• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.1
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• pp.38-42
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• 2001

Molt-staging of Metapenaeopsis dalei was determined by microscopic observation on their setal development of dissected uropods, Five major stages (Stage A, B, C, D and E) were defined by the morphology of setal development. Premolt stage (Stage D) can be divided into 4 distinctive substages ($D_1{\sim}D_4$) according to the premolting processes. The setal cones were formed at Stage B under the old cuticle, and the setal shafts were visible at the end of such Stage $D_1'$. The casting process of the old cuticle lasted less than 1 min. The molt stages in M. dalei thus are generally similar to those of other shrimp species.

• Animal Systematics, Evolution and Diversity
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• v.23 no.1
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• pp.9-20
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• 2007

The complete larval development of Chiromantes haematocheir was obtained by laboratory rearing. Five zoeal and one megalopal stages are described and illustrated in detail. Morphological characteristics of the larvae slightly differ from those of Lee (1988), especially in the setal presence of mouthpart appendages. Seven sesarminid zoeas (Parasesarma acis, Parasesarma pictum, Perisesarma bidens, Sesarmops intermedius, Chiromantes dehaani, Chiromantes haematocheir, and Nanosesarma gordoni) can be distinguished from each other in characters of the carapace spines, the antennal exopod and the fork of telson. A provisional key is first provided to aid the identification of seven sesarminid zoeas in Korea.

• Animal cells and systems
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• v.10 no.1
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• pp.7-14
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• 2006

Novactaea pulchella was reared in the laboratory, from hatching to the megalopal stage at $25^{\circ}C$. The larval stage of it consists of two zoeal and one megalopal stages. The first zoea of the present study differs from that described by Terada (1990) in the setal presence of the carapace, the maxilla and the maxilliped, and the lateral process on the abdominal somite. It is reported for the first time that brachyuran zoeas belonging to a species share two types of lateral processes on the abdominal somites. They are either on the abdominal somites 2 and 3 or on abdominal somites 2 to 5. A provisional key is provided to aid the identification of the actaeine zoeas in Korea and the adjacent waters.

• Animal cells and systems
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• v.14 no.2
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• pp.129-136
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• 2010

The introduced spider crab Pyromaia tuberculata was collected from Korea in 2005 and it was ovigerous. After hatching, larvae were reared in the laboratory at $20^{\circ}C$. The larval stage of the species consists of two zoeal and one megalopal stages. The larvae of the Korean species differ somewhat from those from New Zealand described by Webber and Wear (1981; N Z J Mar Freshwat Res. 15:331-383) and from Brazil described by Fransozo and Negreiros-Fransozo (1997; Crustaceana. 70:304-323.) in the setal presence of the antennule, the maxillule, the maxilla and the maxillipeds, and the abdomen. It is found that Fransozo and Negreiros-Fransozo have overlooked some setae on the basis of the zoeal maxillipeds and that re-examination of their larvae is needed. Also, it is found that the Inachoididae is heterogeneous based on the zoeal morphology because two distinct groups exist in the family.

• Animal cells and systems
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• v.11 no.1
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• pp.69-77
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• 2007

Both sexes of a new species of Miraciidae belonging to the genus Amonardia Lang, 1948 are described. All materials collected from the cultivated brown alga, Undaria pinnatifida of Gijang, Korea. So far only one species, A. normani (Brady, 1872) from the algal bed at Jindo Island was recorded in Korea. The new species can easily be distinguished from its congeners by the combination of characters as follows: (1) shape of first antennular segment in female, (2) setal formular of mandible and maxillule, (3) setae of female sixth leg in female, and (4) shape of P2 endopod and exopod of fifth leg in male.

• Journal of fish pathology
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• v.7 no.2
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• pp.83-94
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• 1994

Bonnierilla namhaesius n, sp, is described based on the specimens recovered from the ascidians, Halocynthia roretzi Von Drasche in Namhae Islands, Korea, This is distinguished from congeners by having a combination of characters : setal formula 3, 17+1 hook, 9+1 aesthete, 5, 3, 2, 2+1 aesthete, 7+1 aesthete respectively on eight segments of antennule, II, 5 on distal segment of the second leg to fourth leg exopod, and 2, 3, I on distal margin of caudal ramus. This is the second record of the male, and first record of the copepodid in the genus Bonnierilla.

• Ocean and Polar Research
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• v.32 no.4
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• pp.369-377
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• 2010

To characterize ecotoxicological responses to a natural estrogen, $17{\beta}$-estradiol, we evaluated the life-history of the parental ($F_0$) and first generation ($F_1$) of the harpacticoid copepod, Tigriopus japonicus sensu lato. We evaluated the survival of nauplii and copepodites, the number of days until the emergence of copepodites and adult males, the sex ratio, brooding success, and the first brooding day of adult females. No significant differences in the survival rate were noted in response to treatments with different concentrations of $17{\beta}$-estradiol. However, $17{\beta}$-estradiol induced developmental delay and skewed the sex ratio toward males. Copepod development was delayed significantly in the 0.1 and $1\;{\mu}g\;l^{-1}$ $17{\beta}$-estradiol treatment groups relative to the control group, with a more pronounced delay in the $F_1$ group. Body length and biomass were significantly smaller in the $17{\beta}$-estradiol treated groups than in the controls. The male emergence of T. japonicus s.l. was very high in the 10 and $30\;{\mu}g\;l^{-1}$ $17{\beta}$-estradiol treatment group. Furthermore, exposure to $17{\beta}$-estradiol resulted in morphological deformities such as shrinking and swelling of the urosome, twisted setae of the caudal rami, setal loss of swimming legs, abnormal segmentation of antennules, and dwarfism.

• Korean Journal of Veterinary Research
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• v.24 no.2
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• pp.213-226
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• 1984

Scanning electron microscope (Model; SEM ISI-DS-130) was used to observe the fine surface structures of the predominant cattle tick Haemaphysalis longicornis Neumann 1901 (Acarina: Ixodidae) in Korea and some SEM microphotographs were presented in this pictorial monograph. Brief descriptions of the main contents are consisted of followings; L Mean body size is 2.43mm in unfed males and 2. 58mm in unfed females, the eyes are absent. 2. The scutums are inornated but there are some short-setae on the surface of the body. 3. The festoons on the dorso-marginal part of the body are present and segmented with 11 sectors. 4. The cornua is well-developed and the bypostome dentition is usually 5/5 in both sexes but rarely 4/4 also seen. 5. There is no dorsal projection on the anteriointernal margin of the palpal article 2, howevever, there are well developed dorso-internal setae with setal fossa on it. 6. The joints of the legs (Coxatrochanter and trochanter coxa, etc) are well developed.

• Fisheries and Aquatic Sciences
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• v.26 no.11
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• pp.649-659
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• 2023

The present study compared the structure of mixilliped of Fenneropenaeus chinensis between the larval and adult stage and investigated the effect of the structural difference on the immunity of F. chinensis. A fourteen day and a one-month long culture trial were conducted each with postlarvae and adults of F. chinensis in the biofloc, mixed water (50% biofloc:50% clear seawater) and seawater control. Immune-related genes mRNA expressions of postlarvae was analysed by quantitative reverse transcription polymerase chain reaction (qRT-PCR). And the analysis of adult stage immunity was carried out using phenoloxidase (PO) enzyme activation in haemocyte. In the postlarvae, the final body weights were 51.43 and 58.47 mg for the biofloc water and the control seawater, respectively. On the other hand, the final body weights of the adults were significantly different between biofloc water and seawater. The survival rate showed the opposite trend to the growth rate. Immune related genes mRNA expression levels in the postlarvae in the biofloc water were significantly lower than those in the seawater. While, the adult stage showed significantly higher PO enzyme activations in the biofloc water than in the seawater with the PO enzyme activation increasing proportionally to the biofloc concentration. This result is considerably explained by the observations of setal morphological structures of the third maxilliped: postlarvae have short serrulated setae that compose the small 'net' structure while adults had long and dense plumose setae. It is understood that the morphological difference of the maxilliped structure resulted in the different feeding abilities in the postlarvae and the adult F. chinensis to use bioflocs as food source.