• Animal cells and systems
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• v.3 no.2
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• pp.127-131
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• 1999

The first zoeal stage of Pachycheles hertwigi Balss is described and illustrated. Its morphological characteristics are compared with those of other known species of Pachycheles. The first zoeas of P. hertwigi and P. stevensii are very similar, but they can be distinguished from each other by the length of carapace spine and the size of antennal exopod spinules.

• Animal Systematics, Evolution and Diversity
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• v.5 no.2
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• pp.89-105
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• 1989

농게(Ura arcuata) (달랑게과, 달랑게아과) 의 유생을 부화에서부터 첫 번째 게기까지 수온 $25^{\circ}C$ , 염분농도 33.3$\textperthousand$의 해수에서 사육하고, 각 유생기이 형태적인 특징을 기술 및 도식하였다. 이 종은 5기의 zoea와 1기의 megalopa 유생을 거쳐 첫 번째 게기로 변태하였다. 제 1 zoea 유생기는 제 1 소악의 내지에 4개의 말단강모와 제 2 악각의 기절과 내지에 각각 3개의 우상강모와 0, 0, 5 강모식을 가지고 촉각은 B형이었다. 이러한 특징들은 이미 보고된 같은 과의 유생들의 특징들과 잘 일치하고 있다.

• Animal Systematics, Evolution and Diversity
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• v.27 no.1
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• pp.53-58
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• 2011

The zoeal stages of Pisidia serratifrons are described and illustrated for the first time and its morphological characteristics are compared with those of three known Pisidia species of the family Porcellanidae. The zoea of P. serratifrons differs from those of other Pisidia (P. brasiliensis, P. dispar, and P. dehaanii), by having 11 spinules on the exopod of the antenna. In order to facilitate the study of plankton-collected material, a provisional key is provided for identification of the Korean porcellanid zoeae.

• The Korean Journal of Zoology
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• v.27 no.1
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• pp.56-67
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• 1984

털보 꼬마 풀게 Hemigrapsus sinensis Rathbun의 雌雄을 1983年 4月 10日 京畿道 蘇來방파제 바위틈에서 채집하여 飼育한 결과 동년 4月 22日 雌는 抱卵하여 동년 5月 6日에 孵化되었다. 털보 꼬마 풀게의 幼生을 孵化時부터 1期 Crab期까지 實驗室에서 溫度 $20\\sim24^\\circC$, 鹽分溫度 $31\\sim35%$에서 飼育하여 5期의 Zoea幼生과 Megalopa幼生을 얻어 形態學的으로 記述, 圖示하였다. 같은 亞科인 Varuninae의 게 幼生들과 比較 觀察하였다. 이 種의 特徵은 Zoea 1,2期의 第2觸角은 $B_3型$, Zoea 3,4,5期는 $B_2型$이고 尾節은 全 Zoea期를 通하여 B型으로 Zoea同定에 有用한 標準이 되리라고 본다.

• Journal of fish pathology
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• v.17 no.2
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• pp.139-144
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• 2004

In the present study, the effect of different water temperature (15, 20, 25, $30^\circ{C}$ and ambient) on survival, growth rate and intermolt period of zoeal and megalopal stage of tiger crab, Orithyia sinica were examined. The survival rate of zoeal and megalopal stages of experimental crab was observed high at $20^\circ{C}$ and ambient water temperature. The growth rate of crab larvae showed temperature-dependent increase. Therefore, the maximum growth rate was recorded at $30^\circ{C}$ temperature-regulated group in both zoeal and megalopal stage. However, temperature-dependent decrease in larval stages of crab during intermolt period has been observed in the present investigation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.9-18
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• 1968

A series of experiments since 1963 ha sbeen made on the artificial propagation of Penaeus oriental is for the purpose of improving breeding of the prawn. The results are as follows: 1. Spawning takes place in the evening, and almost completes before 10 o'clock p. m.. Number of spawns deposited by a prawn is 30,000 to 150,000. 2. Deposited spawns become nauplius stage after approximately 18 hours (about 13 hours in hatching tanks) at water temperature of $23\~25^{\circ}C$, and grow to first nauplius stage in subsequent 28 hours. 3. It takes about five days from first nauplius stage to zoea stage, and additional four or five days from first zoea stage to first mysis stage. 4. It takes approximately 2 to 3 weeks from spawning to post larva. 5. Hatching rate ranged from $1.4\%$ to $14.9\%$, with the average of $6\%$ in 1966 and $10\%$ to $35\%$ averaging $20\%$ in 1967.

• Animal Systematics, Evolution and Diversity
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• v.18 no.2
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• pp.191-201
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• 2002

The first zoeal stage of Heptacarpus rectirostris (Stimpson, 1860) is re-described and illustrated in detail from laboratory-hatched material. The first zoea of H. rectirostris is more closely related to that of H. futilirostris than to H. camtschaticus, H. pandaloides, and H. geniculatus by having the pterygostomial spine and two anteroventral denticles on the carapace. The former two species, however, can be readily distinguished by the presence (H. futilirostris) or absence (H. rectirostris) of the posterolateral spine on the abdominal somites 4-5. A provisional key to the first zoeas of Heptacarpus for which larval studies are known from Korea and adjacent waters is provided. A list of larval descriptions within the Hippolytidae from Korea and adjacent waters is also included.

• Animal Systematics, Evolution and Diversity
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• v.11 no.3
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• pp.389-408
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• 1995

The complete larval development of Hemigrapsus penicillatus(De Haan, 1835) from hatching to first crab stage was obtained by culture in the laboratory. Under culture conditions with salinity 33.3% , temperature $25^{\circ}C$, and photophase 14/10 h light/dark, the megalopa and the first crab instar were attained in minimum of 18 and 29 days after hatching respectively. Five zoeal stages and a megalopal stage are described and illustrated in detail. Morphological characters of H. penicillatus larvae were compared with those of other members within the subfamily Varuninae. Morphological differences among H. penicillatus, H. sanguineus and H. sinensis in megalopal stage are tabulated.

• Ocean and Polar Research
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• v.31 no.3
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• pp.257-264
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• 2009

Seventeen females of the mud crab Scylla serrata, from the State of Kosrae, Micronesia, were transported to the Fisheries Resources Research Institute, Gyeongsangnam-do, in oxygen-filled plastic bags. After acclimatization to a $30^{\circ}C$ holding temperature, nine females were selected for seed production trials. Spawning was hastened using eyestalk ablations; however, this may not be required in commercialscale mud crab seed production. Primary spawning produced an average of 2.4 million hatched larvae, whereas secondary spawning produced 0.4 million. About 10 days elapsed between spawning and hatching and 30 days between hatching and crablet. Mass mortalities up to 90% were observed between stages zoea 1 and zoea 2 in every trial. The highest survival rate from zoea 1 to crablet was estimated at 0.25%. Most commercial shrimp hatcheries in Korea are equipped with almost all necessary facilities and could be converted easily to mud crab hatcheries, able to run three to four times per year using hatchery technologies developed for blue crabs and Chinese mitten crabs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.716-722
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• 2012

The larval occurrence of the red snow crab Chionoecetes japonicus was investigated near Dokdo in the East Sea of Korea, and the larval timing of the genus Chionoecetes in world oceans was reviewed. C. japonicus larvae were collected seasonally at 12 stations in February, May, August, and November in 2011. A Bongo net with a 303 mesh was deployed with a double oblique tow. Larvae appeared from February to August, but no larvae were found in November. Zoea I occurred at nine stations with a few zoea II in February, and were found until August. The larval densities in February were high near the northern. In May, megalopa were found at eight stations with a few zoea II. No larvae were caught in November. The larval abundance in the research area peaked in February. Overall, the larval duration of the genus Chionoecetes in the world's oceans persisted for a long time, and Chionoecetes larvae occurred during the warm season in each area. The cold temperature at the sea bottom, where gravid females are found, may prolong larval production along the distribution range of the genus Chionoecetes.