• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.1005-1012
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• 1997

Fine structural changes of the germ cells during spermatogenesis in the goldeye rockfish, Sebastes thompson; were examined by means of the transmission and scanning electron microscopy. A spermatogonium has a large nucleus with a single nucleolus in the interphase. Primary spermatocytes are characterized by the formation of chromatin clumps and presence of the synaptonemal complex in the nucleus. The nucleoplasm of secondary spermatocytes is more condensed than that of primary spermatocytes, and the cytoplasm contains numerous mitochondria, endoplasmic reticulum and Golgi complex. The nuclei of spermatids in metamorphosis show sickle-like shape as the nucleoplasm becomes more condensed. In the cytoplasm of spermatids, the proacrosomal granules are not found at all. A spermatozoon consists of head, neck and tail. The acrosome is absent in the head. Four to five cytoplasmic collars are observed in the posterior portion of the head of spermatozoon. The well developed axonemal lateral fins are observed in the flagellum of spermatozoon.

• Korean Journal of Veterinary Research
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• v.14 no.2
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• pp.221-225
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• 1974

1. The length of Trypanossoma was $20{\sim}40{\mu}m$ (including flagellum) in dairy cattle in Korea, 2. Crithidia of Trypanosoma was found out in the head of depressed Tabanid fly and 77% in the flies. 3. The Trypanosoma in the tryptose blood agar was changed its form from 6 weeks after cultivation. 4. Infectious rate of Trypanosoma in dairy cattle was the same as in Korean cattle. 5. Infectious rate of Trypanosoma in dairy cattle was higher in summer than in winter. 6. No Trypanosoma was found in the blood from the jugular vein of calves born in winter. 7. Erythrocyte increased while leukocyte decreased in nummber in the blood of the cattle infected with Trypanosoma.

• The Korean Journal of Malacology
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• v.10 no.1
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• pp.9-18
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• 1994

This study was conducted to compare the genital organs of 14 land snail species belonging to family Bradybaenidae in Korea. The species used for present experiment were characterized by well developed dart sac, accessory sacs and two mucous glands between accessory sacs. No flagellum in the snails of three species employed(Acusta despecta sieboldiana, Koreanohadra kurodana, K. koreana) was observed in this study. The similarity value between Koreanohadra kurodana and Koreanohadra koreana (S=0.834) was more higher than the other species pairs. The higher value followed was recorded between Aegista gottschei and Aegista pyramidata (S=0.761). The clustering type by anatomical genital organs was similar to that analysed by the shell morphologies.

• Applied Microscopy
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• v.28 no.2
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• pp.181-191
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• 1998

The spermatogenesis of pale chub (Zacco platypus) was investigated morphologically. The testis of pale chub contained numerous testicular sacs. These testicular sacs were bounded on neighboring sacs by single layer of squamous cells. Also, differentiated sperms were filled in the sacs. In the stage of spermatogonium, the germ cells had a large nucleus and a distinct nucleolus, and mitochondrial development was prominent. In the primary and secondary spermatogonia, these cells had a round electron-dense nucleus, reduced cytoplasm, and mitochondria were congregated in the side of cytoplasm. The highly condensed chromatin of sperms was electron-dense, the acrosome was not found in the head of the sperm and a motile flagellum consisted of an axoneme with a typical 9+2 pattern of microtubules.

• Animal Systematics, Evolution and Diversity
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• v.20 no.1
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• pp.1-8
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• 2004

The first zoea of R. uritai is described in detail, based on laboratory-hatched material. The first zoea of R. uritai can be distinguished from that of R. conspiciocellus and R. durbanensis by the rostrum downwards, overreaching distal margin of the outer flagellum of the antenna, the endopod of the antenna with short seta as well as long plumose seta distally, and the scale of the antenna six-segmented. The shape of the telson can be a distinguishing character of the first zoea of Rhynchocinetes from that of Cinetorhynchus.

• Animal Systematics, Evolution and Diversity
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• v.12 no.4
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• pp.281-287
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• 1996

A new species of Caprellidae, Ca;rella multitberculum collected from 3 localities in the coast of the East Sea in Korea, is described and illustrated. This new species is very close to Caprella soyo Arimoto, 1934 from Japan, but is distinguished from it by having the more numerous small tubercles on body surface, the shorter flagellum of antenna 1 and the smaller appendages of abdomen. Moreover, the shape of propodus of gnathopod 2 reveals several prominent differences between the two.

• Animal Systematics, Evolution and Diversity
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• v.35 no.4
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• pp.168-181
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• 2019

Two cirolanid isopods, Eurydice longiantennata Nunomura and Ikehara, 1985 and Metacirolana japonica (Hansen, 1890), are newly reported based on the materials collected from the subtidal zone around Jeju Island. Eurydice longiantennata can be distinguishable from its congeners by the following features: body length is 5 mm; antennule is not extending beyond the cephalon; flagellum of the antenna is consisted of 31 flagellar articles; and pleotelson has eleven teeth and twelve setae distally. Metacirolana japonica is distinguished from its related species by the following characteristics: body is not ornament; pleonite 1 is entirely visible dorsally in male; pleotelson is gradually tapering distally; and uropodal rami have serrate margins.

• Journal of Species Research
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• v.12 no.2
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• pp.150-153
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• 2023

A fern spore-feeding stathmopodid species, Calicotis latebrifica Terada, 2016 is reported for the first time from Korea on the basis of one male and three females from Island Chujado, Jeju Province. This record represents the third example of the Korean Lepidoptera associated with fern spores for larval food items. The species is similar to Cuprina fuscella Sinev, 1988 in feeding on fern spores but differs from the latter in the body color and the presence of cilia on the ventral side of antennal flagellum. The genus Calicotis is introduced for the first time to the Korean fauna. Calicotis latebrifica has been known exclusively from Japan before this study. Larval habits for feeding and shelter construction were demonstrated from field observation and rearing in captivity. A new host plant of C. latebrifica, Dryopteris nipponensis Koidz. is recorded. The habitus and genitalia of both sexes are briefly described for C. latebrifica with photographs.

• The Korean Journal of Zoology
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• v.20 no.1
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• pp.29-40
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• 1977

The authors examined fresh-water gammarid materials which were collected from streams in 20 localities of South Korea during the period from 1965 to 1977. As the results of the observation, the authors have concluded as follows: 1. These fresh-water gammarids belong to Gammarus pulex-group and are distributed widely in mountain-streams of mainland and surrounding islands of South Korea. 2. The present specimens are different from the subspecies, G. pulex koreanus Ueno, 1940 which was described originally from North Korea. In the latter, the pulmose setae of third uropod are limited only to the outer margin of both rami. The peduncle and flagellum of second antenna are fringed with a few short setae and the flagellum is provided with calceoli. In the former, both margins of inner ramus and outer margin of outer ramus of third uropod are fringed with long pulmose setae. The peduncle and flagellum of second antenna have abundant relatively long setase and the flagellum is not provided with calceoli. 3. The present specimens are different from the subspecies, G. pulex sobaegensis Ueno, 1966 which was described originally from South Korea. The latter dwells in cave, while the former dwells in mountain-stream. In the former, the arrangements of pulmose setae of third uropod and the setation of second antenna are similar to those of the latter. But they are quite different from each other in several characters such as shape of upper lip, shape of fifth article of second gnathopod and numbers of incisions on front distal margins of coxal plates 1-3. The former has spines on surface of coxal plates 1-3, but the latter has not. In females, the former has four pairs of marsupial plates, while the latter has three pairs. 4. The present materials show local variations. Therefore, they could be divided into 3 local groups. The first group (specimens from Mt. Odae and Mt. Sogeumgang) has pulmose setae on the both margins of both rami of third uropod and second article of outer ramus is relatively long. In general, this group has setae sparsely on the both rami and especially a few setae on the outer margin of outer ramus. The second group, which are widely distributed in South Korea, has pulmose setae on the both margins of inner ramus and on the outer margin of outer ramus of third uropod. In the third group (specimens from Mt. Soyo), the pulmose setation of third uropod is similar to that of the first group, but the second article of outer ramus is very small.

• Korean Journal of Ichthyology
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• v.18 no.4
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• pp.311-318
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• 2006

Ultrastructure of germ cells, the cyst epithelial cells and interstitial cells during spermatogenesis of the stone flounder, Kareius bicoloratus (Pleuronectidae) sampled on the west coast of Korea were investigated by electron microscopic observations. In the primary spermatocyte, the synaptonemal complexes appear in the zygotene stage of the prophase during maturation division. In the growing testis, especially, the interstitial cells (Leydig cells) appear near the primary, secondary spermatocytes and spermatids. Well-developed interstitial cells (steroid hormone secreting cells) which are located in the interlobular space in growing testis have three morphological characteristics of a vesicular nucleus, mitochondria with tubular cristae and smooth endoplasmic reticulum. During spermatogenesis, the primary and secondary spermatocytes attach to the cyst epithelial cell (Sertoli cell) having an elongated ovoid or triangular nucleus and several mitochondria in the cytoplasm. In the growing testis, lipid droplets, the mitochondrial rosettes and glycogen particles appear in the cytoplasm of the cyst epithelial cells near the secondary spermatocytes and spermatids. Particularly, the mitochondria, endoplasmic reticulum, little lipid droplets and the large amount of glycogen particles are present in the cytoplasm of the cyst epithelial cell in the late growing testis. In the late stage of spermiogenesis, the proximal centriole is joined to the nuclear envelope, the distal centriole forms the basal body of the flagellum and gives rise to the axial filament of the flagellum. No acrosome of the sperm is formed as seen in other teleost fish. The head of the spermatozoon is approximately $3{\mu}m$ in length and its tail is about $30{\mu}m$ in length. The axoneme of the tail flagellum of the spermatozoon consists of nine outer doublet microtubules at the periphery and two centrial singlet microtubules at the center. The spermatozoon of this species has two axonemal lateral fins. Especially, the cyst epithelial cells which located near groups of gametes in the various stages, show three functions: nutrition, phagocytosis and steroidogenesis. Especially, the nuclei of cyst epithelial cells in the recovery stage of the testicular developmental stages appear to be irregular in shape after spermiation. Of three functions of the cyst epithelial cell, several characteristics of phagocytosis are showed in the cytoplasm of the cyst epithelial cells in the recovery stage of the testicular developmental stages. At this stage, therefore, it is assumed that the cyst epithelial cells are involved in degeneration and resorption of undischarged germ cells after spermiation.