• Korean Journal of Ichthyology
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• v.21 no.2
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• pp.67-75
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• 2009

Morphological and genetic variation of Cottus populations in Korea were compared to each other in the watershed. Morphological variation was analyzed by meristic and morphometric characters, and by fertilized egg sizes. Genetic variation was assessed by amplified fragment length polymorphism (AFLP) fingerprinting. Cottus koreanus populations of rivers and streams running towards the eastern coasts of the Korean Peninsula were significantly different in morphometric characters from populations in rivers and streams running towards the western and southern coasts of the Korean Peninsula, but did not differ in meristric characters and fertilized egg sizes. Cottus populations in the upper streams-Yangyangnamadae Stream, Jusu Stream and Samcheogosip Stream-were the same in meristic and genetic characters. However, the Cottus sp. population from Baebong Stream is related to C. hangiongensis in meristic characteristics and to C. koreanus in the morphometric characteristics of length of the ventral fin ray and in the fertilized egg size. Pairwise genetic distances assessed by the AFLP method among C. koreanus populations were in the range of 0.110 to 0.221. Genetic distances between C. hangiongensis and C. koreanus populations varied from 0.542 to 0.621, and those between the Cottus sp. population of Baebong Stream and C. koreanus populations from 0.222 to 0.304. The result of the UPGMA dendrogram shows the Cottus sp. population of Baebong Stream was clearly separated of other C. koreanus populations.

• Korean Journal of Ichthyology
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• v.34 no.4
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• pp.277-287
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• 2022

Two sculpin specimens (79.3~100.8 mm standard length) were collected from the upper reach of Deokdongcheon Stream, a tributary of the Hyeongsangang River, in Korea. They were identified as Cottus pollux by characteristics such as the absence of palatine teeth, 12~13 unbranched pectoral fin rays, pelvic fins without obvious bands or spots, and the absence of a blackish band on the head or anterior part of the body. A phylogenetic analysis based on the nuclear ITS1 gene and mitochondrial cytb gene indicated that the specimens formed a clade with Japanese C. pollux, supporting the morphological species identification. We propose a new Korean name for the species: "Min-mu-nui-dug-jung-gae"

• Korean Journal of Ichthyology
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• v.8 no.1
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• pp.14-21
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• 1996

The sexual dimorphism of river sculpin (Cottus poecilopus Heckel) was investigated samples were collected from the Chiak stream from January 1993 to April 1994. Sexual dimorphism in body size and some morphological characteristics were observed in this species ; males were larger in size and had a larger mouth, anal fin, ventral fin and pevic fin than females. Males have a genital papilla and nuptial color, but females do not. Females may mate preferentially with large males. Larger males could be superior in nest defense and fanning of eggs to smaller ones, thus resulting in higher survival of eggs. Similary, the larger mouth in males could be advantageous in acquiring and defending their nests. Such sexual dimorphism in this species may reflect to outcome of sexual selection.

• Korean Journal of Ichthyology
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• v.20 no.4
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• pp.279-284
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• 2008

The feeding ecology of endangered Cottus hangiongensis was studied in the Hosan stream from September 2006 to August 2007 by collecting them seasonally. The stomach contents of C. hangiongensis consisted mainly of aquatic insects and Nematoda, small fish, fish eggs, snails (Semisulcospira libertina), and small stones were also observed. The main aquatic insects in the order of relative importance were Diptera, Trichoptera, Ephemeroptera and Plecoptera. The most important prey items were Chironomidae sp.1 and Hydropsyche kozhantschikovi. Change in the main prey organisms by season were Trichoptera in the spring and the summer, Diptera in the autumn, and Plecoptera in the winter by ratio of dry weight.

• Korean Journal of Ichthyology
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• v.18 no.3
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• pp.155-162
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• 2006

The chromosome numbers of five species in two families of Korea are investigated: Odontobutis platycephala, O. interrupta, and O. obscura in Odontobutidae, and Cottus koreanus and C. hangiongensis in Cottidae. In Odontobutis species, the three species showed the diploid chromosome number, 2n=44 (NF=44) telocentric chromosomes. In Cottus species, the mitotic chromosomes from 24 groups with two chromosomes each indicated that it is a diploid. The karyotype of C. koreanus and C. hangiongensis is 2n=48 and NF=52. These species is the first report on the chromosomes and the karyotype analysis except O. platycephala. Our findings provide cytotaxonomic evidence for the species distinctness of these five species whose descriptions were based primarily on external morphology.

• Korean Journal of Ichthyology
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• v.30 no.3
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• pp.155-160
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• 2018

The distribution aspect and extinction threat evaluation of the endangered species, Cottus hangiongensis were investigated from 2011 to 2017 in Korea for this study. The distribution reports of C. hangiongensis were divided into 1954~1985, 1981~2003, 2004~2012, and 2011~2017. The number of habited streams decreased gradually to 30, 24, 10, and 19 streams, respectively. In this study (2011~2017), C. hangiongensis was newly found in two streams (Ayajincheon and Chuksancheon), but 15 streams that appeared in the past are not in this study. The main habitat of C. hangiongensis was the downstream riffle of clean water with fast velocity and cobble-boulder bottoms. Given this evidence as noted for more than a 30% reduction in population after 2003, due to construction wear, river work and the qualitative decline of the habitat, C. hangiongensis is now considered to be Vulnerable (VU A2ac) based on the IUCN Red List categories and criteria.

• Korean Journal of Ichthyology
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• v.7 no.2
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• pp.128-134
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• 1995

In order to study the taxonomic status of Cottus species from Korea, 19 morphological characters, egg number and size and hatched juvenile form in C. poecilopus and C. hangionsis were compared. The two species of C. poecilopus and C. hangionsis overlap each other in morphometric characters mostly, but snout length, caudal peduncle length and pectoral fin ray number were distinguished between them. Moreover the C. poecilopus and C. hangionsis specimens were differ from each other in the number of egg and size. The newly hatched juvenile form of C. hangiongensis produced many small eggs from which pelagic larvae were formed. In contrast, C. poecilopus produced well - developed juveniles. Two species have distinctly different life - cycles ; amphidromous for C. hangionsis and fluvial land - locked for C. poecilopus.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.1
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• pp.46-53
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• 2010

Spawning behavior and early life history of the tuman river sculpin, Cottus hangiongensis were studied in the laboratory and in the field at Wangpi Stream, Gyeongsangbuk-do, Korea, from January to December, 2007. The spawning ground was in the lower Wangpi Stream, which is a shallow region about 40cm or less in depth. During the spawning period, from March to April, mature males made nest cavities under stone 10 which they led a gravid female. The male and female then turned upside down, and spawning and fertilization occurred onto the ceiling of the nest cavity. After spawning, the male chased the female from the nest and mated with several other females. Fertilized eggs were spherical in shape, demersal, adhesive, transparent and yellow in color, measuring 1.86 mm (1.79~1.93 mm) in diameter. A mean of 17(12~22) various-sized oil globules were counted in the yolk. Granular materials formed a mass in the yolk. Fertilized eggs hatched at 256 hrs, 10 minutes after the morula stage under water temperature of $15.0{\sim}18.0^{\circ}C$. Newly hatched larvae 9.34 mm (9.02~9.69 mm. n=10) in total length (TL) had a large yolk At 14 days after hatching, larvae 11.40 mm (11.07~11.72 mm, n=10) in TL transformed to the postlarval stage. At 41 days after hatching, postlarvae of 18.42 mm (17.31~18.62 mm, n=10) in TL had reached the juvenile stage. The result of this study indicate that Cottus hangiongensis has the spawning ground in the lower stream and the amphidromous life history which is the different from that of Cottus poecilopus.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1998.06a
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• pp.89.1-90
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• 1998

• Korean Journal of Ecology and Environment
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• v.42 no.2
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• pp.145-152
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• 2009

The fish community was investigated from March to October 2007 in Gwangneung Arboretum. During the survey period, 22 species belonging to 9 families were collected. Among them, one species (Coitus koreanus) was classified as an endangered species in Korea, and exotic fish was Micropterus salmoides. Nine species (40.9%) were endemic species of Korea. Dominant species was R. oxycephalus (St. 1) and Z. platypus (St. 2-7). According to analysis of community based on the diversity, evenness and richness indices, fish community seems to be more stable in the St. 3. The distributions of Silurus microdorsalis, Cottus koreanus and Odontobutis platycephala were confined to the Bongseonsa Stream in the Wangsuk Stream watershed. When our data were compared with the previous data (1932), 17 species were not sampled, but 7 species could new taxa fiend its existence at the Bongseonsa Stream. We believe that Hemibarbus mylodon, Acheilognathus signifer and Zacco koreanus disappeared in the Wangsuk Stream watershed and A. signifer and Z. koreanus need to be restored at the Bongseonsa Stream.