• The Korean Journal of Malacology
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• v.11 no.2
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• pp.135-145
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• 1995

A morphological andk histochimical study on the amterior tintacular antenna of Korean sulg, Incilaria fruhstorferi was conducted under the light microscopic observations. The histological sturctures of the antenna were apparently divided into three parts such as the epithelium, the connective tissues and the muscular layers. The cells forming the antenna were classified into several types on the basis of their morphological and histochemical characteristics. The simple columnar epithelium cotering the whole antenna was composed of supporting cells, sensory neurons and type-a clear cells. The connective tissue was consisted of dispersed large cells, type-b clear cells and 7 types of secretory cills such as type-A, type-B, type-F, thpe-G, type-H, type-J and type-K. The large cells found in the form of group situated only in the stalk of the antenna. The large cells possessed relatively small nuclei as compared with their cytoplasm. The cytoplasm positively reacted upon alcian blue, and the nucleus was PASpositive. The type-a and type-b clear cells which were irregular in shape showed no evident reaction against various stains employed in the present study. The secrtory cells were observed mainly in the connective tissues and in the muscular layers. Histochemical components of the type-A, type-B and K were identified as acid mucopolysaccharides and those of type-F and H were neutral mucopolysaccharides. The muscular layders supporting the epithelium possessed the type-B and F secretory cells which were also observed in the connective tissues.

• The Korean Journal of Malacology
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• v.31 no.1
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• pp.43-48
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• 2015

Oxygen isotope ratios (${\delta}^{18}O$) of three Pacific oyster (Crassostrea gigas) specimens from the Neolithic Yeondae-do shell midden site, Tongyeong, Korea, were analyzed to determine the seasonality of shellfish gathering and site occupation. Oxygen isotope samples were taken from the left valve hinge sections of the specimens. Oxygen isotope values ranged between -0.1 ‰ and -2.4 ‰, between -0.2 ‰ and -2.9 ‰, and between 0.3 ‰ and -2.8 ‰ in oyster specimen #one, #two and #three, respectively. The isotope profiles showed seasonal temperature cycles, providing information related to the seasonality of shellfish gathering and site occupation. Hinge-edge oxygen isotope values of the specimens showed decreasing trends after passing through maximum values (winter), indicating that they formed during spring. Thus it can be assumed that during spring season, oysters were gathered and the site was occupied.

• The Korean Journal of Malacology
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• v.28 no.2
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• pp.109-116
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• 2012

In order to understand the effect of introduction of oyster rack culture on natural short-necked clam, Ruditapes philippinarum, stock, we investigated the status of natural clam stock prior to introduction of oyster rack culture at Yeongheung Coast of Wando Island. The growth equation of the clam was estimated as: $L_t=61.46{\cdot}(1-e^{-0.172(t+0.155)})$ from ring radius composition of shell. Instantaneous coefficient of total mortality and natural mortality were calculated as: 2.4087/year and 0.478/year, respectively. The age at first capture was estimated to be 2.55 year. The total biomass was estimated to 3.23 ton in the bed (0.8 ha). Applied by these parameters, the annual recruit biomass and the current yield per recruit (Y/R) was corresponded to $114.7individuals/m^2$ and $92.0g/m^2$, respectively. Maximum sustainable yield (MSY) was estimated 0.77 ton/year which was close to annual catches, 0.74 ton/year, in the area.

• The Korean Journal of Malacology
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• v.27 no.1
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• pp.29-33
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• 2011

This study was conducted to investigate the recruitment pattern of sessile organisms on the artificial substrates of PVC in Jangmok Bay, Geoje Island, southern coast of Korea. Five PVC plates were submerged from March to October, 2007 at one month interval, and two plates were retrieved after one month. The dominant recruiters were a green algae, Entermorpha prolifera in March, Mytilus galloprovincialis in April, M. galloprovincialis and Styela plicata in May, S. plicata and Bugula sp. in June. During August, Balanus amphtrite and anthozoans were dominant recruiters, and a serpulid worm, Hydroides ezoensis in October. There was a clear specific recruiting period of sessile faunas depending on their reproduction cycles in a sheltered embayment like Jangmok Bay.

• The Korean Journal of Malacology
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• v.23 no.1
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• pp.65-104
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• 2007

This catalogue is the result of a four-year survey of the mollusks of Jeju Island, the southernmost island in the Republic of Korea. Forty-eight survey stations were visited, with a total of 82 specific localities being sampled. Literature records were also obtained. Local and world distribution of each species is included. This survey reports a total of 1,072 mollusk species and subspecies; 1,015 marine and 57 land and freshwater. There are 812 gastropods, of which 755 are either entirely marine or have marine affinities. The best represented of the marine families are the Pyramidellidae, Trochidae, and Ovulidae. There are 225 bivalves, none being freshwater species, with the Veneridae, Mytilidae, and Arcidae having the largest number of species. Among the smaller classes there are sixteen Cephalopoda, eleven Polyplacophora, and eight Scaphopoda. Compared to mainland Korea, Jeju Island has a rather small terrestrial mollusk fauna and a depauperate freshwater one, with mainly Palearctic connections. The Helixarionidae and Bradybaenidae are the largest terrestrial families. The marine faunal affinities with the neighboring Japonic and Indo-West Pacific provinces are also discussed, revealing that this island's mollusk fauna is a blend of warm-temperate and subtropical-tropical species.

• The Korean Journal of Malacology
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• v.20 no.2
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• pp.107-110
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• 2004

The filtration rate and oxygen consumption of Anadara granosa bisenensis were measured at 4 different temperature (10$^{\circ}C$, 15$^{\circ}C$, 20$^{\circ}C$, and 25$^{\circ}C$) and 4 different salinity levels (20, 25, 35, and 40 psu), using an direct method under laboratory conditions. The samples were divided into two groups: a large-sized group (shell length: 34.58 ${\pm}$ 2.23 mm, body weight: 12.43 ${\pm}$ 0.44 g) and a small-sized group (shell length: 20.60 ${\pm}$ 0.85 mm, body weight: 4.41 ${\pm}$ 2.30 g). Filtration rate and oxygen consumption increased with the increase of various temperatures and salinity levels. Also, the filtration rate and oxygen consumption of the small-sized group were higher than those of the large-sized group. These results indicate that the filtration rate and oxygen consumption of Anadara granosa bisenensis depends on environmental conditions, especially on water temperature and salinity.

• The Korean Journal of Malacology
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• v.14 no.1
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• pp.9-17
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• 1998

동해 연안에서 채취된 뷔나스백합(Mercenaria stimpsoni)의 연령과 성장률을 이매패의 표면에서 확인된 연륜과 이매패 각질에서 분석된 산소동위원소비의 성장에 따른 변화를 이용하여 비교하였다. 뷔나스백합의 산소동위원소상은 일련의 주기적인 변화를 뚜렷하게 보여주며 이러한 변화진폭은 이매패가 성장한 해수의 온도변화에 일차적으로 제어된다. 산소동위원소상의 주기화 연륜의 관계로부터 뷔나스백합의 연륜이 해마다 여름철에 형성됨을 보여준다. 해수 온도의 계절적 변화와 산소동위원소비에서 얻어진 예측 온도와의 비교로부터, 뷔나스백합은 겨울철에 성장이 멈추는 것으로 사료된다. 또한 산소도위원소비는 뷔나스백합의 성장에 따른 전형적인 노화현상을 보여준다. 따라서 이매패가 성장하는 해수의 물리화학적 조건에 의해 제어되는 산소동위원소비는 뷔나스백합의 경우 연령과 성장률을 측정하는 독립적인 시간 척도가 될 수 있다.

• The Korean Journal of Malacology
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• v.14 no.1
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• pp.51-59
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• 1998

담수산 이매패류인 참재？, Corbicula leana를 대상으로 크기와 수온별로 카드뮴, 구리 및 수은 등의 중금속에 노출시켜 반수치사농도, 호흡률 및 여수율 등의 생리적 내성에 관하여 알아보았다. 17%C에서 작은 개체rnhr,-LC$^{50}$ 은 수은이 1.63 ppm이었으며, 카드뮴과 구리는 각각 7.45및 8.71 ppm으로서 수은에 비해 상당히 높은 값을 나타내었다. 큰 개체구의 경우는 수은이 2.62ppm이었으며, 카드뮴과 구리가 각각10.15와 10.20 ppm이었다. 22$^{\circ}C$의 경우 작은 개체구의 96 hr-LC$^{50}$ ppm은 카드뮴, 구리 및 수은이 각각 5.94, 7.08및 1.63 ppm이었으며, 큰 개체구에서는 각각 8.29, 8.35, 1.87ppm으로서 두수온구에서 모두 작은 개체구에서 중금속 오염원에 의한 영향이 컸으며, 독성순위는 수은>카드뮴>구리 순이었다. 한편 중금속 오염원에 노출시킨 참재첩의 수온-개체크기별 산소소비율과 여수율은 오염원의 농도증가에 따라 고수온에서 영향을 많이 받았으며, 특히 수은의 경우, 22%C-작은 개체구에서 호흡률이 50.7%, 여수율이 52.15%감소되고 있어 여수율이 보다 크게 영향을 받았다.

• The Korean Journal of Malacology
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• v.14 no.1
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• pp.33-40
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• 1998

A horizontal starch gel electrophoresis for enzyme proteins extracted from 2 species of Korean viviparid snails; Cipangopaludina chinensis malleata and C. japonica was carried out in order to elucidate their genetic relationships. A total of 10 enzymes were employed in three different kinds of buffer systems. Two loci from each enzyme of alcohol dehydrogenase, esterase, glucose phosphate isomerase, isocitrate dehydrogenase, iditol dehydrogenase, malate dehydrogenase and peptidase(VL); and only one locus dach from two enzymes, glycerlo-3-phosphate dehydrogenase and phosphoglucomutase were detected; but, four loci from peptidase(LGG) were observed. Most of loci in two viviparid species showed homozygous monomorphic banding patterns and some of them were specific as genetic markers between two different species. However, EST-1, MDH-1, PEP(VL)-1loci showed polymorphic banding patterns. Foru populations of C. chinensis malleata were more closely clustered in a dendrogram within the range of genetic identity values of 0.928-1.00, and these clusters were lineated with C. japonica at the value of 0.355. In summarizing the above results, two viviparid snail species dmployed in this study mostly showed monomorphic enzyme protein banding patterns, and genetic differences specific between two species.

• The Korean Journal of Malacology
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• v.10 no.1
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• pp.1-8
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• 1994

동양달팽이속(Nesiohelix)에 속하는 종으로 한국에서는 유일하게 서식하고 있는 종으로알려진 동양달팽이(Nesiohelix samarangae)성체의 눈에 대하여 해부학적 및 미세구조관찰을 실시한 결과 다음과 같은 결론을 얻을 수 있었다. 동양달팽이의 눈은 각막, 무세포성의 수정체, 망막및 신경망 등으로 구성되어 있는 바 가장 복잡한 구조를 보이는 부분은 망막으로서 이의상피는 2종의 원주세포로 구성되어있다. 그 하나는 광수용세포로서 세포의 상부세포질이 원추형 또는 피라미드형의 돌기를 이루었고 그 유리표면에는 긴 감간(microvilli)이 무수히 많이 존재하고 있으며, 돌기를 이룬 세포질 내에는 용해소체의 활성이 높게 나타난다. 또한 광수용세포들의 상부세포질에는 이웃해 있는 색소세포들의 세포질 돌기들이 여러개 침입해 들어와 있다. 그리고 핵 주변의 세포질에는 수많은 photic vesicle들이 군집을 이루어 존재한다. 다른 한 종류의 세포는 색소세포들로서 광수용세포들과는 달리 세포의 상부에 원추형의 세포질 돌기가 없고 다만 그 유리표면을 따라 광수용세포의 것보다는 굵고 짧은 많은 감간이 존재하는데 두 종류의 세포들에서 뻗어나온 감간들은 서로 만나 때로 파상을 이루고 있다. 망막 상피세포층의 기저막 아래에는 신경망이 컵모양의 망막을 따라 존재한다.