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A Systematic Study on the Ascidians from Cheju Island, Korea (제주도산 해초류(Ascidians)의 분류학적 연구)

  • Rho, Boon-Jo;Lee, Ji-Eun
    • Animal Systematics, Evolution and Diversity
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    • v.5 no.1
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    • pp.59-76
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    • 1989
  • In order to carry out a systematic study of ascidians in Cheju Island, the authors identified and classified specimens collected from 11 sites around Cheju Island from December 1 1969 to January 1989. Using the information gathered from this study as well as previous s studies, the authors prepared a detailed list of the ascidians of Cheju Island. A As a result of this study, the ascidians of Cheju Island are 50 species in 10 families. Among them, 3 species (Dideηmum apersum, Didemnum translucidum, Botrylloides perspicuum) had not previously been known to exist in Korean waters. Description and drawings of these three species are presented in this report. It was also discovered that ten of the fifty species are found only in the Cheju Island area. The fifty species recorded in the Cheju Island area account for 68% of the seventy three species recorded from all Korea. Classifying them by t the temperature of the water where they are found, the authors found the following: one cold water species (2% of the total), seven cold-temperate water species (14%), thirty eight warm-temperate water species (76%) and four tropical water species (8%)

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Comparison Between Phylogenetic Relationships Based on 18S rDNA Sequences and Growth by Salinity of Chlorella-like Species (Chlorophyta)

  • Lee, Hye-Jung;Hur, Sung-Bum
    • Fisheries and Aquatic Sciences
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    • v.15 no.2
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    • pp.125-135
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    • 2012
  • This study was carried out to understand the correlation between phylogenetic relationships based on 18S rDNA sequences and growth by salinity of Chlorella-like species. The 18S rDNA sequences of 71 Chlorella-like species which were mainly collected from Korean waters were analyzed. The 18S rDNA sequences of Chlorella-like species were divided into three groups (group A, B and C) and group B was further divided into three subgroups (subgroup B-1, B-2 and B-3). Thirty-seven Chlorella-like species in group A grew well at high salinity (32 psu) but the other groups grew well in freshwater. The sequence identities of the species in group A and B were 97.2-99.5%, but those of 6 species in group C ("Chlorella" saccharophila), which contained group I intron sequences region were 75.0-75.4%. Two representative species of each group were cultured at different salinities (0, 16 and 32 psu) to examine the correlation between the molecular phylogenetic groups and the phenotypic characteristics on cell growth and size by different salinities. The size of cell cultured at different salinities varied according to the species of each molecular phylogenetic group. The size of "Chlorella" saccharophila in group C was bigger and more obviously elliptical rather than that of the other Chlorella-like species. Considering the results on molecular and phenotypic characteristics, the group A and B belonged to Chlorellaceae, but group C was distinctly different from them.

Study of Freshwater Fish Fauna and Distribution of Introduced Species of Mankyeong River, Korea (만경강의 담수어류 및 외래어종의 분포)

  • Lee, Wan-Ok;Kim, Kyeong-Hwhan;Kim, Jong-Hwa;Hong, Kwan-Eui
    • Korean Journal of Ichthyology
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    • v.20 no.3
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    • pp.198-209
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    • 2008
  • During studies of the fish fauna and communities of Mankyeong River, which flows to the Yellow Sea, 14 families in 44 genera and 63 species of freshwater fishes were caught. Zacco platypus (27.7%) was the dominant species and Z. koreanus (11.3%) the subdominant species in this river. Twenty-three species of Korean endemic fishes appeared, and two of these, Pseudopungtungia nigra and Liobagrus obesus, represented endangered Korea species. Community structure of each branch stream was stable, showing appropriate dominant species: Z. koreanus in Jeonju Stream, Z. platypus in Kosan and Soyang Streams, and Carassius auratus in Mankyeong main stream. Three introduced species appeared: C. cuvieri, Micropterus salmoides, and Lepomis macrochirus. Among these introduced species, M. salmoides expanded its territory from midstream to downstream because of its strong carnivorous tendency and it favoring of lentic waters. This distribution of M. salmoides affected the number and distribution of small native freshwater fishes, especially those in the subfamily Acheilognathinae.

The Bird Diversity and Feature by the Habitat Environment in Gotjawal area, Jeju Island, the Republic of Korea (제주도 곶자왈 지역에서 서식 환경에 따른 조류 다양성 및 특징)

  • Kim, Eun-Mi;Kang, Chang-Wan;Choi, Hyung-Soon
    • Journal of Environmental Science International
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    • v.28 no.11
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    • pp.917-925
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    • 2019
  • All of the animals and the plants in ecosystem are intimately connected to one another and the changes of forests and surroundings affect directly wild animals. This study was conducted at Hangyeong-myeon Cheongsu-ri located in the western part of Jeju Island belonging to Hangyeong Andeok Gotjawal Zone and Jocheon-eup Seonheul-ri located in the eastern part of Jeju Island belonging to Jocheon Hamdeok Gotjawal Zone. The survey on advent of birds was carried out twice a month from January 2014 to December 2015. We divided habitat environments into three survey sites such as a forest, a shrub forest and a farmland. A total of 65 species and 4,802 individuals were observed during the survey period. In a forest, 36 species and 1,287 individuals were observed while A shrub forest had 40 species and 1,554 individuals. And in a farmland, 41 species and 1,961 individuals were observed. The only 10 species were observed in forest and the only 7 species in shrub forest and the only 10 species in farmland. The species diversity and the evenness of a farmland were the highest, and the species richness was the highest in a shrub forest, and the dominance of a forest was the highest among the three areas. The similarity index between a shurb forest and a farmland was high while that between a forest and a farmland was low. The similarity index related with breeding appeared that a forest and a farmland was different from each other.

A study on species composition and bycatch status of fishes by a three-side fyke net fisheries in Asanho Lake and Chungjuho Lake (아산호와 충주호의 삼각망에 의한 어획물 종 조성과 혼획 실태 연구)

  • Min Ah HEO;Heui Chen AN;Wan Ok LEE;Yong Beam PYEON;Seong Hun KIM
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.3
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    • pp.196-205
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    • 2023
  • This study investigated the species composition and bycatch status of fishes by fyke net between June and November 2020 in Asanho lake and Chungjuho lake. During the survey period, the catches in Asanho lake were identified as 2,931 individuals of 16 species from a total of six families and in Chungjuho lake were identified as 1,645 individuals of 14 species from a total of eight families. The dominant species in Asanho lake was Erythroculter erythropterus which accounted for 59.6% of the the total number of individuals and 40.5% of the total biomass caught. The dominant species in Chungjuho lake was Lepomis macrochirus which accounted for 48.2% of the the total number of individuals and Erythroculter erythropterus which accounted for 60.2% of the total biomass caught. The bycatch rates of non-commercial species in Asanho lake and Chungjuho lake were 77.0% and 82.6%, respectively. As a result of analyzing the frequency distribution of the total length of Carassius auratus and Siniperca scherzeri, which were the dominant species among commercial species, the bycatch rate of small individuals was 87.1%, and 42.7%, respectively.

Phytoplankton composition in intensive shrimp ponds in Bac Lieu province, Vietnam

  • Nguyen Thi Kim Lien;Phan Thi Cam Tu;Vo Nam Son;Huynh Truong Giang
    • Fisheries and Aquatic Sciences
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    • v.26 no.8
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    • pp.470-481
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    • 2023
  • Algal overgrowth in shrimp culture ponds can affect the quality of the aquatic environment, thereby adversely affecting the shrimp and causing economic losses. The objective of this study was to evaluate the variation in phytoplankton composition in intensive shrimp ponds in Bac Lieu province, Vietnam. Phytoplankton samples were collected in three black tiger shrimp (Penaeus monodon) ponds and three whiteleg shrimp (Litopenaeus vannamei) ponds. The collected data were analyzed using SPSS and canonical correlation analysis softwares. In total, 75 species of phytoplankton were recorded in black tiger shrimp ponds and 64 species in whiteleg shrimp ponds. Diatoms had the highest species diversity with 29-30 species (39%-47%), followed by green algae with 9-19 species (14%-25%); species numbers of other phyla varied from 5-12 (8%-16%). The total number of phytoplankton species throughout the study varied from 34-50 species. Algal density was relatively high and ranged from 497,091-2,229,500 ind./L and 1,301,134-2,237,758 ind./L in black tiger shrimp and whiteleg shrimp ponds, respectively. The diatom density tended to increase during the final stage of the production cycle in black tiger shrimp ponds. Blue-green algae and dinoflagellates also increased in abundance at the end of the cycle, which can affect shrimp growth. Diatoms were significantly positively correlated with pH, salinity, total ammonia nitrogen, and nitrate (NO3-) concentrations (p < 0.05). Blue-green algae and dinoflagellates were positively correlated with salinity, phosphate (PO43-), and NO3-. Algal species diversity was lower in the whiteleg shrimp ponds than in the black tiger shrimp ponds. Several dominant algal genera were recorded in the shrimp ponds, including Nannochloropsis, Gyrosigma, Chaetoceros, Alexandrium, and Microcystis. The results of this study provide basic data for further investigations, and they contribute to the management of algae in brackish-water shrimp ponds.

Bycatch reduction plan of offshore dredge in the western sea, Korea (서해안 근해형망 어업의 혼획저감 방안)

  • Sug-Tai KIM;Hyun-Young KIM
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.4
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    • pp.290-300
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    • 2023
  • This study aimed to identify the actual catch situation of offshore dredge gear which is newly regulated in the legislation. It's also conducted to identify the species composition, weight of the catch including the target species and incidental catches, and to provide the basic information necessary for the resource management of aquatic organisms caught by offshore dredge. During the investigation period (from September 2022 to May 2023), a total of 61 species appeared in the test operation sea of Boryeong, Chungcheongnam-do and Gunsan, Jeollabuk-do, with 31 species of fishes, 11 species of malacostraca, six species of gastropoda, five species of bivalvia, three species of cephalopoda, three species of asteroidea, one species each of asteroidea and holothuroidea appeared. According to the results of the test operation conducted in September and November 2022, the non-catch season of Atrina (Servatrina) pectinata, 1,203 shellfishes were caught out of 2,979 caught in number, showing a bycatch rate of 59.6%, and by weight, 157.9 kg of shellfish was caught out of the total catch of 448.4 kg, showing a bycatch rate of 64.8%. On the other hand, in February and May 2023, the catch season for Atrina (Servatrina) pectinata, 3,692 fishsells were caught out of the 4,232 catches in total, showing a bycatch rate of 12.8%, and by weight, 1,185.0 kg of shellfish was caught out of the total catch of 1,293.2 kg, showing an 8.3% bycatch rate.

Newly Developed Microsatellite Markers of Mystus nemurus Tested for Cross-Species Amplification in Two Distantly Related Aquacultured Catfish Species

  • Chan, S.C.;Tan, S.G.;Siraj, S.S.;Yusoff, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.11
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    • pp.1513-1518
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    • 2005
  • The work reported here is an attempt to explore the possibility of DNA microsatellite loci transfer (cross-species amplification) to other economically important aquacultured catfish species other than its source species. A total of 25 new microsatellite loci developed for riverine catfish, Mystus nemurus were successfully cross-amplified in two distantly related catfish species within the suborder Siluroidei. Five out of the 19 loci that successfully cross-amplified in Pangasius micronemus were polymorphic, while for Clarias batrachus, cross-amplification was successful using 17 polymorphic loci. The observed heterozygosities were high for all the three catfishes. The results indicated that microsatellite loci could be as polymorphic in non-source species as in the source species.

Mycophagous Gall Midges (Diptera: Cecidomyiidae) in Korea: Newly Recorded Species with Discussion on Four Years of Taxonomic Inventory

  • Ham, Daseul;Jaschhof, Mathias;Bae, Yeon Jae
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.1
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    • pp.60-77
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    • 2020
  • Cecidomyiidae (Diptera) consists of six subfamilies, which are divided into three groups according to larval ecological habits (phytophagous, mycophagous, and zoophagous). The five basal subfamilies of Cecidomyiidae consist entirely of mycophagous species, with approximately 1500 species described worldwide and 29 previously known to occur in Korea. In this study, 37 named species (1 Lestremiinae, 29 Micromyinae, 4 Winnertziinae, and 3 Porricondylinae species) are newly reported from South Korea. We excluded Lestremia yasukunii Shinji from the list of Korean mycophagous cecidomyiids as it is a nomen nudum. Therefore, we herein officially recognize 65 species, 30 genera, and four subfamilies for the Korean mycophagous cecidomyiid fauna. We also provide diagnoses and photographs to aid species identification and discussion on the four years of gall midge taxonomic inventory in South Korea.