• 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 Ichthyology
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• v.5 no.1
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• pp.96-112
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• 1993

The morphological characteristics of chum salmon Oncorhynchus keta, masou salmon. Oncorhynchus masou and rainbow trout, Oncorhynchus mykiss in Korea were studied from 1989 to 1990. It was found that 13 factors of the female and 11 factors of the male in body form, number of pyloric ceaca and gill rakers has significant specific differences. There were some differences among species in the ratios of body depth, caudal peduncle depth, dorsal fin length and anal fin length to standard length (PBL), and snout length, eye diameter, upper jaw length, and cheek to head length. In the ratio of head length to fork length of the male, chum salmon showed the highest(24.7%) value and rainbow trout the lowest(21.6%). No difference was found in the female. It was proved that number of vertebrae, gill rakers, pyloric ceaca and lateral line scales were useful taxonomical characteristics of the salmon species. In particular, the ratio of eye diameter (ED) to head length (HL) appeared to be a new taxonomic criterion for the salmons in Korean waters.

• 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 Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.404-408
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• 1999

To analyze the possibility for the genetic improvement at the early period at 60 days of age in tilapia, Oreochromis niloticus. Genetic parameters on eight traits, total length (TL), standrad length (SL), head length (HL), body depth (BD), body height at the origin of dorsal fin (BH1), length from the origin of dorsal fin to the origin of dorsal fin (BH2), snout length (SNL), and body weight (BW), were estimated by sib analysis. Heritabilities estimated from sire, dam and full-sib components were moderately high in all metric traits, ranged 0.08$\~$0.70, 0.22$\~$0.41 and 0.18$\~$0.55, respectively. Those of SL from sire, dam, and full-sib component were estimated as 0.13, 0.22, and 0.18, respectively, Besides BH1, BH2 also showed high heritabilities, $h^2_s$ (0.08), $h^2_d$ (0.38) and $h^2_{s+d}$ (0.23), indicating that it would be a new production-related metric trait for selection. Among the metric traits, phenotypic and genetic correlation coefficients were ranged from 0,86 to 0.97 and from 0.90 to 0.99, respectively. Thus, genetic improvement would be possible at the early growth rate by the individual selection in tilapia.

• Korean Journal of Ichthyology
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• v.1 no.1_2
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• pp.54-63
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• 1989

Morphological variation of the crusian carp, Carassius auratus, from Yongnam area in Korea was examined. In morphometric and meristic characters, mean values were different slightly among the polulations, whereas the range of variation was overlapped largely. In the present examination the number of spines in dorsal fin were 4-6. The majority of individuals appeared to be similar to Carassius auratus langsdorfii from Japan, but some individuals were quite different from them in having 66-83 gill rakers.

• Korean Journal of Ichthyology
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• v.10 no.2
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• pp.250-259
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• 1998

This study was carried out to reveal the taxonomic status of the two mullets, Chelon affinis and Chelon haematocheilus from Korea by comparison of their morphological characteristics. Chelan affinis, occurred in the southern coastal area, is a distinct species characterized by having a keel on the middorsal line in front of the spinous dorsal fin. However, Chelon haematocheilus, found in the all coastal areas of Korea excluding Cheju island is easily distinguished from the former in having the deep flat head. By comparison of five groups of Chelan haematocheilus, Kunsan group is slightly differed from others in the height of anal fin and caudal peduncle length. Although Chelon affinis is similar with Chelan haematocheilus in the view of meristic characters, they are distinguished from each other in the number of pyloric caeca and lateral line scales.

• Korean Journal of Ichthyology
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• v.4 no.2
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• pp.1-25
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• 1992

Taxonomic study of the five species (Acanthogobius elongata, A. flavimanus, A. lactipes, A. luridus and Synechogobius) from Korea was carried out based on morphometric, cephalic sensory canal and ecological characters. Taxonomic revision and classificational keys are provided. Synechogobius hasta is easily distinguished from four species of the genus Acanthogobius in eleven characters, i. e., the number of dorsal and anal fin rays, the transverse scales, the vertebral numbers, the formula of interneural spine of the first dorsal fin, the number of interhemal spine anterior to the first hemal spine, the number of epipleural and pleurals, the ratio of caudal peduncle length, the ratio of caudal peduncle depth and the regular variations in the ratio of body parts with the body length. In the genus Acanthobobius, A. elongata is distinguished from other 3 congeneric species in the ratio of body parts and the oculoscapular sensory canal. Moreover, A. flavimanus differs from other 3 congeneric species in the lateral scales, the transverse scales, the number of predorsal scales, the vertebral number, the number of epipleural and pleurals. Sensory papillae rows of S. hasta is not similar that of the genus Acanthogobius in having a singular sensroy papillae rows. A. elongata has no oculoscapular sensory canal D and A. flavimanus has transverse sensory papillae in cheek, and these are one of the unique characters distinguished form other congeneric species. In the spawning period inferred from gonadosomatic index, A. elongata varied from late March to late June ; A. flavimanus, January to April ; A. lactipes, May to September ; A. luridus, early May to early July and S. hasta, early March to early May.

• Korean Journal of Ichthyology
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• v.10 no.2
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• pp.216-230
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• 1998

The taxonomic review of the family Platycephalidae from Korea was made based on the morphological characteristics of specimens collected in the Korean coasts from December 1987 to April 1998. The family Platycephalidae from Korea was classified into 10 species belonging to 7 genera: Onigocia macrolepis, O. spinosa, Rogadius asper, Suggrundus meerdervoorti, lnegocia japonica, I. guttata, Cociella crocodila, Ratabulus megacephalus, Platycephalus indicus and Platycephalus sp. Of them, Onigocia macrolepis was recorded for the first time in Korea and Platycephalus sp. was demanded to recheck its taxonomic position comparing with other Asian specimens in future. A new key to the genera and species of the family Platycephalidae from Korea was reported, with description of their morphological characteristics and distribution.

• Korean Journal of Ichthyology
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• v.22 no.1
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• pp.65-77
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• 2010

To use the precise scientific name of the genus Gymnogobius from Korea, a taxonomic review of the genus Gymnogobius was made based on specimens collected in streams and estuaries of Korea from 1982 to 2007. The genus Gymnogobius in Korea includes 7 species: Gymnogobius breunigii (Steindachner), G. heptacanthus (Hilgendorf), G. macrognathos (Bleeker), G. mororanus (Jordan and Snyder), G. opperiens Stevenson, G. petschiliensis (Rendahl), G. urotaenia (Higendorf). A key to species of the genus Gymnogobius from Korea is provided, with description of their morphological characteristics and their distribution.

• The Korean Journal of Zoology
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• v.32 no.1
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• pp.22-33
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• 1989

Comparison of morphological characters and development of eggs and larvae of two bitterlings, Acheilognathus limbata and A. signifer from Korea were observed and discussed taxonomically. A. signifer differs from A. limbata by the color pattern of dorsal and anal fin ray of male, egg form and the length of ovipositor of female. Although two species are overlapping each other in some morphometric characters, there is a great difference between the two in the multivariate analysis of 15 morphological characters of five comparative populations. These results indicate that A. limbata and A. signifer are two independent allopatric sibling species in Korea.