• The Korean Journal of Malacology
• /
• v.9 no.1
• /
• pp.27-32
• /
• 1993

러시아의 극동 연안에서는 꼬막 아과 세 종이 출현하고 있다. 이들 중 Anadara inaequivalvis(Bruguiere, 1789)와 Anadara subcrenata(Lischke, 1869)는 신생대에 전멸된 개체군으로 알려져 있다. Anadara속의 형태학적 변이, 분류 및 지리적 분포에 대한 자료를 제시하였다.

• Development and Reproduction
• /
• v.16 no.3
• /
• pp.177-183
• /
• 2012

This study attempts to propose the possibility of the sex reversal in Tegillarca granosa and Ruditapes philippinarum by confirming the changes in the sex ratio with the shell length (SL) in the same population level. For analysis of sex ratio with SL, 1500 individuals of T. granosa (SL 10.1-45.0 mm) and 712 individuals of R. philippinarum (SL 15.1-70.0 mm) were used. Sex was analyzed histologically. The average sex ratios (F:M) of T. granosa and R. philippinarum were 1:1.22 and 1:0.96, respectively. However, sex ratio was found to differ when the clams were divided into groups according to SL in 5.0 mm intervals. Both species displayed the tendency of increase in the proportion of female with increase in SL. In this study, changes in the sex ratio in accordance with the growth of T. granosa and R. philippinarum are determined to be indirect evidence that signifies their sex reversal.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.38 no.2
• /
• pp.94-99
• /
• 2005

The gametogenesis of the surf clam, Tresus keenae, were investigated by SEM and TEM. Both the testis and the ovary had follicle tubes surrounded by inter-tubal tissue composed of adipogranular cells that provided storage function. In the vitellogenic oocyte, lipid droplets and lipid yolk granules were found in the vacuoles formed by the Golgi apparatus. Proteid yolk granules were formed by the endoplasmic reticulum and cortical granules in the cytoplasm during vitellogenesis. The mature sperm was primitive and resembled a jar with a cover. The sperm heads were approximately $2.00-2.30 {\cal}um$. The acrosomal rod projected in front of the acrosome. In addition, four large mitochondria were in the midpiece.

• The Korean Journal of Malacology
• /
• v.15 no.1
• /
• pp.63-69
• /
• 1999

Electrophoretic analysis was carried out to elucidate genetic relationships of four Korean scallops, Patinopecten yessoensis, chlamys ferreri ferreri, Chlamys swifti and Amusium japonicum japonicum, and of a Chinese population of C. ferreri ferreri purchased form a market. Glucose phosphate isomerase banding pattern was highly varied among eight loci. Three populations of C. ferreri ferreri were more closely clustered in a dendrogram within the range of Nei＇s genetic similarity values of 0.730-0.830. P. yessoenensis and Chlamys swifti were clustered with genetic similarity value of 0.647. These two clusters were lineated at the value of 0.598. A. japonicum japonicum was clustered with other three species at value of 0.541.

• Korean Journal of Environmental Biology
• /
• v.26 no.4
• /
• pp.279-291
• /
• 2008

The seasonal distribution pattern of the Bivalvia samples collected from 12 stations in Gamak Bay in April, July, September and November from 2001 to 2006. A total of 28 species (226.72$\pm$196.20 ind. m$^{-2}$) were identified. The COD has decreased from 3.30 mg L$^{-1}$ to 1.89 mg L$^{-1}$ level on average and especially, the COD of sediment has decreased from 21.51 mg g-dry$^{-1}$ to 16.99 mg g-dry$^{-1}$ level on average. Therefore, water quality level of Gamak Bay was improved from level 3 to 2. The dominant species over 1.0 percentages were composed of the total 13 species, and they occupied 96.75% of the total density of the Bivalvia. Major dominant species was Musculista senhousia 100.38 ind. m$^{-2}$ (22.16%), Moerella rutila 69.00 ind. m$^{-2}$ (15.23%), Theorafragilis 49.70 ind. m$^{-2}$ (10.97%), Mytilus edulis 42.18 ind. m$^{-2}$ (9.31 %), and Raphia undulata 40.99 ind. m$^{-2}$ (9.05%). This area could be divided into three groups by the cluster analysis based on the total species composition.

• The Korean Journal of Malacology
• /
• v.15 no.1
• /
• pp.21-30
• /
• 1999

This study was carried out to describe the growth of Ruditapes philippinarum on Chohwa and Toksan tidal flat in Kwangyang Bay, from June 1994 to July 1995. On the Chohwa tidal flat, the mean gran size, organic content and chlorophyll-a of the surface sediment were the range of 2.50-4.46 , 4.99-5.11%, 14.53-19.90 $\mu\textrm{g}$ cm$\^$-3/, and on the Toksan tidal flat, 0.83-1.66 , 2.22-2.34%, 6.20-6.90 $\mu\textrm{g}$ cm$\^$-3/, respectively. The shell length of R. philippinarum increased rapidly from spring to summer, and gently from summer to autumn, and ceased during winter. Fresh weight increased during spring and autumn, and decreased during summer and winter. condition factors also showed the same variations of weights. Synthesized annual growth pattern of 4 year classes in shell length fitted the von Bertalnffy growth model well. The annual growth of weight fitted the Gompertz model relatively well. The values of w, initial shell growth rate, and AGR$\sub$max/, maximum weight growth rate, on the Chohwa tidal flat were lower than those on the Toksan tidal flat. Comparing the growth patterns in the same tidal flat, growth rate was higher on the lover tidal flat than those on the higher tidal flat. In conclusion, the Chohwa tidal flat maintaining higher density showed lover growth rate, because of relatively insufficient food supply and inhabiting space.

• Korean Journal of Ecology and Environment
• /
• v.49 no.1
• /
• pp.22-30
• /
• 2016

Environmental changes exert harmful effects on organisms inhabiting coastal regions. These changes are also associated with reduced production in aquaculture farms. In this study, we investigated internal and external responses of two Bivalvia species (Crassostrea gigas and Mytilus galloprovincialis) in Gamak Bay under stressful environmental conditions in aquaculture farms. We investigated external responses such as weight, size, and environment exposure time, and analyzed the expression of the HSP70 gene. C. gigas HSP70 gene expression level was significantly high in the C3 aquaculture farm site, but the weight and size of C. gigas were high in the C2 aquaculture farm site. The response of C. gigas HSP70 mRNA was associated with the environmental exposure time in each aquaculture farm. Expression of M. galloprovincialis HSP70 gene was found to be significantly higher in the M2 aquaculture farm site than in the M1 site, whereas the weight of M. galloprovincialis was observed to be higher in the M1 site. The size and environmental exposure time of M. galloprovincialis were similar between M1 and M2 sites. In addition, HSP70 sequences of C. gigas and M. galloprovincialis showed high similarity with that of another marine species. According to our results, there were differences in internal responses following environmental stress in aquaculture farms, with respect to HSP70 gene expression. The results suggest that the HSP70 gene is a useful molecular indicator for monitoring stress responses in Bivalvia species in the field.

• The Korean Journal of Malacology
• /
• v.30 no.2
• /
• pp.135-138
• /
• 2014

We report two new records Korean marine bivalves. The new record species are Siliqua albida (Adams & Reeve, 1850) and Macoma (Macoma) middendorffi Dall, 1884. As a result, the family Pharidae in Korea turned out to be 8 species of 4 genera and Tellinidae are 37 species of 15 genera.

• The Korean Journal of Malacology
• /
• v.13 no.2
• /
• pp.193-201
• /
• 1997

1990년 3월부터 1991년 2월까지 전라북도 군산 연안에 서식하는 동죽을 채집하여, 순간성장율, 순간사망율, 평균 생체량, 연간 생물생산력에 대하여 조사하였다. 치패는 각장 약 0.75 mm가 7월에 처음 채집되었으며, 0-5세의 6개 cohort로 구분되었다. 순간성장률은 여름철에 ？고 겨울철에 낮았지만, 순간사망률은 여름철에 높았다. 조사지역에서 동쪽 개체군의 연간평균 생체량은 3.865 g/$m^2$이었으며, 연간생산량은 3.933 g/$m^2$이었고, 연간 회전율은 1.020, 회전시간은 0.986년으로 추정되었다.

• The Korean Journal of Malacology
• /
• v.24 no.2
• /
• pp.89-92
• /
• 2008

A new species of the mytiloidean freshwater bivalve is described from Baengnyong Cave, Pyeongchang-gun, Gangweon-do. Limnoperna coreana n. sp. belongs to the genus Limnoperna Rochebrune, 1882 with the byssus. This species has a small shell with the glossy surface and rounded-triangular and differs morphologically from all of its congeners.