• Biomedical Science Letters
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• v.26 no.3
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• pp.217-225
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• 2020

Scuttle fly which moves abruptly after standing for a while and stop suddenly to rush off again, is a fly species in the Phoridae family. This species like rotten organic materials and it is known to proliferate even in the industrial materials including organic solvents. These characteristic behaviors of the scuttle fly seem to be related to muscular and nervous system or neurotransmitters. Thus, we focused at the neurotransmitter, corazonin (Crz) that is known to be related to resistance to stress and investigated the developmental process of the neurons in the scuttle fly. Corazonin is a neuropeptide being expressed in the central nervous system (CNS) and is known to control mainly physiological functions and behaviors. Its many functions that have been proposed are still in controversy. In this studies, we found that there are three groups of corazoninergic neurons in the larval CNS of the scuttle fly and these neurons undergo distinguishable changes through metamorphic process compared to different fly species. Larva has 3 pairs of Crz neurons at the dorsolateral area of the brain, 1 pair at the dorsomedial brain and 8 pairs at the ventral nerve cord.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.677-683
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• 2011

Eleven individual larvae (3.6-8.0 mm notochord length, NL) were collected from the southern East Sea of Korea in July, 2010, and the adjacent Sea of Jeju Island in August, 2011. Five individuals were identified using mitochondrial DNA cytochrome oxidase subunit I (COI) sequences (494 base pairs). All were identified as Auxis rochei, their mtCOI sequences being consistent with those of adult A. rochei (d=0.000), followed by Auxis thazard (d=0.027). In terms of morphology, A. rochei larvae showed a preflexion stage of 4.8 mm NL, but a flexion stage between 5.2-6.2 mm NL, and subsequently a postflexion stage between 6.6-8.0 mm NL. During the larval stage, A. rochei differed from A. thazard in having no (or few) melanophores in the lateral caudal region.

• Korean journal of applied entomology
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• v.20 no.2 s.47
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• pp.98-102
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• 1981

For the investigation of seasonal fluctuation of immature (lavae and pupae) beanfly, infestation rates, and habit, several soybean-cultivars were planted at Kumgok Experiment Farm of KAERI by three different planting times at 25-day intervals. Infestation rates of beanflies were ranged from $85\%\;to\;100\%$ in accordance. with the planting dates, where an increase in infestation rate was found with delay in planting dates. Immature beanflies were already observed from lune 20 by plant dissection counts. Three peaks of the seasonal fluctuation of lava were shown by occurring on July 10, August 10 and 50 during the soybean cultivation, while two peaks of pupal appearances were found. The most high peaks of lavae and pupae occurred on August 10 and 30, respectively. The lava were habitable in the pith or cortex tissue of soybean stem. They prepared tiny hole on the axilla as well as the internode of stem, and then they pupated in the holes from which the adults are able to escape. Immature beanfly seemed to prefer invading to the underground part of the stem when the soybean plants were in young stage.

• Korean Journal of Ichthyology
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• v.4 no.2
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• pp.31-43
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• 1992

The blenniid fish, Entomacrodus stellifer light(Herre) is distributed in the coastal waters of southern Japan and south-eastern Korea. Matured adults of blenniid fish were collected from the rocky shore of Namchun-dong, Nam-gu, Pusan, Korea in July, 1991. The observations were made on the morphology and skeletal development of the reared larvae and juveniles. The lavae reached 5.80mm in mean total length(MTL) in 10 days after hatching. A this time the larvae have absorbed the yolk completely and became postlarvae. Melanophores are distributed on the fin membrane of the lower part of pectoral fin and ventral margins of tail. The larvae averaged 6.20mm in TL and the caudal notochord flex at $45^{\circ}$ in 13 days after hatching. The part of the fin-fold of the future dorsal and anal fins became high. The lavae reached juvenile stage in 31 days after hatching and attained 15.80mm in MTL, and all fin-rays was formed. Ossification of the cranium took place at 6.20mm of MTL(11 days after hatching) in parasphenoid. Vertebrae began to develop from the anterior end to ossify posteriorly. Ossification of all bones nearly completed when the larvae reached to 15.80mm in MTL (31 days after hatching).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.6 no.3_4
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• pp.112-122
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• 1973

Philometroides carassii (ISHII, 1931) is a parasitic nematode of Carassius auratus and gold fish. Recently a large number of parasitized fishes by this nematode have been reported by fish farmers in Korea. The present investigation was aimed to find out the life cycles of the parasites and effects of chemotherapeutic medicines on the emerged larvae from the adult parasites. Results of the study are summarized as follows : 1. Intermediate host of p. cararsii is a freshwater copepod, Cyclops sp. and the invaded lavae in the body cavity of copepod are capable for parasitizing the fish host after 3 hours of invasion. 2. The lavae eaten directly by the fish host are digested or excreted. 3. The larvae invaded in the fish intestine through the intermediate host pass into the body cavity in 1 to 10 days, and become subadult stage. After 18 to 20 months the subadults parasitic in the body cavity of the Carassius auratus, penetrate through muscle fissile into tile caudal fin where they become adults. Whereas those parasitic in the body cavity of the gold fish, 7 to 8 months the sutadults penetrate through muscle tissue into the caudal fin where they become adults. 1. Male subadults found in the body cavity of the Carassius auratus and gold fish, were larger than females, This is the first record of male subadults occurring in the fish host. 5. Among four different :drugs tested, most of all larvae died in 4 ppm of dipterex in 5 days. But no adults were harmed even in 6 ppm dipterex in 11 days.

• Journal of Life Science
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• v.12 no.4
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• pp.407-415
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• 2002

The survival of the early larvae of the freshwater crab, E. japonicus, fed on different diets at 22土1$^{\circ}C$ and 24$\pm$1% were studied in the laboratory. The larvae in the control (no feed) lived for 4 days (1~2 zoeal stages), and in the experimental container of non-living foods (egg Powder, soy bean Powder, Pellet Powder, millet Powder, and mussel meat), they were lived for 7~9 days (2~3 zoeal stages), When the larvae fed on phytoplankton (Chlorella ellipsoid., Skeletonema costatum. and Chaetoceros gracilis), they lived for 10, 18, and 19 days(3~5 zoeal stages), and fed on zooplankton (Artemianauplii and rotifer), they were reached to the juvenile stage in 24 and 25 days, respectivily. When the larvae fed on a mixed diets (see table 1). it was more effective than a single food diet, and the most effective diets included Chaetoceros gracilis, Artemia nauplii and rotifera, in which the larvae reached the juvenile stage in 22 days, and the survival was 73%.

• Korean Journal of Ichthyology
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• v.4 no.1
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• pp.1-13
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• 1992

The gobiid fish, Luciogobius guttalus Gill has an anguilliform with some blackish and reddish brown color in life. It grows up to 90mm in total length. The specimens have been collected from several localities in the southern parts of Korea and Hokkaido, Japan. During the ebb tide, the fish was found in high level of intertidal zone exposed to the air among pebbles in the hollows and slopes of rocks. There are also some other small gobiid fishes comprising 3 species of relative gobies and 1 species of blennioid fish. A total of 5 egg masses were collected from the coast of Haeundae in April to May 1990. Each egg mass was deposited in one layer on the underside of a stone embedded in pebbles and guarded by the male parent. The eggs are club-shaped ranging from 2.71 to 2.80mm in long axis and from 0.65 to 0.74mm in short axis. The eggs were hatched in 98 hours after incubatied at the temperature varying from 19.5 to $25.5^{\circ}C$The newly hatched larvae were from 3.85 to 4.00mm in total length with 35~36 myomeres. In eleven days after hatching, total length reached 5.50mm. The part of the fin-fold of the future dorsal and anal fins became high. In sixteen days after hatching, the lavae averaged 6.20mm in total length and the caudal notochord flex at $45^{\circ}$. The larvae reached the juvenile stage in 48~50 days after hatching and attained 12.80~14.00mm in total length, and all fin-rays was formed. Ossification of the cranium took place at 5.50mm of mean total length in parasphenoid and basioccipital. Ossification of the visceral skeleton occurred in areas where active movements of bones are required, notalbly in the parts of feeding and respiration. Vertebrae began to develop from the anterior end to ossify posteriorly. Neural and haemal spines of vertebrae ossified always prior to the corresponding centra. When larvae reached to about 6.60mm in mean total length (17~18 days after hatching), jaw bones were more repidly ossified than vertebrae and cranium. Ossification of all bones nearly completed when the larvae reached to 13.40mm in mean total length (47~50 days after hatching).