing (QS) protocol developed in this study provided a rapid estimate of species composition ratios among pooled mosquitoes as a cost-effective alternative to individual genotyping. This can be accomplished by using species- or group-specific nucleotide sequences of the mitochondrial cytochrome C oxidase subunit I (COI) and the ribosomal RNA internal transcribed spacer 2 (ITS2) region as species identification alleles in a two-step prediction protocol. Standard genomic DNA fragments of COI and ITS2 genes were amplified from each Anopheles species using group-specific universal primer sets. Following sequencing of the COI or ITS2 amplicons generated from sets of standard DNA mixtures, equations were generated via linear regression to predict species-specific nucleotide sequence frequencies at different positions. Species composition ratios between An. sineroides, An. pullus and An. lesteri were estimated from QS of the COI amplicons based on the mC.260A, mC.122C and mC.525C alleles at the first step, followed by the prediction of species composition ratios between An. sinensis, An. kleini and An. belenrae based on QS of the ITS2 amplicons using the rI.370G and rI.389T alleles. The COI copy number was not significantly different between species, suggesting the reliability of COI-based prediction. In contrast, ITS2 showed a slightly but significantly higher copy number in An. belenrae, requiring an adjustment of its predicted composition ratio. A blind test proved that predicted species composition ratios either from pooled DNA specimens or pooled mosquito specimens were not statistically different from the actual values, demonstrating that the QS-based prediction is accurate and reliable. Conclusions: This two-step prediction protocol will facilitate rapid estimation of the species composition ratios in field-collected Anopheles Hyrcanus Group populations and is particularly useful for studying the vector ecology of Anopheles population and epidemiology of malaria. [ABSTRACT FROM AUTHOR]

Piophilidae are a relatively small family of Diptera that is frequently associated with cadavers at advanced stages of decomposition and are, therefore, considered potentially useful forensic indicators. However, their use in forensic investigations is typically hampered by a deficiency in reliable identification tools. This is particularly evident in countries such as South Korea, where forensic entomology is still in its infancy and the diversity of forensically relevant insect taxa remains largely undocumented. In the present study, we used cytochrome c oxidase subunit I (COI) barcodes to identify samples of piophilid larvae collected during medicolegal investigations performed in South Korea. A total of 174 COI sequences were obtained and have been made publicly available, thus augmenting the reference barcode library for forensically important Piophilidae species. Of the 174 sequenced samples, 172 were identified as Stearibianigriceps (Meigen), whereas the two remaining samples may represent a previously unsequenced piophilid species. Stearibianigriceps is recorded from South Korea for the first time, and our results suggest that it might be a particularly relevant forensic indicator in certain case types and scenarios in that country. The findings of this study highlight the utility of COI barcodes for achieving accurate identification of entomological samples, even by non‐specialist forensic practitioners. They also contribute to the further development and consolidation of forensic entomology in South Korea and eastern Asia. [ABSTRACT FROM AUTHOR]

A new parabathynellid bathynellacean species, Hangangbathynella mihoensis sp. nov., was found in the groundwater of the Geumgang River in South Korea. This is the first report of Hangangbathynella from a tributary of the Geumgang River. All previously-reported species were found in the Hangang River and the origins of the two rivers are distinct from each other. The new species can be distinguished from its congeners by the two-segmented mandibular palp and the absence of epipods on thoracopod II. In this study, we provide a description of the new species and an identification table for the genus Hangangbathynella. In addition, we obtained partial sequences of the mitochondrial cytochrome c oxidase subunit I gene for DNA barcoding. [ABSTRACT FROM AUTHOR]

The present-day genetic structure of macroalgal species reflects both geographical history and oceanic circulation patterns as well as anthropogenic introduction across native ranges. To precisely understand the genetic diversity and how the factors shape the current population structure of Gloiopeltis furcata sensu lato, we determined the mitochondrial 5' end of cytochrome c oxidase subunit I (COI-5P) sequences for 677 individuals sampled from 67 sites spanning almost the entire distribution range in Korea and Japan. Results from the phylogenetic analysis and haplotype distribution revealed eleven distinct lineages within G. furcata s.l. along the Korea-Japan coastal areas and displayed divergent phylogeographic patterns among lineages. Despite the closely related lineages distributed in same habitats as high rocky intertidal zone, they display different phylogeographic patterns among lineages. The populations from the south of Korea-Japan harbored the highest genetic diversity and unique endemism in comparison with other populations in the distribution range. This could be the evidence of southern refugia for G. furcata s.l. in the Northwest (NW) Pacific and the recent migration from native to introduced region. The reason is that an exceptional distribution pattern was found high genetic diversity in Hakodate of Japan where is the northern location in the NW Pacific. Our results imply the contemporary influence on the distribution due to current circulation pattern and anthropogenic effects. These phylogeographic findings provide the important insight into cryptic species diversity and the detailed distribution pattern of Gloiopeltis in the NW Pacific. [ABSTRACT FROM AUTHOR]

Scincella vandenburghi is a small lygosomine skink, distributed in Tsushima Island and the Korean Peninsula as well as their adjacent islands. We analyzed the within-species genetic variation among the populations of Tsushima Island, Cheju Island, and the Korean Peninsula using partial sequences of mitochondrial DNA, cytochrome b and cytochrome c oxidase subunit I genes. We detected 20 haplotypes in total. Little genetic divergence was observed among the populations of S. vandenburghi from the Korean Peninsula, Tsushima Island, and Cheju Island. Genetic diversity was low in this species and demographic statistics suggested the recent expansion of distribution. Considering that Tsushima Island has been separated from the Korean Peninsula since 0.43 million years ago and that a narrow seaway had persisted between these two areas even during the Last Glacial Maximum, the low genetic divergence in S. vandenburghi suggests that this species expanded its range from the Korean Peninsula to Tsushima Island by oversea dispersal. [ABSTRACT FROM AUTHOR]

Microcotyle sebastis is a gill monogenean ectoparasite that causes serious problems in the mariculture of the Korean rockfish, Sebastes schlegelii. In this study, we isolated the parasite from fish farms along the coasts of Tongyeong, South Korea in 2016, and characterized its infection, morphology and molecular phylogeny. The prevalence of M. sebastis infection during the study period ranged from 46.7% to 96.7%, and the mean intensity was 2.3 to 31.4 ind./fish, indicating that the fish was constantly exposed to parasitic infections throughout the year. Morphological observations under light and scanning electron microscopes of the M. sebastis isolates in this study showed the typical characteristics of the anterior prohaptor and posterior opisthaptor of monogenean parasites. In phylogenetic trees reconstructed using the nuclear 28S ribosomal RNA gene and the mitochondrial cytochrome c oxidase I gene (cox1), they consistently clustered together with their congeneric species, and showed the closest phylogenetic relationships to M. caudata and M. kasago in the cox1 tree. [ABSTRACT FROM AUTHOR]

To generate information on variability in the pathogen causing white rust disease in Brassica species and their ability to infect Brassica juncea genotypes, thirteen isolates of Albugo candida infecting B. juncea and one isolate of Wilsonia bliti infecting Amaranthus blitum were collected from different rapeseed-mustard growing regions of India. These isolates were characterized based on different morphological data (sporangial shape and size; shape, size, and color of the pustule) and molecular data (cytochrome c oxidase subunit II (COX2) of mtDNA and internal transcribed spacer (ITS) region of rDNA). All the sporangia were globose or spherical to ellipsoidal with a size ranging from 199.01 μm2 to 357.23 μm2. White to creamy colored pustules were observed with a diameter ranging from 0.5–3.0 mm. Sequence analysis revealed that the Indian isolates of A. candida collected from B. juncea showed close identity with the Korean isolates infecting B. juncea. W. blilti isolate collected from A. blitum form a distinct clade with A. amaranthi infecting Amaranthus spinosus from Korea. Further, the pathogenic reaction of ten A. candida isolates was recorded on thirty genotypes of B. juncea that exhibited differential responses to the tested isolates. The three genotypes, PDZ-3, Pusa Karishma, and Donskaja were found to be resistant against all the ten isolates, which can further be used as a resistance source. PDZ-2 genotype was found to be susceptible only against the Ac-Hr isolate while the genotype BioYSR shows a susceptible reaction against Ac-Skn and Ac-Wltn isolates only. This set of thirty genotypes was able to differentiate the ten isolates of A. candida into four physiological races (AcRBj1 to AcRBj4) based on the disease reaction. The information generated through this study will be helpful for further study on identification and molecular mapping of resistance gene(s), their deployment over time and space, and, thus, better management of white rust disease in B. juncea. [ABSTRACT FROM AUTHOR]

Here, the symbiotic palaemonid shrimp Hamodactylus boschmai is recorded from Korean waters for the first time, based on specimens collected from different invertebrate hosts by trimix diving at depths of between 45 and 60 m in Jejudo Island. This species can readily be distinguished from its congeners by the presence of a distinct supraorbital tooth, the proximal segment of the antennular peduncle having a single tooth on the distolateral margin, the presence of a denticulate lamina along the entire cutting edge of the fingers of the first pereiopod chela, and the chela of the second pereiopods having a strongly hooked tip on the movable finger. An illustrated description, colour photographs, and a comparison of partial mitochondrial cytochrome c oxidase subunit I gene sequences are provided. Résumé: La crevette Palaemonidae symbiotique Hamodactylus boschmai est signalée des eaux coréennes pour la première fois, à partir de spécimens collectés sur différents hôtes invertébrés en plongée trimix à des profondeurs de 45 à 60 m au large de l'île de Jejudo. Cette espèce peut être facilement distinguée de ses congénères par la présence d'une dent supraorbitale distincte, par le segment proximal du pédoncule antennulaire possédant une seule dent au bord disto-latéral, par la présence d'une lamelle denticulée tout au long du bord tranchant des doigts de la pince du premier péréiopode, la pince du second péréiopode présentant une extrémité fortement recourbée du doigt mobile. Une description illustrée, des photographies couleurs, et une comparaison des séquences partielles du gène de la sous-unité I de la cytochrome c oxydase mitochondriale sont fournies. [ABSTRACT FROM AUTHOR]

Morphological and molecular characterization of clinostomid metacercariae (CMc) was performed with the specimens collected in fish from Korea and Myanmar. Total 6 batches of clinostomid specimens by the fish species and geographical localities, 5 Korean and 1 Myanmar isolates, were analyzed with morphological (light microscopy and SEM) and molecular methods (the cytochrome c oxidase 1 gene and internal transcribed spacer 1/5.8S rRNA sequence). There were some morphological variations among CMc specimens from Korea. However, some morphometrics, i.e., the size of worm body and each organ, ratio of body length to body width, and morphology of cecal lumens, were considerably different between the specimens from Korea and Myanmar. The surface ultrastructures were somewhat different between the specimens from Korea and Myanmar. The CO1 sequences of 5 Korean specimens ranging 728-736 bp showed 99.6- 100% identity with Clinostomum complanatum (GenBank no. KM923964). They also showed 99.9-100% identity with C. complanatum (FJ609420) in the ITS1 sequences ranging 692-698 bp. Meanwhile, the ITS1 sequences of Myanmar specimen showed 99.9% identity with Euclinostomum heterostomum (KY312847). Five sequences from Korean specimens clustered with the C. complanatum genes, but not clustered with Myanmar specimens. Conclusively, it was confirmed that CMc from Korea were morphologically and molecularly identical with C. complanatum and those from Myanmar were E. heterostomum. [ABSTRACT FROM AUTHOR]

Background: Dicyemids are parasites found in the renal sac of cephalopods. The first species of dicyemid was found from kidneys of the Korean common octopus Callistoctopus minor. Objectives: This study aimed to identify the dicyemid and investigate the effect on renal sac of host. Methods: In this study, we compared the morphological characteristics of isolate to dicyemids (Dicyema sphyrocephalum, Dicyema clavatum, and Dicyema dolichocephalum) reported from C. minor in Japan. We compared the 18S ribosomal RNA (rDNA) and cytochrome c oxidase subunit I (COI) sequences of isolate to the sequences of D. shyrocephalum and D. clavatum. The infected octopuses renal tissues were histologically compared with the tissues of uninfected individuals. Results: The morphological characteristic of this isolated species corresponds to D. sphyrocephalum. The sequences similarities of 18S rDNA and COI gene of isolate are 99.7% and 98.1% with D. sphyrocephalum. We observed morphological changes in the epithelia folds of kidney at the dicyemids attached areas. Conclusions: The present study identified the isolate as D. sphyrocephalum and this is the first report of dicyemid species from Republic of Korea. Further studies on the effects of dicyemids on growth and health status of cephalopods will be needed. [ABSTRACT FROM AUTHOR]

During the study of the enchytraeid fauna of South Korea, specimens were found, which were identified as Bryodrilus ehlersi based on their morphological characters. This was an unexpected result since this species is common in Northern and Central Europe but has not yet been found in the Far East. Furthermore, sequence analysis of the mitochondrial cytochrome c oxidase subunit I gene, the nuclear histone 3 gene and the nuclear ribosomal ITS region showed unambiguously that the specimens collected in South Korea represent a different evolutionary lineage. In this paper, the detailed morphological and molecular comparison of Bryodrilus ehlersi specimens collected from various sites and countries are presented. Although the Korean specimens could not be formally described as a different species due to the lack of studied specimens from the type locality, clear evidence of cryptic genetic diversity was found within Bryodrilus ehlersi. [ABSTRACT FROM AUTHOR]

Ticks and tick-borne diseases are important issues worldwide because of their effects on animal and human health. The genus Ornithodoros, which is included in the family Argasidae, is typically associated with wild animals, including seabirds. In this study, samples from the nests of seabirds and surrounding soil were collected to investigate Ornithodoros spp. from 9 uninhabited islands in the western, eastern, and southern parts of Korea from April 2017 to October 2018. The islands are known as the breeding places of migratory and resident birds. Ticks were collected from soil and nest material of seabirds using a Tullgren funnel and identified using 16S rRNA and the cytochrome c oxidase 1 gene (COI), and host animals of soft ticks were identified using the mitochondrial DNA cytochrome b gene by a polymerase chain reaction. In the sequence identity of the 16S rRNA gene fragment of Ornithodoros sp., Ornithodoros sawaii was identified as the closest homologous sequence, and the new Ornithodoros sp. was newly identified. We found that the newly identified Ornithodoros sp. in the Republic of Korea was located in uninhabited islands used as breeding places by the black-tailed gull, Larus crassirostris. [ABSTRACT FROM AUTHOR]

A new species of pseudocrangonyctid amphipod, Pseudocrangonyx wonkimi sp. nov., was found in the groundwater of a cave in the southwestern Korean Peninsula. Pseudocrangonyx wonkimi sp. nov. is morphologically most closely related to P. joolaei Lee et al., 2020. However, P. wonkimi is clearly distinguished from P. joolaei by lacking sternal gills, fewer setae on maxilla 1 inner plate, fewer serrate robust setae on the carpus of the gnathopods, lacking bifid setae on the inner ramus of pleopod 3, and fewer articles of rami on pleopod 3. We also determined sequences of mitochondrial cytochrome c oxidase subunit I (COI) of P. wonkimi sp. nov. for molecular diagnosis. From the molecular analysis based on COI sequences, P. wonkimi showed the closest relationship with P. joolaei with 15.1% genetic distance. [ABSTRACT FROM AUTHOR]

Genus Zacco specimens collected in this study were classified genetically as five species, Zacco platypus, Z. temminckii, Z. koreanus and two unidentified species, using DNA barcoding analysis based on 655 bp of mitochondrial cytochrome c oxidase subunit I (COI) gene. Two of unidentified species (Z. sp.1 and Z. sp.2) were considered to be unrecorded or new species of genus Zacco according to genetic distances between Zacco species. In addition, we determined a natural hybrid based on polymorphic base at the diagnostic positions displayed on nuclear recombination activating gene 1 (RAG1) gene (965 bp), and estimated paternal and maternal species of natural hybrid comparing phylogenetic tree between COI and RAG1, and Z. sp.1♀ × Z. koreanus♂, Z. sp.2♀ × Z. koreanus♂ and Z. koreanus♀ × Z. sp.1♂ individuals were confirmed. The habitat of natural hybrids of Z. koreanus between Z. sp.1 and Z. sp.2 was identified as Geum and Yeongsan River, respectively. In our data, only F1 hybrid generation was identified; however, generations after F1 hybrid or backcross were not demonstrated. [ABSTRACT FROM AUTHOR]

A detailed description and illustrations of a new terebellid species are provided, and molecular information based on partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene are included. The new species, Neoamphitrite undevigintipes sp. nov., is described from the deep sea off the eastern coast of South Korea. It is similar to Neoamphitrite groenlandica (Malmgren, 1866) in that the thorax has 19 notopodial chaetigers. However, Neoamphitrite undevigintipes sp. nov. is clearly distinguishable from N. groenlandica in having the uncini of the first abdominal chaetiger arranged in a single row and in having 12 ventral shields. A taxonomic key to all known Neoamphitrite species is also included. [ABSTRACT FROM AUTHOR]