• The Korean Journal of Malacology
• /
• v.5 no.1
• /
• pp.29-34
• /
• 1989

의암호에서 채집된 작은애칭이(Anodonta aracaeformis)와 펄조개(Anodonta woodiana despecta)의 유생을 줄납자루(Acheilognathus yamatautae), 돌고기(Pungtungia heizi), 붕어(Carassius auratus)를 숙주로 하여 인위 감염 시킨 결과는 다음과 같다. 1. 펄조개 glochidium 의 부착기간은 줄납자루, 돌고기에 각각 10일과 9일이었고 작은대칭이glochidium은 붕어에 21일간 부착하였다.2. 펄조개, 작은 대칭이 glochidium은 숙주의 가슴지느러미와 아가미에 높은 부착률을 나타내었다.3. 펄조개glochidium의 부착전과 후의 크기 변화는 없었으나 작은 대칭이 glochidium의 경우는 각고, 각장, 인대길이의 부착전 평균 크기가 0.345mm, 10365mm, 0.271mm에서 21일 이후 이탈 직전의 평균 크기는 0.373mm, 0,386mm, 0.290mm로 외형적인 크기 증가를 나타내었다.4. 펄조개 glochidium감염에 대한 숙주의 민감성은 줄납자루가 돌고기보다 높게 나타났다.5. 펄조개 glochidium은 부착후 2일, 작은대칭이는 8일째부터 기관 형성을 관찰할 수 있었다.

• The Korean Journal of Malacology
• /
• v.5 no.1
• /
• pp.1-9
• /
• 1989

A scanning electron microscopic study on the glochidium and glchidial encystment of Anodonta grandis on the guppy was conducted. The shape of the glochidium is apparently triangular and its averge size is 0.45mm X0.4mm when closed, The two glochidial shell valves are of the same size, kept together by a ligament of 120${\mu}{\textrm}{m}$ in length and 7 ${\mu}{\textrm}{m}$ in width. Each of the glochidial shell valves has a 16 ${\mu}{\textrm}{m}$ long hook sitdded with many spines on the superior face. A large area to the apex of the valve surrounding the base of the hook is provided with numerous small spines which become progressively smaller towards the periphery of the area, The external surface of the glochidial shell valve is covered with numerous small processes showing successive change in the shape and the pattern of destribution by part. Besides the processes, there are a number of niches scattered all over the exterior surface. The glochidial shell valve has two layers. One is the outer thin membrane bearing the processes and the niches and the others is the inner layer bearing numerous holes which any accessory structure and 2.65 ${\mu}{\textrm}{m}$ in diameter, emerges from a canal located at center of ventral plate of the mamtle, A total of three types of the hair cells are observed. In present artificial infection of the glochidium to the guppy, it took about three to four hours to complete an early cysts, During the period of encystment, The epithelial cells of the host fish actively migrated toward the attached glochidium and covered it.

• The Korean Journal of Malacology
• /
• v.2 no.1
• /
• pp.26-29
• /
• 1986

Corbicula fluminea, one of the 2 species in the family Corbiculidae living in the Lake Uiam, was used as an experimental material and the embryonic development and the structure of glochidia of this species were investigated. This freshwater mussels was oviparous, but some ovoviviparous: incubated their youngs in the inner-demibranchs or outer-demibranchs, however, chiefly used the inner-demibranchs as brood-pouch. The average time required from a fertilized egg to two-cell stage, veliger stage, and glochidium was 76 minutes, 3 hours, and 17 hours, respectively, The mean size of glochidium was $168{\mu}m$ in shell height, $195{\mu}m$ in shell lengh, $114{\mu}m$ in hinge legth and the form of glochidium was D-type and had no hooks or hooklets for attaching to fish like Unioidae.

• Proceedings of the Korean Society of Fisheries Technology Conference
• /
• 2001.05a
• /
• pp.595-596
• /
• 2001

A scanning electron microscopic study on the glochidium and glochidial encystment of Anodonta archefomis on the host fish Carassius auratus was conducted. The shape of the glochidium is apparently subtriangular and its average size is 270${\mu}{\textrm}{m}$ $\times$ 260${\mu}{\textrm}{m}$ $\times$ 145${\mu}{\textrm}{m}$. The glochidial shell valves are of the same size, kept together by a ligament of 50.4${\mu}{\textrm}{m}$ in length and 5.5${\mu}{\textrm}{m}$ in width. (omitted)

• The Korean Journal of Malacology
• /
• v.23 no.2
• /
• pp.181-187
• /
• 2007

A scanning electron microscopic study on the glochidium and glochidial encystment of Anodonta arcaeformis on the host fish Carassius auratus was conducted. The shape of the glochidium was apparently subtriangular and its average size was $270\;{\mu}m\;\times\;260\;{\mu}m\;\times\;145\;{\mu}m$. The glochidial shell valves were of the same size, kept together by a ligament that is 50.4 ${\mu}m$ in length and 5.5 ${\mu}m$ in width. Each of the glochidial shell valve had a long hook studded with many spines on the superior face. A large area of at the apex of the valve surrounding the base of the hook was provided with numerous small spines which became progressively smaller toward the periphery of the area. The glochidial shell valve consisted of two layers. The mantle cells line the glochidial shell valves and some of hair cells were observed. A larval thread was 2.3 ${\mu}m$ in diameter. In the artificial infection of the glochidia to one of the natural hosts, Carassius auratus, it took about three to four hours to encyst the glochidia with epithelial cells of the fish fins. The encystment method was the cell migration from the neighboring epithelial cells.

• The Korean Journal of Malacology
• /
• v.7 no.1
• /
• pp.76-86
• /
• 1991

A scanning electron microscopic stuey on the glochidial encystment study on the golchidal encystment and excystment of Anodonta fukudai on Acheilognathus yamatsutae, a common natural hostfish, was conducted. The glochidium easily attached to the unscaled surfaces of the host fish such as the fins, lips, and the wall of the buccal cavity. For this study, the fins infected with the glochidia wer mainly observed in a series. The process of encystment was slowly progressed, for 21-25 hours for the early cyst and for 2-4 days for the thick walled cyst. The process of excystmint was visually detected on the 12th day since the attachmint was occurred. The first visible sign was a little tear of the cyst wall covering the hinge and marginal zones of the juvenile clam and once the little sign was appeared the progress of emerging and dettachmint of the juvenile clam from the host was finished relatively in short time. During the process of the encystmint, the cells participationg in covering the attached glochidirm were seened mainly supplied by migration from the surroundings. the shapes of the cells migrating and covering the glochidium were considerably changed and the surface structures of the cells lost their normal pattern of the surface ridges. The unstable forms of the cells were observed almost all throughout the period of the glochidial attachment. No cells of the host epithelium, which were still attached to the juvenile clam energing from the cyst, were observed. The most juvenile clams escaped from the cysts were a little bigger than the glochidia and they were still possessed of the golchidial hooks even though much degenerated. The first growth line was appeared on the shell valves of the juvenild clam when observed right after dettachment.

• Korean Journal of Ichthyology
• /
• v.26 no.2
• /
• pp.83-88
• /
• 2014

An endemic Korean bitterling, Acheilognathus signifer, known as using freshwater mussels for its spawning activity, much prefers Lamprotula leai in Dalcheon stream (Goesan population) and Unio douglasiae sinuolatus in Gadaecheon (Danyang population) stream, Korea. The spawning pattern between two mussels and one bitterling was carried out in two populations from April to June, 2011 and 2013. L. leai in the Goesan population was bigger shell length and have more eggs, larvae or both with A. signifer than those of U. d. sinuolatus in the Danyang population. Also, A. signifer in the Goesan population appeared to have a longer ovipositor and lay ripen eggs more than those of A. signifer in the Danyang population. Glochidium, a larval stage, of some L. leai in the Goesan population was incubated in all the demibranch, whereas for all of U. d. sinuolatus in the Danyang population was found in the outer demibranch only. For L. leai in the Goesan population, the eggs, larvae or both of A. signifer were much more in the non-breeding mussels (giving no glochidium) than the breeding mussels having the glochidium. For U. d. sinuolatus in the Danyang population, in contrast, the non-breeding mussels have fewer eggs, larvae or both less than the breeding one.

• Development and Reproduction
• /
• v.2 no.1
• /
• pp.81-87
• /
• 1998

A scanning electron microscopic study on the glochidial encystment and excystment during the development of Anodonta arcaeformis flavotincta on Carassius auratus, a common natural host fish, was carried out. The glochidia were attached to the fins, buccal cavity and gills of the host fish within 30 minutes. In this study, the fins of host fish infected with the glochidia were examined in a time series. The attachment rates of the glochidia on the pectoral fins, caudal fin and pelvic fins of the host fish were 30%, 22%, and 17%, respectively. The glochidia which attached to the fish became encysted within 27 hrs. The process of encystment progressed slowly. Ti took 24 to 27 hours in the formation of the primary cyst, and after 5 to 6 days, the larvae was covered completely with the epithelial cels of the host tissues. The process of detachment of juvenile clam was observed on the 8th day after host infection. Most of the juvenile clams have sloughed from the cyst of the host within 15 days. No significant size difference was observed in the glochidia and the juvenile which were found before attachment and after detachment from the cyst of the host fish.