• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.313-314
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• 2001

The palaemonid shrimp Exopazaemon modestus inhabits the freshwater of the Indo-West Pacific, Siberia, Manchuira, Korea, China, Taiwan (Holthuis, 1980) and is abundant in the fresh water areas of southwest of Korea. Palaemonid shrimps are adapted to a variety of habitats in freshwater, brackish and marine environments. They play important role in the ecosystem of fresh, brackish and marine waters, acting as predators feeding on algae, detritus, crustaceans and meiofauna (Bell and Coull, 1978) and in turn, as preys for fishes and other predators (Anderson, 1985). (omitted)

• Journal of Species Research
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• v.9 no.4
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• pp.480-488
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• 2020

The genus Eurycletodes Sars, 1909 is reported for the first time in Korea. A new species of the genus Eurycletodes was collected from Hansando Island, South Sea of Korea. So far, Eurycletodes comprises 27 species, with no previously recorded species reported in East Asia, including Korea. Eurycletodes (Oligocletodes) vadumus sp. nov. is morphologically most closely related to E. (O.) denticulatus Por, 1967, E. (O.) aculeatus Sars, 1920, and E. (O.) diva Menzel, 2011, but clearly distinguishable from the others based on the following morphological characteristics: absence of A2 exopodal seta, A1 last segment with two inner setae, P4 exp-3 proximal inner seta modified, the ratio of length and of caudal rami (1.6 times), and mandibular palp with three setae. Together with the new species, the number of valid species in this genus has risen to 28. A key to species of the genus Eurycletodes is provided.

• Animal cells and systems
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• v.15 no.1
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• pp.63-72
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• 2011

A new species belonging to the genus Cyclopinoides Lindberg, 1953 (Cyclopinidae) is described from three beaches in Korea and Japan, as the first record of the genus from the Pacific. Among five species currently recognized in the genus, the new species resembles C. schulzi Herbst, 1964 from the Red Sea in sharing the character combination of 20-segmented antennule and stumpy caudal rami. However, C. orientalis n. sp. differs from it by relatively longer caudal rami (2.5-2.8 times as long as wide in female and about 1.6-1.8 times in male, while less than 2 times in female and about 1.3 times in male of C. schulzi), and by the transformation of an outer distal spine to a slender seta on the distal exopodal segment of leg 4. Moreover, C. orientalis n. sp. is discernible from C. schulzi in having a pyriform copulatory tube (against elongated tubular style in C. schulzi). A key to the species hitherto known in the genus is provided.

• Journal of Species Research
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• v.12 no.3
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• pp.244-257
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• 2023

The family Ameiridae Boeck, 1865 (Copepoda; Harpacticoida) consists of about 380 species in 47 genera, but only 10 species have been reported in Korea. A benthic ameirid species was collected from the East Sea of Korea. Specimens were identified as members of the genus Ameiropsis Sars G.O., 1907, and this is the first record of the genus Ameiropsis in the Pacific Ocean. Ameiropsis gyeongjuensis sp. nov. is morphologically similar to A. mixta Sars G.O., 1907 and A. longicornis Sars G.O., 1907 from Norway. However, the new species is clearly distinguishable from the others based on the following morphological characteristics: the proximal segment of antennary exopod with a bulge in the middle, and with one pinnate seta; the distal segment of antennary exopod with a thickened, blade-shaped outer seta; and female P5 baseoendopod with five setae and exopod with six setae. An identification key to species is provided for the 11 valid species of the genus Ameiropsis.

• Korean Journal of Environmental Biology
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• v.39 no.4
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• pp.590-603
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• 2021

Benthic harpacticoids were collected from the East Sea of Korea. Specimen were identified as members of the genus Robertgurneya Apostolov & Marinov, 1988 based on the following characteristics: the fourth segment of antennule with aesthetasc, antenna with three-segmented exopod, shape of mandible, and P1-P4 armature formula. Robertgurneya donghaensis sp. nov. is morphologically most closely related to R. simulans (Norman & Scott T., 1905) and R. similis similis (Scott A., 1896). However, R. donghaensis is characterized by the rostrum with a pointed tip, caudal rami about as board as the length of its inner edge, the first segment of the P1 endopod much longer than entire exopod, and the P5 exopod with five setae in male. The genus Robertgurneya is reported from Korean waters for the first time.

• Animal Systematics, Evolution and Diversity
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• v.39 no.4
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• pp.309-313
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• 2023

Polygordiidae is recorded as a new record in the Korean fauna. Twenty-three specimens of Polygordius pacificus were collected from the low intertidal zone with coarse sandy bottom on the eastern coasts of Korea. Morphologically, there was no doubt that the specimens are close to the holotype of P. pacificus, particularly due to the presence of elongated and longitudinal pygidial glands, and the length to width ratio. The prostomium of the Korean specimens have a rounded shape that is similar to subsequent research using scanning electron microscope. The DNA sequence comparison of the mitochondrial cytochrome c oxidase subunit I (COI) between Korean and Japanese population supports the identification of present specimens.

• Animal Systematics, Evolution and Diversity
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• v.39 no.4
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• pp.289-294
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• 2023

We discovered a halacarid mite species, Isobactrus tuberculatus Abé, 1996, inhabiting marine plastic debris on the coast of Jeju Island, Korea. The key characteristics of these Korean specimens were consistent with those in the original description of specimens from Hokkaido, Japan, including the presence of tuberculate membranous cuticles between the anterior and posterior dorsal plates, fusion of the posterior epimeral plates I and II, tibia II with a bipectinate seta, tibiae III and IV each with five setae, and a pair of subgenital setae in females. However, two small morphological differences were noted: the distance between the anterior and posterior dorsal plates was shorter than that in Japanese specimens, and the location of dorsal seta-2 was closer to the anterior dorsal plate in Korean specimens. We herein provide detailed illustrations of I. tuberculatus, based on the Korean specimens, with a brief taxonomic comment on the similarities among allied congeneric species. The genus Isobactrus is first reported in Korea.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.27 no.2
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• pp.103-125
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• 2022

This study aims to identify the community characteristics of meiofauna inhabiting the Yellow Sea continental shelf. To this end an annual survey was conducted considering the seasons from 2018 to 2020 at 13 stations with a depth of 18~90 m of the Yellow Sea located at latitudes 35, 36 and 37 degrees north latitude. The survey was conducted in three seasons of spring, summer, and autumn at 5 stations in October 2018, 9 stations in April 2019, and 6 stations in August 2020 was used to collect 3 repetitions at each station. The habitat density of meiobenthos in the surveyed area was in the range of 45~1029 inds./10 cm², which was similar to the previous studies conducted in the Yellow Sea. The density of meiobenthos according to the seasons was 800±69 inds./10 cm² in autumn, the highest, and the lowest at 260±48 inds./10 cm² in summer. A total of 19 taxa appeared in meiobenthos, and the average value showed the number of nine taxa. Among the appearing taxa, the most dominant taxon was nematodes, accounting for 80.8% of the total density, followed by benthic copepods (8.8%) and benthic foraminifers (4.7%). As for the size distribution of medium benthic animals, the density of organisms corresponding to the size of 63~125 ㎛ was the highest, and 1~0.5 mm was the lowest. As for the vertical distribution in the sediments of medium benthic animals, the habitat density gradually decreased as the depth increased in the sediment surface layer. As a result of analysis of the N/C ratio, MPI, and ITD index using medium-sized benthic animals to identify the benthic environment, there were differences by season, but no values indicating pollution overall.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.43-55
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• 2004

Meiobenthic community structure was studied in intertidal mud flat and sand flat of Yeochari in Ganghwado in May and August, 1998. Sixteen groups of meiofauna were found at all study sites in the Yeochari tidal flats. Nematodes were the most dominant animal group among the meiofaunal groups as a whole. Sarcomastigophorans, harpacticoid copepods, nauplius larvae of crustaceans and ciliophorans which were also important components of the meiofaunal community. All of these five faunal groups comprised more than 90% of total meiofauna. The maximum total density of meiobenthos was $5.8{\times}10^6ind./m^2$ at the station of sand flat in August and the minimum density was $4.0{\times}10^6ind./m^2$ at same station in May. Biomass of meiobenthos was $1.5g/m^2$(May), $2.3g/m^2$(August) at mud flat and $1.7g/m^2$(May), $2.6g/m^2$(August) at sand flat. At the station of mud flat in May, the highest density was observed within 1cm in depth of upper sediment and steeply decreased increasing depth of sediment. At the sand flat station in August, the highest density was also observed within 1cm in depth of upper sediment and decreased with depth, while the concentration of the animals at the surface was not conspicuous as the mud flat. The value of N/C(nematodes/benthic harpacticoids) ratio was the highest at the station of sand flat in May and the lowest at the sand flat in August.

• Ocean and Polar Research
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• v.33 no.3
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• pp.193-209
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• 2011

The community structure of meiobenthos was studied at 16 stations within sandy tidal and subtidal zones in Jangbongdo in the Yellow Sea, Korea from Aug. 2006 to Jan. 2007. Meiobenthic organisms were collected by three core samples, with a 3.6 cm diameter, from each sediment sample taken with a Smith-McIntyre Grab. Mean grain size of study stations ranged from $1.49{\phi}$ to $3.55{\phi}$. Composition of sand ranged from 80.38% to 99.89%. There was reduction in total abundance and biomass of meiobenthos from summer to winter. Total densities of meiofauna ranged between 17 inds./10 $cm^2$ and 853 inds./10 $cm^2$. Nematodes, gastrotricha, nauplius and harpacticoids appeared as major taxa in decreasing order. This study shows that major taxa comprised 90 percent of total abundance. Most meiofaunal organisms are concentrated in the upper sediment layers and the total abundance and biomass of organisms in the tidal zone is higher than the subtidal zone.