• Animal Systematics, Evolution and Diversity
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• v.40 no.2
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• pp.130-134
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• 2024

The family Velutinidae is found in various intertidal and subtidal habitats worldwide including Arctic and Antarctic seas. They are characterized by possessing a fragile shell that is partially or entirely covered by the mantle. Eight valid species of the genus Coriocella have been reported mostly in the Indo-West Pacific. Here we report Coriocella jayi Wellens, 1996 from Korean waters for the first time and describe details of their external morphology and radula characteristics using scanning electron microscopy, and provide the mtDNA cox1 sequence as a DNA barcode sequence information. This species is distinguished from other congeneric species by having six cylinder-shaped tubercular lobes of their dorsal part of mantle body and mantle color. Phylogenetic tree using the mtDNA cox1 sequence data shows that two Coriocella species (C. jayi and C. nigra) are grouped as their respective sister among Velutinidae species, and these relationships are strongly supported by 100% bootstrap value. Despite the morphological similarities, further investigation will be needed to confirm whether the African and Korean populations can be justified as the same species with a disconnected distribution range, or represent morphologically similar but two distinct species.

• Animal Systematics, Evolution and Diversity
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• v.40 no.3
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• pp.167-210
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• 2024

Twelve species of cyclopoid copepods, including two new genera and ten new species, associated with polychaetes are described from Korea. The new taxa comprise Petalocopus planus n. gen. n. sp. in the Clausidiidae, Rhodinicola exilis n. sp. in the Clausiidae, Gastrodelphys vadicola n. sp. in the Gastrodelphyidae, Polyankylis estivalis n. sp. in the Polyankyliidae, Pentakela cylindrica n. gen. n. sp., Pseudanthessius oporinus n. sp. and P. petilus n. sp. in the Pseudanthessiidae, and Myxomolgus buanensis n. sp., M. dokdoicus n. sp. and Serpuliphilus antennatus n. sp. in the Sabelliphilidae. As characteristic features of the new genera, Petalocopus n. gen. has a pair of pedunculate suckers on the terminal segment of the antenna and an enlarged posterodistal seta on the second segment of antennule, and Pentakela n. gen. has five strong hooks on distal segments of antenna, three-segmented exopod and two-segmented endopod in legs 1 and 2, and one-segmented exopod and a lobate, rudimentary endopod in legs 3 and 4. The male of Maxilliclausia propria Kim, 2014 of the Clausiidae is recorded for the first time. Nereicola ovata Keferstein, 1863 known previously only in European waters is redescribed based on a newly collected female specimen from Korea.

• Animal Systematics, Evolution and Diversity
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• v.40 no.3
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• pp.211-220
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• 2024

During the surveys of ciliates from hypoxic habitats, three marine anaerobic species were found: Metopus spiculatus, M. vestitus, and Muranothrix felix. These species have not been previously recorded in South Korea and belong to the taxonomic classes Armophorea and Muranotrichea. The morphology of these species was examined by both microscopic observations of live specimens, and stained cells using protargol impregnations. Metopus spiculatus has the following characteristics: body size 80-110×25-35 ㎛ in vivo, beak-like structure at the end of preoral dome, ectosymbiotic bacteria covering cell surface, intracytoplasmic needle-shaped structures and the conspicuous tail end. Metopus vestitus has the following distinguishing characteristics: body size 95-130×25-45 ㎛ in vivo, a cone-shaped body, a covering of ectosymbiotic bacteria on its cell surface, intracytoplasmic needleshaped structures, somatic kineties arranged in 26-28 longitudinal rows, and a posterior part tapered into a tail. Muranothrix felix has the following characteristics: body size 100-130×20-30 ㎛ in vivo, elongated body with twisted neck region, bristle-like cilia protruding perpendicular to the cell margin, ectosymbiotic bacteria covering the cell surface, about 10 macronuclear nodules, and a long, stiffened caudal cilium.

• Animal Systematics, Evolution and Diversity
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• v.40 no.3
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• pp.221-253
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• 2024

Eight new species of the genus Acanthomolgus are described as external associates of octocorallian corals from Korea. As diagnostic features of these new species, A. taenichaetatus n. sp. has ribbon-like distal caudal setae; A. jei n. sp. and A. crassae n. sp. have no inner proximal expansion on the exopodal segment of female leg 5, and the former species has only three setae on the maxillule (vs. four setae in other seven species). Acanthomolgus notialis n. sp. is similar to A. oporinus n. sp. in having a rounded inner proximal expansion on the exopodal segment of female leg 5, but the latter species is distinguished from the former by having longer caudal rami which are about 1.5 times longer than wide, by having a longer inner seta of the maxilla which is three quarters as long as distal lash, and by having unequal setae on the basis of maxilliped. Acanthomolgus dokdoicus n. sp., A. rugosus n. sp. and A. triplus n. sp. appear to be similar to one another in having an ear-like inner proximal expansion on the exopodal segment of female leg 5, but the genital double-somite of the female is distinctly longer than wide in A. rugosus n. sp. (wider than long in other two species), and the third endopodal segment of the antenna is distinctly shorter than the first endopodal segment in A. triplus n. sp. (vice versa in other two species). This is the first record on the genus Acanthomolgus in the temperate West Pacific.

• Animal Systematics, Evolution and Diversity
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• v.34 no.3
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• pp.127-142
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• 2018

A new species of Eudactylopus Scott A., 1909 is described from the southern coast of Korea. The specimens were collected using a light trap set overnight at the entrance near a pier. Eudactylopus yokjidoensis n. sp. is similar to E. andrewi Sewell, 1940 and E. spectabilis (Brian, 1923) in two key respects: similar length of proximal and distal inner setae on female P2 enp-2, and modification of two subapical setae on male P2 endopod. However, E. yokjidoensis can be differentiated from the two species by following morphological characteristics: in females, the length ratio of cephalothorax/2nd-4th thoracic somites combined is smaller in E. yokjidoensis than other two species (1 : 0.8 vs. 1 : 1); antennule has nine segments (vs. 7-segmented in E. andrewi); P2 to P4 each bears a process in medial distal margin of basis, while it is just smooth in E. spectabilis; in males; the length ratio of cephalothorax to 2nd-4th thoracic somites combined is smaller in E. yokjidoensis than other two species (1 : 0.6 vs. 1 : 1 in E. andrewi and 1 : 0.8 in E. spectabilis); and P5 exopod has a comb-like innermost seta, while it is bipinnate seta in E. spectabilis. To prove the Korean species of Eudactylopus to be new, full descriptions of both sexes are given here, and the claim is supported by distinct genetic differences between E. yokjidoensis and E. spectabilis (22.3-22.7%) in the mitochondrial gene cytochrome oxidase subunit I(mtCOI) sequence.

• Journal of radiological science and technology
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• v.41 no.4
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• pp.305-312
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• 2018

The incidence of cardiovascular disease increases rapidly after 40's. The thickness of the epicardial adipose tissue was measured to analyze the risk factors affecting the thickness change. We present the cut off value for the epicardial adipose tissue thickness for high impacted variables. For the study, 547 patients underwent echocardiography, epicardial adipose tissue thickness, body mass index, abdominal subcutaneous fat thickness and diabetes mellitus were used as analytical variables. As a result, multiple regression analysis of age group showed that diabetes mellitus was highly influential in all age group, so we could predict the cut off value for the epicardial adipose tissue thickness for diabetes mellitus. As a result of ROC curve analysis, cut off value of 7.44 mm was obtained with sensitivity of 79.6% and specificity of 60.6% for diab etes variab le. Logistic regression analysis b ased on this value showed that the risk for diab etes increased 6 times with each increase in the thickness of the epicardial adipose tissue. Among the various obesity indexes, epicardial adipose tissue is used as an important index especially to prevent the risk of cardiovascular disease. Therefore, we suggest that the use of echocardiography as a routine screening method for the prevention of cardiovascular disease and metabolic syndrome, which is rapidly increasing in patients over 40's age, will enable more effective monitoring. Radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium.

• Animal Systematics, Evolution and Diversity
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• v.36 no.2
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• pp.154-158
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• 2020

The Asian crested ibis Nipponia nippon is one of the world's most endangered species. Except for the Sanxii population from China, it is known that all of the crested ibis populations from East Asia have been extinguished. In these days, most of them are being inbred as captive populations in China, South Korea, and Japan, which caused their low expected genetic diversity. Microsatellite markers are well known as a suitable DNA marker for exploring genetic diversity among captive populations of a variety of endangered species. In the present study, ten microsatellite markers were developed for the captive populations of the South Korean crested ibis, which were employed to examine the level of genetic diversity with the two founders from Sanxii, China and the 70 descendants of them. As a result, the mean number of gene diversity, observed heterozygosity, and expected heterozygosity of the captive population were 0.70, 0.84, and 0.70 respectively. It revealed that the captive population of South Korea is as genetically more stable than we expected. In addition, the principal coordinates analysis and genetic structure analyses showed that the captive population of N. nippon can be divided into the two different genetic groups. The developed microsatellite markers here could be helpful for crested ibis conservation in East Asian countries such as China and Japan as well as South Korea.

• Animal Systematics, Evolution and Diversity
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• v.32 no.1
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• pp.28-37
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• 2016

We describe the morphological characteristics of two morids, Gadella jordani and Physiculus japonicus, belonging to the order Gadiformes, based on Korean specimens collected from the Korean ocean. Two specimens of Gadella jordani was first collected from Jeju Island, Korea and the East Sea, Korea, in 2013-2014. This species is characterized by 8, 67-69 dorsal fin rays, 66-71 anal fin rays, 5+13 gill rakers, no barbel on the lower jaw, no vomerine teeth, and a ventral luminous organ closer to the anus than to the interventral line. We described it as the first record to the Korean fish fauna, and proposed the new Korean name "Min-su-yeom-dae-gu-sok" for the genus Gadella, and "Min-su-yeom-dae-gu" for the species G. jordani. Physiculus japonicus was first reported by Koh and Moon in the year 1999 based on a single specimen in Korea. However, no study has been attempted to describe the morphological characteristics in Korea since then. In 2013-2014, three specimens of P. japonicus was collected from Jeju Island, Korea and the East Sea, Korea, and we redescribe P. japonicus in detail. This species is characterized by 9-10, 63-64 dorsal fin rays, 70-73 anal fin rays, 3+7-8 gill rakers, a short barbel on the lower jaw, and a ventral luminous organ equidistant between the interventral line and the anus.

• Animal Systematics, Evolution and Diversity
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• v.28 no.3
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• pp.215-219
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• 2012

To examine genetic divergences of two endemic Sorex caecutiens subspecies from Korea (S. c. hallamontanus in Korean Jeju Island and S. c. annexus in the mainland Korean Peninsula), we obtained partial cytochrome oxidase I (COI) sequences (429 bp) and complete cytochrome b sequences (1,140 bp) from the two Korean subspecies, and we compared these sequences to the corresponding sequences of S. caecutiens, obtained from GenBank. We found that Jeju S. c. hallamontanus is one of three clades within S. caecutiens, with an average Jukes-Cantor distance of 1.57% in the COI sequences and the distance of 2.07% and 11 fixed site differences in the cytochrome b sequences, indicating that Jeju S. c. hallamontanus is one endemic subspecies with concordant genetic distinctness, although further analyses with nuclear DNA sequences are necessary to confirm these findings. However, S. c. annexus from the mainland Korean Peninsula was not divergent from S. c. macropygmaeus from northeastern China and adjacent Russia, indicating that S. c. annexus from the mainland Korean Peninsula is another endemic subspecies with only morphological differences, although it is necessary to reexamine the subspecies status of S. c. annexus.

• Animal Systematics, Evolution and Diversity
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• v.28 no.3
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• pp.192-207
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• 2012

To supply the morphological and ecological information of oligotrich ciliates in Korea, water samples were seasonally collected in Gwangyang Bay and Jinhae Bay from August, 2010 to February, 2012 and processed by quantitative protargol staining method. As a result, six species belonging to the genus Strombidium Clapar$\grave{e}$de and Lachmann, 1859 are identified: Strombidium emergens Kahl, 1932; S. dalum Lynn et al., 1988; S. epidemum Lynn et al., 1988; S. tressum Lynn et al., 1988; S. bilobum Lynn and Gilron, 1993; S. pollostomum Lynn and Gilron, 1993. These six species were newly reported from Korean coastal waters. Strombidium emergens is a middle sized Strombidium ($20-50{\mu}m$ in length) and has open and deep oral groove to girdle portion. Strombidium dalum is a small sized Strombidium (${\geq}20{\mu}m$ in length), that has torch-like spiral anterior membranelles and an inverted triangles-shaped macronucleus on the posterior pole. The small sized S. epidemum has conspicuous trichites surrounding the girdle portion and ventral membranelles distinctly separated from anterior membranelles. The small sized S. tressum has torch-like spiral and extremely long trichites among the cilia of anterior membranelles. The middle sized S. bilobum has a bilobed macronucleus. Strombidium pollostomum is also a small sized Strombidium but its ventral membranelles are continuously connected with anterior membranelles. The five species except S. emergens occurred frequently over the wide range of water temperatures and salinities.