• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.3
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• pp.145-149
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• 1988

The effects of temperatures, salinities and diets on the larvae of the fresh water prawn, Macrobrchium koreana were studied. Survival rates were decreased with increasing salinity concentrations, and the second larval stages were almost died in 48 hours in over $40\%$ sea weter$(13.7\%)$. The intermolt duration of the each stage were shortend with increasing water temperature, and the optimum temperatures of the larvae were from $22^{\circ}C\~26^{\circ}C$ The larvae fed with the meat of Tapes japonicus showed the highest survival rate. When the larvae were fed with the eggyolk powder, all the lauvae died before fourth zoea. Under starved condition moltings were continued up to third zoea.

• The Korean Journal of Zoology
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• v.33 no.2
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• pp.200-216
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• 1990

The complete larval development of Scopimera bitympana Shen was descdbed and mustrated from the larvae reared in the lahoratory. S bItympana had five, or occasionally six, zoeal and one megalopal stages. At $25^{\circ}C$, the megalopa and the first crab instar were attained in 24 and 38 days (31 and 48 days in six zoeal series) after hatching respectively. S.bitympana zoeae can be distinguished from other described zoeae in the genus by the toothed carapace spines and the telson with a dorsal and two ventral spines. Megalopa of this species can be distinguished from other ScopimeTa spedes by the feature of carapace. Other minor morphological features of S. bitympana larvae are compared to the previous descripdons of larvae of the genus and the morphological differences are briefly discussed.

• The Korean Journal of Malacology
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• v.27 no.4
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• pp.359-369
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• 2011

Twelve species of food microalgae were investigated to clarify the digestion index of Crassostrea gigas larvae using epifluorescence microscopy to choose an appropriate diet for artificial seed production in hatchery. An experiment was conducted using 1 (D shaped stage), 4 (Early umbo stage), 8 (umbo stage) and 12 (Full grown stage) days old larvae. larvae were stocked in 1 L flasks at 5 individuals/mL and fed $10{\times}10^4$ algal cells/mL of each species individually. Prior to larvae were fed for 3 h and then were observed under the microscope to detect ingestion; larvae were then sieved and replaced in 1 L flasks containing filtered seawater and were observed after 3, 5 and 8 h to analyse the digestion index. Values of digestion indices were specific for each alga. No evidence for the ingestion of Thalassiosira weissflogii was evident at all larval development stages tested. Digestion indices of others microalgae were 0.8-99.7% at 4 stage of larval development stages: Chlorella ellipsoidea (0.8-5.4%), Nannochloris oculata (1.4-5.0%), Isochrysis galbana (99.1-99.5%), Pavlova lutheri (99.1-99.5%), I. aff. galbana (99.4-99.5%), Cheatoceros calcitrans (0.0-99.2%), C. gracilis (0.0-99.7%), C. simplex (0.0-95.9%), Phaeodactylum tricornutum (0.0-99.6%), Tetraselmis tetrathele (0.0-99.7%) and Dunaliella tertiolecta (0.0-99.6%), respectively. Therefore, it is assumed that food microalgae showing the high digestion such as I. galbana should be supplied to the early umbo stage larvae, and then after the umbo larval stage, the mixed microalgae with diatoms and light green algae should be supplied to the full grown stage larvae to increase the digestion of their larvae.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.4
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• pp.206-216
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• 1988

In order to set up a predictive model for effective spat collection of pen shell, Atrina (Servatrina) pectinata, the survival rate and time required at each developmental stage of drifting larvae were surveyed during the period from June 8 to October 16 in 1986 at the Yongku inlet Chilchon Is., Chinhae Bay, the southern part of Korea. And also the experiments of spat collection were carried out In Yongku inlet during the period from July 6 to November 23 in 1987 and In Yoja Bay during the period from July 9 in 1987 to February 15 in 1588. The advent of D-shape larvae ca. $135\times144um $ long had three peaks in that area: August 1, 12 and 25. Umbo shape larvae ca. $300\times317um$ and full grown larvae ca. $455\times450um$ long also sowed three peaks: August 9, August 22 and September 4 for the former, and August 23, September 3 and September 16 for the latter. Nine to ten days was required for D-shape larvae to develop to umbo shape larvae. The instantaneous survival rate was 0.94 with a total survival rate if $54\%$ at this intermorphological stage. The required time of umbo to full grown larvae varied from twelve to fourteen days with a instantaneous survival rate of 0.88 and total survival rate of $19\%$. Twenty-two to twenty-three days was required for each group of the D-shape larvae to reach a fullgrown stage, and their total survival rate was $10\%$ during this developmental period. The number of the spat attached to the spat collector is 0.16 inds. per $m^2$ vertical spat collector in Yongku inlet and 0.48 inds. per $m^2$ horizontal spat collector in Yoja Bay. The average shell length of spat attached was $0.51({\pm}0.15)\;mm$ on September $27,\;38.52({\pm}6.98)\;mm$ on November 21 in 1987 and $49.00({\pm}10.77)mm$ on February 15 in 1988.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.384-385
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• 2003

대부분의 해산무척추동물의 번식은 정자와 난을 해수중으로 내보내어 체외수정을 통해 부유유생의 시기를 거치는 반면 일부 저서성 무척추동물에서는 체내유생발생 또는 보육보호의 번식습성을 지닌 종들의 생태학적 연구가 보고되고 있다(Strathmann and Strathmann, 1982; Olive, 1985). 이와 같은 번식습성의 차이는 서로 다른 서식환경에 따른 번식전략의 적응기작이라고 보고되고 있다(Levin ＆ B.idges, 1995). (중략)

• Animal Systematics, Evolution and Diversity
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• v.10 no.2
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• pp.199-205
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• 1994

In the life cycle of Coryne pusilla Gaertner, a medusa is lacking and the planula larvae represent the only known dispersive stage. The planula larvae crawled on the surface of culture vessel for about 21 hours after release, and settle down and start metamprohosis.

• Animal Systematics, Evolution and Diversity
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• v.2 no.2
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• pp.79-87
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• 1986

한국산 산호충류의 계통분류학적 연구의 일환으로 1970년부터 1985년까지 한국 황해 연안에있는 군락지와 흑산도에서 채집된 실꽃말미잘( Cerianthus filiformis)을 동정한 결과 한국미기록종으로 밝혀졌다. 1985년 4월에 채집된 개체는 몸속에 플라눌라 유생을 지니고 있었으며, 이들은 다양한 자포를 약간 갖고 있었고, 몸밖으로 나온 플라눌라 유생에서는 보다 분화된 자포를 갖고 있었다. 특히 성체에서는 체벽에 있는 자포 중 ptychocyst가 처고형성에 지주 역할을 함을 볼 수 있었다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.459-460
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• 2001

게류의 유생에 관한 수온, 염분 및 먹 이에 관한 연구들의 대부분은 유생의 각 영기에 따른 형태적 특징 등을 중심으로 한 것이며 여러 종류의 먹이를 공급하여 그 효과를 다양하게 조사한 연구는 찾아 보기 어려웠다. 한편, 본종의 자원조성과 종묘생산을 위해서는 먹이에 대한 기초조사가 다양하게 이루어 져야 할 것으로 생각되어 본 연구팀에서 조사하여 발표한 연구결과를 기초로 하여 여러 종류의 자연 및 인공 먹이를 공급하여 여러 가지 먹이에 대한 섭이효과를 조사하였다. (중략)

• The Korean Journal of Zoology
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• v.39 no.1
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• pp.106-114
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• 1996

Zoeae of Alpheus euplirosyne rlchardsoni Valdwyne, 1971 reared in the laboratory are described and Illustrated The culture was carded out under the laboratory condition with the photoperiod l4hr light and lOhr darkness and salinity of 33.3$\textperthousand$ at 25$^{\circ}$C. This species exhibits extended development on the egg size just before hatching and on the length of the first zoea. The morphological differences between the first zoea of this species and those of five other species in the same genus are discussed.

• Korean Journal of Environment and Ecology
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• v.26 no.3
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• pp.342-347
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• 2012

This study was conducted to demonstrate the relationship between experience of cannibalism and difference of phenotype in the Korean salamander Hynobius leechii from March to April 2011. We examined whether the different polyphenism of larval salamander is induced as a result of indirect cannibalism in early life cycle. We divided into two groups(one group continuously exposed to the indirect cannibalism and the other group never exposed to the cannibalism). We measured the head width at the level of eyes(HWE), the largest head width(LHW) and snout-vent length(SVL) of the each larva then calculated the ratio of the head size by dividing HWE by LHW. We found that exposure of indirect cannibalism in early life cycle cause the different polyphenism. Our result means the larval salamander responded to the chemical cue from conspecific.