Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
The Korean Journal of Malacology
Journal Basic Information
Journal DOI :
The Malacological Society of Korea
Editor in Chief :
Volume & Issues
Volume 21, Issue 2 - Dec 2005
Volume 21, Issue 1 - Jun 2005
Selecting the target year
Sexual Maturation and Artificial Spawning of the Hard Clam, Meretrix Iusoria (Bivalvia: Veneridae) on the West Coast of Korea
Chung, Ee-Yung ; Kim, Yong-Min ; Hur, Young-Baek ; Ryu, Dong-Ki ;
The Korean Journal of Malacology, volume 21, issue 2, 2005, Pages 81~93
Reproductive cycle with the gonadal phases, first sexual maturity, artificial spawning amount by the size and spawning interval of the hard clam, Meretrix lusoria were investigated by histological observations and morphometric data by artificial spawning induction. Meretrix lusoria is dioecious and oviparous. The reproductive cycle of this species can be classified into five successive stages: early active stage (January to March), late active stage (February to May), ripe stage (April to August), partially spawned stage (June to September), and spent/inactive stage (September to February). The spawning period was from June to September, and the main spawning occurred between July and August when the seawater temperature exceeds over
. Percentage of first sexual maturity of female and male clams ranging from 40.0 to 45.0 mm in shell length was over 50%, and all clams over 50.0 mm in shell length sexually matured. Female and male clams ranging from 40.0 to 45.0 mm in shell length are considered to be two years old. Therefore, we assume that the hard clams of both sexes begin reproduction from two years of age. The mean number of the spawned eggs increased with the increase of size (shell length) classes. In case of artificial spawning induction, the number of spawned eggs from the clams of a sized class was gradually decreased with the increase of the number of the spawning frequencies (the first, second, and third spawnings). In the experiments of artificial spawning induction during the spawning season, the interval of each spawning was estimated to be 15-18 days (average 17 days).
Ultrastructural Study on Spermatogenesis and Sexual Maturation of the Male Jicon Scallop, Chlamys farreri on the West Coast of Korea
Chung, Ee-Yung ; Park, Ki-Yeol ; Song, Pal-Won ;
The Korean Journal of Malacology, volume 21, issue 2, 2005, Pages 95~105
Gonadosomatic index, reproductive cycle, spermatogenesis and first sexual maturity of Chlamys farreri were investigated by cytological and histological observations, from January 1998 to December 1999. The gonadosomatic index (GSI) rapidly increased in April and reached a maximum in May when seawater temperature rapidly increase. Then the GSI gradually decreased from June to August when spawning occur. Accordingly, monthly changes in the GSI in males coincide with the reproductive cycle. The spermatozoon of Chlamys farreri is the primitive type found in external fertilization species. The head of the spermatozoon is approximately
in length including the acrosome measuring about
in length, and its tail was approximately
, the axoneme of the tail flagellum consists of nine pairs of microtubules at the periphery and a pair at the center. Five spherical mitochondria around the centriole (the satellite body) appear in the middle piece of the sperm. The spawning period was from June to August and the main spawning occurs from July to August when seawater temperatures are greater than
The reproductive cycle of this species can be categorized into five successive stages; early active stage (January to March), late active stage (March to April), ripe stage (April to August), partially spawned stage (June to August), and spent/inactive stage (August to January). Over 50% of male scallops attained first sexual maturity between 50.0 and 60.0 mm in shell height, and 100% of those over 60.0 mm in shell height achieved maturity. Accordingly, we assume that male individuals begin reproduction at three years of age.
Influence of Water Temperature on Spawning Induction, Larval and Spat Rearing of Trumpet Shell, Charonia lampas sauliae
Seon, Seung-Cheon ; Kim, Jae-Min ; Jung, Choon-Goo ; Yun, Seong-Jong ; Kang, Kyoung-Ho ;
The Korean Journal of Malacology, volume 21, issue 2, 2005, Pages 107~111
In the present study, the fecundation and fertilization behaviors of the trumpet shell, Charonia fampas sauliae were observed from November 2003 to March 2004. Female has multiple fecundation and multiple fertilization, and the fertilization continued for two days. The fertilized female stayed with the egg mass to protect the eggs, and the fecundation was made during the fertilization. The highest survival rate of egg capsule was 60% at
. Charonia lampas sauliae fed with Chaetoceros calcitrans, Isochysis galbana, and Pavlova lutheri. Growth and survival rates of C. lampas sauliae in the conditions of various water temperature were observed. The highest survival rate was 23% at
reared for 60 days. The growth was presented in the
group, with shell length from
during the experiment.
Study on the Natural Spat Collection of the Pen Shell, Atrina pectinata
Son, Pal-Won ; Ha, Dong-Soo ; Lee, Chang-Hun ; Jang, Dae-Soo ; Kim, Dae-Kweon ;
The Korean Journal of Malacology, volume 21, issue 2, 2005, Pages 113~120
In this experiment of natural Atrina pectinata spat collection, the number of the pen shell spats settled on a collector were 4.2, 6.8, and 2.7 in the first, second, and third year, respectively. The highest number of pen shell spat settled on the collector was observed in August, and the shell length of juvenile pen shells grew up to 42.5 mm six months after setting. The relation between shell length (SL) and days (D) after setting could be expressed as; SL = 0.3854D + 0.8423 (
= 0.9764). The spats developed the best in depth of 10-20 m. Spat collectors in mesh size of
mm were better for spats to survive than the ones in
. The most efficient material as substrate for the settlement of pen shell spat was a polyethylene monofilament in the spat collectors.
Changes in Biochemical Components of Several Tissues in Sinonovacula constricta, in Relation to Gonad Developmental Phases
Han, Ji-Soo ; Kim, Jong-Bae ; Lee, Chang-Hoon ; Chung, Ee-Yung ;
The Korean Journal of Malacology, volume 21, issue 2, 2005, Pages 121~132
We investigated the reproductive cycle with gonad developmental phases of Sinonovacula constricta by histological observations, and seasonal changes in biochemical component of the adductor muscle, visceral mass, foot muscle and mantle were studied by biochemical analysis, from January to December, 2004. The reproductive cycle of this species can be classifed into five successive stages: early active stage (March to May), late active stage (May to July), ripe stage (July to September), partially spawned stage (August to October) and spentfinactive stage (October to March). Total protein content was the highest in the following order: adductor muscle, visceral mass, foot muscle, and mantle. Except for mantle, it was generally higher during the ripe and spawning stages, while lower during the spent/inactive stage. There were positive correlations in total protein contents among adductor muscle, foot muscle, and visceral mass. However, the correlations were not statistically significant. Total lipid content was the highest in the visceral mass; it was more than 5 or 6-fold higher than those in the adductor muscle, foot muscle, or mantle. The monthly change was also most dynamic in the visceral mass. It first Increased during the early active stage (March to May), decreased during late active stage (May to July), and then increased again rapidly during the spawning stage (September). There were a strong negative correlation in total lipid contents between foot muscle and adductor muscle (r = -0.634, p = 0.027), and a strong positive correlation between adductor muscle and mantle (r = 0.665, p = 0.018). Glycogen contents showed more or less similar pattern to total lipid contents in the adductor muscle, foot muscle, and visceral mass. It was higher during the early active and spawning stages, while lower during the late active and spent/inactive stages. There was no statistically significant correlation in glycogen contents among different tissues. Especially, total lipid content showed a negative correlationship between the foot muscle, adductor muscle, visceral mass and mantle. Therefore, these results indicate that the nutrient content of the foot muscle, adductor muscle, viseral mass and mantle changed in response to gonadal energy needs.
Comparative Anatomy of the Family Bithyniidae (Prosobranchia : Mesogastropoda)
Kim, Jae-Jin ;
The Korean Journal of Malacology, volume 21, issue 2, 2005, Pages 133~145
Eight species of bithyniids, Bithynia leachi, B. tentaculata, B. siamensis, B. misella, B. kiusiuensis, B. striatula, Bithynia sp. from Nepal and Gabbia australis were collected from 1957 to 1988. The samples were relaxed with pentobarbital and fixed with 70% ethyl alcohol. There was no significant difference in internal structure of soft body, except the male reproductive system. The alimentary canal of the bithyniids consisted of mouth, buccal mass, esophagus, stomach, intestine, rectum and anus. The heart consisted of an auricle and a ventricle, located at left side of the stomach in the visceral hump. The ctenidium comprised 40-70 subtriangular lamellae. Eight ganglia were located around upper esophagus. The female reproductive system comprised ovary, oviduct, spermaaheca, and albumin gland. The male reproductive system was composed of testis, seminal vesicle, prostate gland, vas deferens, penial duct, and penis in order. Male was distinguished externally from the female by a bifid penis.
Molecular Phylogeny of Veneroidea (Bivalvia: Heteroconchia) on the Basis of Partial Sequences of 28S rRNA Gene
Kim, Sei-Chang ; Kim, Jae-Jin ; Hong, Hyun-Chul ;
The Korean Journal of Malacology, volume 21, issue 2, 2005, Pages 147~161
To elucidate the phylogenetic relation of the superfamily Veneroidea, we obtained partial 28S rRNA sequences of 14 heterodonts and three pteriomorphs which were collected from Korea and the sequence data of related taxa from GenBank, and analyzed maximum parsimony with PAUP program 750 of the nucleotide positions were variable, 560 of which were informative under conditions of parsimony. Total tree length was 2,765, and consistency index, homoplasy index (HI), and Retention index was 0.4843, 0.5157, and 0.6291, respectively. Intraspecific variation of 28 rRNA of Corbicula fluminea and Sinonovacula constricta was 3.1% and 1.3%, respectively. Pitarinae-Cyclininae-Meretrinae group had a clade and Samaranginae, Chioninae, and Dorsininae were clustered.