• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.475-483
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• 2012

Tribolodon hakonensis(Cypriniformes; Leuciscinae) is anadromous; they are born in freshwater, migrate back to the ocean, then return to their home stream for spawning from mid-March to early-June. Here, five microsatellites were used to assess the level of gene flow among T. hakonensis populations from the Samcheok-Oship Stream, South Korea. The frequencies of dominant alleles across several loci differed between down-and upstream populations divided by several weirs, and pairwise multilocus $F_{ST}$ estimate was significantly high(0.083). However, there were no signs of any loss of genetic variation in the upstream population. Assignment tests of individuals in admixture model(K=2) to a set of baseline samples showed fairly correct assignment to each cluster; all of upstream individuals sere included in the first cluster, while the majority of downstream individuals(65%) comprise the second cluster. These results indicate reduced gene flow between up- and downstream populations but allowing passive downstream drift. It is likely that man-made structures might at least partially be a factor for creating and consolidating the current distribution patterns of genetic variation among T. hakonensis populations in the Samcheok-Oship Stream. This information will assist governing agencies in making informed decisions regarding conservation of anadromous fishes in Korean drainage systems.

• The Korean Journal of Zoology
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• v.38 no.1
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• pp.87-95
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• 1995

한국산 담수어류의 잉어목, 황어아과(Leuciscinae) 어류 2속 5종의 계통적 유연관계를 구명하기 위하여 mtDNA분석을 실시하였다 6 base를 인지하는 10개의 제한효소를 처리하여 얻어진 강tDNA의 크기는 16.5-17.5 Kb였으며 Bcl I, Bgl I, Bgl II, Hin dIII, Pvu II, Xba I 등은 종간 차이가 뚜렷하였다. 각종의 집단간 mtDNA분화정도는 매우 낮았으나(p=1% 미만) M. oxyephalus의 무주집단과 제주집단은 예리적으로 큰 차이를 보였다(p=5.3%) Moroco속의 종간 분화정도를 비교한 결과 M. oxycephafus와 M. lagowsk서 사이가 평균 f=7.2%로 근면관계가 제일 가까웠고 M. keumkang과 M. semotilus는 타종들과 근연관계가 제일 멀었다. Moroco속과 Phoxinus속간의 평균 유전적 분화정도는 f=13.7%로 현저한 차이를 보였다. Brown 등(1979)의 공식을 이용하여 이들 황어아과 2속 5종의 분화시기를 추정한 결과 이들은 후기 선신세(Pliocene)와 흥적세(Pleistocene) 사이에 분화된 것으로 추정되었으며 이 결과는 동위효소 연구에서 얻어진 결파(Yang and Min, 1989)와 잘 일치한다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.381-400
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• 1985

Twelve species of subfamily Leuciscinae from Korea are reviewed and keys to species and genera are provided. The species include Tribolodon hakonensis, T. branti, Phoxinus phoxinus, Moroco oxycephalus, M. steindachneri, M. keumgang, M. semotilus, Zacco platypus, Z. temminckii, Opsariichthys uncirostris amurensis, Aphyocypris chinensis and Squaliobarbus curriculus. In the present study M. lagowskii and O. bidens recorded previously in Korea have to be classified to M. steindachneri and O.u.amurensis based on several characters such as caudal peduncle depth, their distributions and lateral line scales, etc. A. chinensis from Korea is easily distinguished from that of mainland China in head length and caudal peduncle length. The skull and weberian apparatus of M. keumgang, endemir to Korea are described and compared with the other species of this subfamily. The diploid chromosome number of 9 species has three patterns: 2n=50 (T. hakonensis, P. phoxinus, M. oxycephalus, M. steindachneri and M. keumgang), 2n=48(Z. platypus, Z. temminckii and A. chinensis), 2n=76 (O. u. amurensis). Polyploidization or intraspecific polymorphism of chromosome was not observed in any species studied. Both species of P. phoxinus and A. chinensis are shown to be electrophoretically distinct from other taxa examined. The genera of subfamily Leuciscinae in Korea are represented by three possible groups: 1) Zacco-Opsariichthys-Tribolodon-Phoxinus-Morco, 2) Aphyocypris, and 3) Squaliobarbus.

• Parasites, Hosts and Diseases
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• v.29 no.3
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• pp.217-226
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• 1991

Three morphological types of the genus Metagonimus were found encysted in the dace, Tribolodon tacganowskii, caught from the Sumjin River, Korea. They include Metagonimus Yokogawa type (M. yokogawai) , Miyata type, and Koga type according to Saito's classification. The metacercariae were experimentally fed to rats and hamsters and a total of 1,624 Metagonimus worms were recovered from their small intestine. The number of each type was 820 for Yokogawa type, 688 for Miyata type, 46 for Koga type, and 70 undetermined. The major differential keys between Yokogawa and Miyata types were in the position of two testes, distribution of uterine tubules, and size of the eggs, and the keys between Miyata and Koga types were in the position of two testes, distribution of vitelline follicles, and size of the eggs. The validity of Miyata type as a specific level should be retained until more convincing evidences are obtained. Koga type is regarded as a synonym of M. takahashii. The present results reveal that there are 3 morphological types of Metagonimus whose larvae are encysted in the dace, T. tacganowskii, from the Sumjin River. Key words: Metagcnimus yokogawai, morphological types, rats, hamsters, dace ( Tribolodon tacxanowskii) , Sumjin Rver.

• Journal of Marine Life Science
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• v.6 no.2
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• pp.106-116
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• 2021

To secure basic data by monitoring the growth of salmon (Oncorhynchus keta) released to the Taehwa River. After discharge, the characteristics of the young salmon distribution and migration rate habitat were investigated for two years. A total of 4 points [Sunbawi bridge (St.1), Guyeong bridge (St.2), Samho bridge (St.3), and Myeongchon bridge (St.4)] were investigated. The survey of 2017 indicating an increase of 10 mm in average length and 0.8 g in average weight, and the survey of 2018 indicating an increase of 10 mm in average length and 0.5 g in average weight. Among 39 species, 10 insectivorous and 12 omnivorous, are believed to compete with young salmon for food. 6, 5, 6 and 8 predatory fish species has emerged at each site, respectively. According to this study, it is believed that St.1 and St.2 points are more proper as discharge location of young salmon because these two points have less varied in depth, flow rate, salt concentration etc. In addition, it is thought that the night or dawn time in early January is the best discharge time of young salmon fish because predatory fish such as Korean piscivorous chub and bass etc. does not eat food actively at that time.

• Animal Systematics, Evolution and Diversity
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• v.3 no.1
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• pp.41-50
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• 1987

The osteological characters of Aphyocypris chinensis of subfamily Leuciscinae were examined and the systematic position of this species is discussed through comparison with other species of subfamilies Leucisicinae and Cultrinae. Numbers of the dorsal an danal fin ray, having no symphyseal knob and barbels and separation between dermosphenotic and supraorbital, are in acord with those of subfamily Leuciscine, and the abdominal keel and trigemino-facial nerve foramen of the prootic are more closely related with those of subfamily Cultrinae. But several diagnostic characters detected only in this species are as follows ; 4 infraorbitals, the shape of ethmoid, 5-6 hypurals, the broad orbital width, having no extrascapular, incomplete lateral line and considerable small size.

• Korean Journal of Environmental Biology
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• v.30 no.4
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• pp.319-327
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• 2012

This paper was the result of investigation on fish fauna of natural estuary at Seomjin River, Korea. The total number of fish species collected in this study was 68 species belonging to 26 families. Dominant species in number was Acheilognathus majusculus (relative abundance: 37.4%), subdominant was Tribolodon hakonensis (10.5%). There were seven migrating fishes including Anguilla japonica and T. hakonensis. There were twenty Korean endemic species including Acheilognathus koreensis and Acheilognathus somjinensis. Thirty five species belonging to eight families were collected in upper part of river that dominant species was A. majusculus (38.2%). Thirty seven species were collected in lower part of river that dominant species was A. majusculus (48.5%). Thirty four species were collected in near estuary that dominant species was T. hakonensis (42.6%). In the comparison result of condition factor for several main species populations of Seomjin River were better than Nagdong River populations having estuary barrage. It was considered that almost fish populations of mid-to lower Seomjin River without estuary bank have stable life with natural environment.

• Parasites, Hosts and Diseases
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• v.31 no.4
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• pp.331-340
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• 1993

This study investigate the epidemiological feature of Metagonimus infection in Kangwon-do (province). The average Infection rate of the surveyed inhabitants was 7.8% (83 positives out of 1, 067 examinees) by stool examination; male, 11.4% and female, 3.2%, respectively. The egg positive rate in residents in the Som river area was 7.3%, that of the Chuchon river area 6.3%, the Pyongchang river area 12.8%, the Tong river area 3.8%, the Hongchon river area 9.8%, and the Ohsip stream area of Samchok 8.0%,respectively. The average metacercarial infection rate of genus Metagonimus in the fish was 81.0% (256 positives out of 318 fish). The infected fleshes were Zacco platypus. Zacco teminki, Opswiichthys biens, Squdidis sp., Corqssius carassius, etc. in western Kangwon-do Meanwhile, in the Ohsip stream area of Samchok-gun, eastern costal Kangwon-do, the infected fish were Plecoglossus altivelis and Tribolodon hokonensis. The rats and dogs are infected with the metcercanae obtained from Zacco platypus and Opsariichthys biens, adult worms collected were Miyata type of Metagonimus with some M. takahashii. When infected with metacercariae from Plecoglossus ltivelis, Metagonimus yokogowai was only found. M. yoogawai and Metagonimus Mlyata type were fecund together in Tribolodon hakonenis in Ohsip stream area of Samchok, in the eastern Kangwon-do. The intestinal flukes of genus Metogonimus in western Kangwon-do were Miyata type of MetQnonimuT and M. takahashii transmitting mainly by Zacco platypus and Opsariichtys bidens as a source of infection. In the eastern part of Kangwon province (Ohsip stream area of Samchok), M. yokogowai was mainly distributed by P. altivelis and T. hakonesis, but some T. hakonensis harbored the metacercariae of Miyata type of Metagonimus with those of M. yokogawai.

• Applied Microscopy
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• v.40 no.1
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• pp.1-8
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• 2010

The ultrastructure of spermatogenesis and sperm in Chinese minnow, Rhynchocypris oxycephalus belonging to Leuciscinae was investigated by light and electron microscopes. The whitish testis was located between intestine and air bladder. The size of testis was major axis 2.3 cm, minor axis 6 mm. The testis contained numerous testicular cysts, and spermatogenesis was non-synchronized in these testicular cysts. In the case of spermatogonium, the nucleus was comparatively large ellipsoidal, and mitochondria showed a marked development. The size of primary spermatocyte was smaller than that of spermatogonia, and secondary spermatocyte was smaller than primary spermatocyte. The chromatin of spermatocyte was highly condensed according to their development. The nucleus with electron-dense was round shape. In spermiogenesis, flagella started to be formed and chromatin was more condensed. The mitochondria were rearranged in a middle piece. The sperm was formed by loss of cytoplasm. The head of mature sperm was a spherical shape and have not acrosome. The microtubules of flagella were arranged 9+2 structure. Also, the tail of sperm have not lateral fins.

• Applied Microscopy
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• v.39 no.3
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• pp.237-243
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• 2009

Chinese minnow, Rhynchocypris oxycephalus is a teleost belonging to Leuciscinae, Cyprinidae. The oogenesis and ultrastructure of egg envelope in Chinese minnow were investigated by light and electron microscopes. The ovary was of white yellowish and ellipsoidal shape with the major axis 30 mm and the minor axis 7mm. Cytoplasm of oogonia was basophilic and many nucleoli were located at inside of nuclear membrane. In primary oocytes, yolk vesicles were distributed only in the marginal area and egg envelope was not formed on the outside of an egg. In secondary oocytes, the egg envelope was formed and yolk vesicles in the cytoplasm were increased than the earlier stage. The basophilic substance of cytoplasm was changed to acidic. In case of matured egg, thickness of egg envelope and size of egg were increased. The yolk vesicles were changed to yolk mass in accordance with development. The outer surface of egg envelope was covered by microvilli-structures, and had a micropyle on the area of animal pole. Egg envelope consisted with 2 layers, an adhesive outer layer with microvilli-structures and fibrillar inner layer. In conclusion, the oogenesis of Chinese minnow was characterized by the increase in cell size, the formation and accumulation of yolk, and the decrease of basophilic substance in the cytoplasm. The oogenesis of Chinese minnow seems to share common patterns in Cyprinidae, but these ultrastructural unique characters of egg envelope can be utilized in taxonomy of teleost.