• Korean Journal of Ichthyology
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• v.25 no.1
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• pp.38-41
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• 2013

A deep-dwelling goby, Obliquogobius yamadai, was described as the first record from Korea based on three specimens (30.3~47.0 mm SL) collected from the southern sea off Jeju Island. The species is characterized by having I, 9 second dorsal fin rays, scaled lateral side of nape, smaller head with large eye, and asymmetrical caudal fin dorsoventrally as well as about nine yellowish bars on body side. A new Korean name, "Gip-eun-ba-da-no-ran-ddi-mang-dug", is proposed for the species.

• The Korean Journal of Zoology
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• v.33 no.2
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• pp.238-240
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• 1990

A gobjoid fish, Pierogobius zacalies is described from three spedmens colleded in Songjong-dong, Pusan-si, on February 10, 1989. This Is the first definItive record in Korean waters. This fish is disdnguished from the other species of the genus Pierogobius by the combinadon of the following charaders: lateral-line scales > 113, soft dorsal fin rays VIII, i-24-25, soft anal fin rays i-24-25, and 5 dark-brown vertical broad band on the body. "Dasotdonggal-- mang-dug is proposed as Korean name of this species.cies.

• Applied Microscopy
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• v.52
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• pp.8.1-8.7
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• 2022

The Korean trident goby, Tridentiger brevispinis, lives in adverse habitats that can easily become hypoxic due to low precipitation, regional dry periods, and high amounts of solar radiation. Histological and morphometric studies revealed the goby's specialized skin (35.4-150.0㎛ in thickness), consisting of an epidermis and dermis. The thicker epidermis comprises an outermost surface layer (having taste buds, stratified fattened cells, mucous cells, pigment cells, and stratified polygonal cells), middle layer (having stratified polygonal cells), and stratum germinativum (stratified columnar cells). In particular, the dermis has scales, well-developed vascularization, and a few blood capillaries just above the basement membrane, and a reduced diffusion distance was present in the lateral body. Consequently, adaptations such as thicker epidermis, well-developed vascularization, few blood capillaries, and a reduced diffusion distance may provide cutaneous respiration for survival in poorly oxygenated water during the periodic dry season.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.1
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• pp.37-46
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• 2024

This study was conducted to provide the basic information on environment effects on appearance of ichthyoplankton in the Yeongsan River Estuary in Spring and Summer from 2018 to 2020. Data were obtain from the database of 'Coastal Ecosystem' in "National Survey of Marine Ecosystem." Among the abundance ichthyoplankton species, the Gobiidae spp. dominated, accounting for 85% of the total abundances with the secondary dominant species being the Parablennius yatabei, representing 3% of the abundances. Cluster analysis results revealed a composition differentiated between spring and summer. The Yeongsan River Estuary is known to be significantly influenced by the opening and closing of estuarine gates. In this study, the fluctuation in the number of occurrence groups and abundance among the years and season is attributed to the phenomenon of high water temperature period and the freshwater discharge.

• Korean Journal of Ichthyology
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• v.13 no.2
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• pp.136-142
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• 2001

The ichthyoplankton were sampled during six different months (January, March, May, July, September and November 1998) to study seasonal variation and species composition of the ichthyoplankton in Sunchon Bay. During the study, fish eggs collected in May and July were identified as belonging to 4 species. The most of dominant species Engraulis japonicus accounted for 54.1% of the total fish eggs, followed by Leiognathus nuchalis (21.8%), Ilisha elongata (12.7%) and Konosirus punctatus (11.4%). The collected larvae and juveniles were identified into 12 taxa. 11 of which were identified to species level, and 1 taxa identif ied only to family level, respectively. The dominant species, Ilisha elongata, accounted for 48.9% of the total larvae and juveniles: it was followed by Pholis nebulosa at 31.8%. A species of Gobiidae and Thryssa hamiltoni accounted for 15.8% and 2.2% of the total, respectively. The 4 taxa constituted 98.7% of the total collected larvae and juveniles.

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.295-303
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• 2005

The sexual dimorphism and intra sexual dimorphism in males of Rhinogobius brunneus were investigated at Jiam stream, a tributary of the Bukhan river from May, 2005. The frequency distributions in standard length were similar for the females and maleLs, but maleSs were smaller than the females and maleLs. The ratio of MaleL (N=79) to males (N=79) was 1 : 0.46. The comparison between female (N=79) and maleL (N=79) gave significant differences (P<0.05) in 18 morphometric characteristics (SNL, AHD, PHD, ML, DL, MW, AHW, IFW, PHW, ED, HL, FDFL, SDFB, CFL, AFB, VFL, PFL, PFB) and 12 characteristics (SNL, AHD, ML, DL, MW, AHW, IFW, PHW, HL, FDFI, CFL, PFB) (P<0.001). Eight morphometric characteristics (SNL, ML, DL, MW, HL, CFL, VFL, PFL) in female (N=36) and males (N=36) had significant differences (P<0.05) and three characteristics (ML, DL, HL) had very significant differences (P<0.001). Eleven characteristics (SNL, AHD, PHD, ML, DL, MW, AHW, IFW, PHW, HL, FDFL) were significantly different in maleL (N=36) and males (N=36) (P<0.05) and six (ML, DL, MW, AHW, HL, FDFL) were very significantly different (P<0.001).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.230-243
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• 1984

Larvae of fishes were collected at 26 stations in the Korea Strait, by horizontal towings using the fish larval net (Norpac) in the surface layer and by oblique towings using Isaac-Kid mid-water trawl in the mid-water layer in summer (July) and in autumn (November), in 1983. The towing speed was 1.5 knots. Of the larval fish examined, 3,529 individuals were identified to generic and specific levels. They belong to 27 families, consisting of 38 species in 37 genera. Unidentified were 114 specimens. The most abundant species was Engraulis japonica which occupied $88.5\%$ of the whole 3,645 individuals. Diaphus sp. took the second place with 50 individuals ($l.3\%$). Seasonally abundant species were in the order of Engraulis japonica, a Gobid, Trichiurus lepturus, and Diaphus sp. in summer, and in the order of Diaphus sp., Engraxlis japonica, Bothus sp., and a Ophichthid in autumn. Of these larvae, Engraulis japonica and Diaphus sp. continuously appeared from summer to Autumn. Champsodon sp., Diaphus sp. and Synagrops philippinensis were unrecorded species in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.907-916
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• 2013

The aim of this study was to compare community structure of larval fish species in the northern East China Sea during normal meteorological conditions in autumn 2009, during the El Ni$\tilde{n}$o period in 2009-2010, and during the La Nina period in 2010. Fifty taxa were recorded during the study period; the most dominant species were Benthosema pterotum and Gobiidae spp. In October 2008 during the normal period, warm water from the Tsushima Warm Current (TWC) intruded more into the surface and middle layers, and cold water affected by the Yellow Sea Cold Water (YSCW) intruded into the bottom layer. In October 2009 during the El Ni$\tilde{n}$o period, intrusion of the China Coastal Water (CCW), which has low salinity (<32.2 psu), was more apparent than intrusion of the TWC or YSCW. In October 2010 during the La Nina period, intrusion of the TWC and CCW was relatively weak, resulting in the lowest temperature and highest salinity observed during the study period in the eastern part of the study area. Hierarchical cluster, one-way ANOSIM (analysis of similarities), and SIMPER (similarity-percentages procedure) analyses provided two main results. First, the abundance of the most dominant larval fish species in autumn of the normal period was greater than that in autumn of the El Ni$\tilde{n}$o/La Nina periods, resulting in a significant difference in ichthyoplankton community structure between the periods. The abundance of Benthosema pterotum increased in the normal period, possibly influenced by the intrusion of cold water from the YSCW; the abundance of species residing in Korean waters (e.g., Gobiidae spp.) probably decreased during the El Ni$\tilde{n}$o/La Nina periods. The second finding was that the abundance of subtropical larval fish in autumn of the normal period was generally larger than that during autumn of the El Ni$\tilde{n}$o/La Nina periods. This could have been induced by the stronger intrusion of warm water from the TWC during the normal period. Although differences in oceanographic conditions between El Ni$\tilde{n}$o and La Nina periods were observed, the differences in ichthyoplankton community structure between the two periods were not significant.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.730-744
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• 2016

In this study, fish fauna and stream characteristics were surveyed from June to October of 2014 in 31 sites of 23 small streams of Namhae Island. During the study period, 38 species belonging to 30 genera under 13 families were collected. Cyprinidae and Gobiidae fish occupied 28.9% (11 species) and Cobitidae fish accounted for 10.5% (4 species). The dominant family was Cyprinidae, and the most dominant species was Zacco koreanus with 30.3% (1,089 individuals) of the total. Eight species (33.8%) such as Zacco koreanus, Squalidus gracilis majimae, Coreoleuciscus splendidus, Pseudobagrus koreanus, Iksookimia hugowolfeld, Iksookimia longicorpa, Silurus microdorsalis and Liobagrus mediadiposalis were Korean endemic and one species of Micropterus salmoides was exotic. According to the analysis of the community based on the diversity, evenness and richness indices, fish community seems to be more stable in the S7. The small streams were classified into three types of steep mountainous, mountainous-flatland, and flat land streams, and their types were categorized by their features of stream width, water depth, bottom substrate, riparian vegetation, and land use patterns. Principal component analysis based on species abundance classified fish communities into three main groups according to human impact and land-use pattern change. These results suggest that fish community structures were primary affected by the longitudinal environmental changes and these were modified by the habitat condition in accordance with the land use pattern change in the small streams.

• Korean Journal of Ichthyology
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• v.28 no.2
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• pp.100-109
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• 2016

Species composition and distribution characteristics of fish were determined by monthly underwater visual census from September. 2013 to August, 2014 at Yeongunri off Tongyeong, Korea. The study area was divided into five habitat types by depth and substrate: (1) sand bottom as depth of 0~2 m, (2) seagrass bed of 2~5 m, (3) rocky outcrop of 0~2 m, (4) rocky bottom of 2~5 m, (5) sandy mud bottom of 5~8 m. A total of 1,673 individuals belonging to 43 species in 26 families were recorded during the study period. The number of species tended to decrease after October, 2013 and increase from March, 2014 showing the highest number in October (autumn), and lowest in January (winter). In terms of the number of species, Gobiidae was the most dominant family (7 species), followed by Scorpaenidae (4 species). Embiotocidae was the most abundant (26.1% in total number of individuals), followed by Scorpaenidae (19.9%) and Gobiidae (19.3%). The dominant species were Sebastes inermis (19.2%), Ditrema temminckii (13.1%), and Neoditrema ransonnetii (12.9%). The number of species and abundance were relatively high at the depth between 2 and 5 m on seagrass bed and rocky bottom, whereas they were lower at the depth between 0 and 2 m on the sand bottom, suggesting that seagrass beds and rocky bottoms provided the diverse habitats for various fish species in this sea.