• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.12a
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• pp.52-52
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• 2004

• The Korean Journal of Zoology
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• v.34 no.3
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• pp.307-322
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• 1991

The systematic study of recent freshwater ostracods was conducted on the materials collected from 44 localities in South Korea. Four species of ostracods were identified, all of which were new to South Korea: Stenocypri'shislopi Ferguson,1969, Cypretta seuroti 6autier,1929, Potomocypris producta (Sars, 1924), and llyocvpris dentifero Sars. 1903.

• 한국전자현미경학회:학술대회논문집
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• 2004.11a
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• pp.105-110
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• 2004

Cavernocypris gosuensis n. sp. (Cyprididiae, Cypridopsinae), a new subterranean ostracod species is described with figures of female valves, mouthparts, appendeges and SEM photos from Gosu cave, Danyang-Gun, Chungcheongbuk-Do in Korea. The new stygobiont speices is sixth of the genus Caveroncypris Hartmann, 1964 that characterized by both valeves with a median concave part in ventral view and two groove lines in dorsal view, the reduction of the furca, which is flagellum like in female and the left valve ventrally overlaps the right valve when the carapace is closed and can be distinguished from its congers by left valve with 6 muscle scars in innerpart, mandible palp with one claw and 3 setae on the terminal segment and without seta on the exterodistal border of segment III. The animals were collected within pH 7.31-8.74, temperature ($^{\circ}C$) 13.0-14.6 and dissolved oxygen (mg/l 6.75-14.84 from Aug.2003 to Sep.2004.

• Animal Systematics, Evolution and Diversity
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• v.7 no.1
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• pp.81-100
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• 1991

The systematic study of recent freshwater ostracods were conducted on the materials collected from 48 localities in South Korea. Four species of ostracods are identified, and all of them are new to South Korea : Cyprinotus uenoi Brehm , 1936, Heterocypris incongruens (Ramdohr, 1808), Dolerocypris fasciata(O.F.Mller, 1776 ), Dolerocypris sinensis Sars, 1903. Up to now seven species (5 species and 2 subspecies ) of recent ostracods are known to South Korea.

• Journal of Species Research
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• v.6 no.spc
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• pp.38-50
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• 2017

This study describes a new species of cytheroid ostracod, Paradoxostoma koreana sp. nov., collected in Korea. In addition, three other cytheroid ostracods, P. setoense Schornikov, 1975, Loxoconcha pulchra Ishizaki, 1968, and Ishizakiella miurensis (Hanai, 1957), are reported with brief descriptions and images. Paradoxostoma setoense and L. pulchra were previously only known from Japan, while I. miurensis was previously reported from Korea. Here, we describe variability in hemipenis morphology observed in the Korean population. The new species is closely related to several East Asian species, but its sister species is P. rhomboideum Okubo, 1977. The primary difference between the new species and P. rhomboideum is morphology of the distal projections of the hemipenis, but minor differences exist in the details of the cheatotaxy of other appendages. This report also provides a list of all East Asian Paradoxostomatidae.

• Journal of Species Research
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• v.1 no.1
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• pp.68-77
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• 2012

Ishizakiella supralittoralis (Schornikov, 1974) was collected from rock pools near Busan, South Korea, and is redescribed herein. It is the first record of this species from Korea, and also the first finding of a living population of Ishizakiella McKenzie & Sudijono, 1981 from the continental margins. Here we also comment on the diversity of Ishizakiella in Japan, possible existence of cryptic species, and provide a key to all six currently known species of this genus, including the two fossil ones.

• Journal of Species Research
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• v.9 no.2
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• pp.122-130
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• 2020

Cavernocypris reddelli n. sp. is a new species of the genus Cavernocypris collected from spring waters of Texas, U.S.A.. This is the sixth species of the genus described so far. It can be distinguished from the other species of the genus by the shape and length of carapace, presence of robust marginal pore canals on right valve, number and length of setae on second antenna, shape of hemipenis, numbers of whorls on the Zenker organ, and differences in other parts of chaetotaxy. The new species was compared with other species and a new taxonomic key for the genus is presented for future studies.

• Journal of Species Research
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• v.10 no.3
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• pp.255-261
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• 2021

Sclerochilus Sars, 1866 is the most diverse genus of the family Bythocytheridae, one of the longest surviving groups of extant ostracods, and the oldest representative of the superfamily Cytheroidea. It has a worldwide distribution at various marine depths, and it includes three subgenera: Fascichilus Schornikov, 1981; Praesclerochilus Schornikov, 1981; and Sclerochilus Sars, 1866. We describe Sclerochilus(Praesclerochilus) jejuensis sp. nov. from Jeju Island, South Korea, raising the number of known Praesclerochilus species to 13. Although most species belonging to this subgenus have very similar carapace shape, the new species differs morphologically from its most similar congeners, S. (P.) mukaishimensis Okubo, 1977; S. (P.) pruniformis Schornikov, 1981; and S. (P.) ochotensis Schornikov, 1981, by the large ventral process on the hemipenis. So far, 29 Sclerochilus species have been reported from South Korea, only one of which was named, but for which no descriptive information was provided. Therefore, this is the first taxonomic report of a Sclerochilus species from South Korea.

• Korean Journal of Environmental Agriculture
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• v.32 no.1
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• pp.24-34
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• 2013

BACKGROUND: This study was carried out to compare population size of mudfish (Misgurnus mizolepis) between the agricultural practices and to investigate the causes of its differences. We also provided basic information for sustainable use of mudfish population in paddy fields. METHODS AND RESULTS: Mudfish and benthic invertebrates which are diet of mudifish were investigated from 8 sites of organic and conventional rice paddy fields in South Korea. Total number of mudfish were 1,882 individuals in survey sites. Mudfish population were 2.4 times larger in organic paddy fields (1,333 individuals) than in conventional paddy fields (549 individuals). The population size of mudfish was larger in Mungyeong-si, Gyeongsangbuk-do and Anseong-si, Gyeonggi-do with relatively better environmental conditions than the other 5 sites including Suwon-si, Gyeonggi-do, Cheongyang-gun, Chungcheongnam-do, Gunsan-si, Jeollabuk-do, Gimje-si, Jeollabuk-do, Hwasun-gun, Jeollanam-do, Hamyang-gun, Gyeongsangnam-do. Benthic invertebrates collected from survey sites were 74 species, 68 genera, 46 families, 19 orders, 6 classes and 3 phyla. According to agricultural practices, benthic invertebrates were identified 66 species, 62 genera, 41 families, 17 orders, 6 classes and 3 phyla in organic paddy fields while there were 66 species, 60 genera, 42 families, 18 orders, 6 classes and 3 phyla in conventional paddy fields. Dominant invertebrates were Chironomidae sp., Branchiopoda sp., Ostracoda sp., and Copepoda sp. There were no differences in dominant species between organic and conventional paddy fields. Population size of mudfish tended to increase with the population size of Chironomidae sp., Branchiopoda sp., Ostracoda sp., and Copepoda sp. But, only population of Chironomidae sp. and Copepoda sp. statistically related to population size of mudfish. The number of individuals of mudfish (Misgurnus mizolepis) was higher at the low rate of urban area than any other surveyed region and was affected by appearance ratio of main preys such as Chironomidae sp. and Ostracoda sp. CONCLUSION(S): The population size of mudfish in rice paddy fields could be affected by environmental conditions and agricultural practices such as organic and conventional methods.

• Korean Journal of Organic Agriculture
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• v.26 no.2
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• pp.297-316
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• 2018

The golden apple snail (GAS, Pomacea canaliculata) is an invasive freshwater snail. The GAS was introduced in Korea without prior studies on the possibility of crop damage or its impact on the natural ecosystem. The freshwater apple snails can be found typically in ponds, rice paddies, irrigation canals, roadside ditches or slower portions of streams. In this study, we were carried out to investigate the assessment of physiological and ecological characteristics, environmental characteristics inhabited area in winter season and cause of massive death at one time of golden apple snails used for weed control in wet rice paddies. The GAS was introduced from Japan to Korea for commercial production as a dietary protein supplement. The golden apple snail was also used a recently for weed control in wet rice cultivation. The species of freshwater Pomacea snails is belonging to the genus Pomacea, family ampulariidae, order mesogastropoda, subclass pulmonata, class gastropoda, phylum mollusca. The GAS spread into irrigation ditches and natural waterways. It is now distributed in ponds and canals near rice fields of southern parts of the country and has overwintered. It increases its cold hardiness before winter. However, the physiological mechanism of cold hardiness in molluscs is poorly understood, especially in freshwater molluscs. Our results on physio-ecological characteristics of the Pomacea apple snail showed that the ratio of males to females was 1: 1.99~2.33. The daily growth was 87.7 mg in weight, 0.31 mm in height and 0.33 mm in width of the their shell. On the other hand, the golden apple snails were very high to resistance on drying condition and survived rate about 80% up to 3 months. The inhabitation of GAS was no statistical significant impacts on the water quality. An important property of aqueous solutions is agricultural water quality because it affects chemical and biochemical properties such as chemical reactions, equilibrium conditions, and biological toxicity. The death rate of weed control apple snails by Ostracoda (Stenocypris hislopi) was only 2.86% and 5.71% depending on the density. Therefore, GAS was not a direct death caused by Ostracoda (Stenocypris hislopi).