• Korean Journal of Ichthyology
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• v.13 no.2
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• pp.111-116
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• 2001

Factors influencing elongation of the ovipositor in the bitterling Rhodeus uyekii were examined under several conditions. The ovipositors of the females were periodically elongated under the presence of mussels or males, and in some cases without either. When females were reared without mussels and males, the ovipositor did not elongate in one fish in a large aquarium, but it did become elongated in another fish in a small aquarium and in many fishes in a large aquarium. Duration of the elongated state of the ovipositor was 1~3 days (mean 1.2~2.5 days) and the periodicity of elongation was 4~15 days (mean 6.4~11.9 days). Length of the elongated ovipositor was 68~100% (mean 78.5~98.8%). Length of ovipositor in the interpeak period was 20~51% (mean 27.3~33.1%); in the post-elongation period it did not elongated further 3~30% (mean 11.1~19.9%). The effect of aquarium size and number of individuals in the aquarium on the elongation of the ovipositor, and inter-specific or inter-generic differences based on previous reports are discussed.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.554-562
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• 2020

Tremex fuscicornis (Siricidae), known as the xylophagous horntail, and Leucospis japonica (Leucospidae), known as the parasitoid wasp, are wood-boring wasps belonging to the order Hymenoptera. These insects are interesting sources of biological inspiration for the development of drilling mechanisms. To study the biomimicry aspects, the morphological characters of the ovipositor of T. fuscicornis and L. japonica were analyzed using a stereoscopic microscope, a field emission scanning electron microscope, and an optical microscope. There were many differences in the ovipositors between the two species, such as shape, length, surface structure, and arrangement of the teeth. Evenly arranged teeth were developed at the tip of both the dorsal valve and the ventral valve of the ovipositor of T. fuscicornis and looked like a rotating drill bit. In contrast, in L. japonica, the teeth, which looked like a saw, were found only on the ventral valve. Moreover, the tip of the ovipositor of T. fuscicornis was symmetrically divided into four parts, while that of L. japonica was divided into three parts having a 2:1:1 ratio. However, in the case of T. fuscicornis, after the 14th tooth, four parts melded into three parts maintaining a 2:1:1 ratio, and a dovetail joint was found on the horizontal cross-section of the ovipositor that allowed vertical movement for making a hole. These morphological differences of the ovipositor may be due to the insects' lifestyles and phylogenetic distance. Finally, zinc was commonly found at the tip of the ovipositors of both species, a probable result of ecological adaptation created by drilling wood.

• Korean Journal of Ichthyology
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• v.18 no.1
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• pp.27-35
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• 2006

During spawning season of female in a Korean oily bitterling, Acheilognathus koreensis, the ventral region near the base of the pectoral fin becomes to be protruded outward of body and enlarged. This ventral process consists of both organs as rectum (vent) and inner ovipositor. The rectum consists of mucosa, lamina propria-submucosa, muscularis, and squamous epithelial layer (peritoneum=serosa) surrounding them. The mucosa contains numerous mucous cells meaning acid mucopolysaccharides in nature. The inner ovipositor is similar to that of the rectum, but the mucosa have no mucous cell, unlike that of the rectum. Whereas, the outer ovipositor has a straight and long tube which are not connected with the ventral process any more. The outer ovipositor was similar to the structure of the inner ovipositor in the ventral process. However, the outer ovipositor has no muscularis, and consists of three layers: mucosa, lamina propria-submucoa, and squamous epithelia. The outer ovipositor without the muscularis seems serves as a tube that eggs discharged from the outer ovipositor allow to send inside mussel, unlike that of the inner ovipositor performing rhythmic contractions of the layers of the muscularies for propelling to the matured oocytes to the outer ovipositor.

• Korean Journal of Ichthyology
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• v.25 no.2
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• pp.74-81
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• 2013

Factors influencing spawning or respawning conditions of the bitterling, Acheilognathus signifer were investigated in the aquariums. Inducing the female spawning was more sensitive to the mussel than the male. The ovipositor of the female was periodically elongated and reduced from 4 to 6 days with the presence of mussel. During of the elongated state of the ovipositor was 1 to 2 days. As the result of natural spawning in the aquariums, it takes 1 to 3 days (mean 1.6) to spawn. The most important factor to respawn spawned females again was the mussel. It takes 11 to 53 days (mean 29.5) from extraction to reextraction of females which have elongated ovipositor. The egg numbers of reextraction were 2 to 41 (mean 19). This experiments showed the tendency the more standard length of females grows, the more the number of extracted eggs increases.

• Journal of the Korean Society for Nondestructive Testing
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• v.14 no.1
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• pp.23-31
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• 1994

Sound scattering by cylindrical tubes submerged in water is numerically analyzed with material attenuation considered. Complex wave numbers is introduced to see the effects of material attenuation on resonance scattering Backscattering pressures from the shells immersed in water are calculated for air-filled aluminium and acryl tubes. In order to investigate the resonance characteristics in detail, numerical analysis program has been completed which enables us to evaluate the effects of material attenuation. The testing of the program by comparison with previous results is reported and calculation results are compared and discussed for both aluminium and acryl tubes with material attenuation considered. The resonance peak and width is strongly affected by attenuation and this becomes severe as the peak is sharp and narrow and $k_{1{\alpha}}$ is high.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.233-240
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• 1991

A female Brachymeria lasus (Walker) was exposed to one or four pupae of host Hyphantria cunea Drury for 20 minutes within a petri dish $(1.5\times9cm)$ to learn factors influencing the host discrimination by the parasitoid. It rejected the parasitized host with its rejection ratio 73.3% for the one pupal exposure vs 100% for the four pupal exposure scheme. The parasitoid could discriminate the parasitized host by its antennal drumming and ovipositor probing due to a pheromone-like external marking which is effective only for a certain peiod of time, and a host quality associated with the parasitoid development, respectively.

• The Science & Technology
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• no.11 s.438
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• pp.50-53
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• 2005

몸이 세로로 납작한 소형 민물고기인 납자루 아과(Acheilognathinae) 어류는 잉어과에 해당하며 전세계에 40여 종이 알려져 있다. 우리 나라에는 이미 멸종된 서호납줄개를 포함하여 납줄개속, 납자루속 및 큰납지리속의 3속 14종이 있으며, 그 중 8종은 우리 나라의 고유종이다. 수컷은 화려한 혼인색을 내고 암컷은 산란관을 내어 민물조개에 산란하는 특성이 있다.

• Proceedings of the Korean Aquaculture Society Conference
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• 2006.05a
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• pp.603-604
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• 2006

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2004.05a
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• pp.65-65
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• 2004

• Journal of Sericultural and Entomological Science
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• v.13 no.2
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• pp.119-122
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• 1971

The following results were obtained through the experiments and study of fertility for silkworm eggs in vagina, oviduct, and ovarial base. The sample eggs were collected after leaving silkworm moth for one week from the date of treatment was given to oviporm orifice of the silkworm moth by heated needle in order to discontinue laying eggs. Those sample silkworm moths were divided into two groups. The first group was under the condition of immediately after the couplation and the second group was under the condition of after the laying eggs in some extend, and both of them were completed couplation. The sample eggs were screened in order to confirm the degree of color which normally be observed as very characteristic during hibernating. 1. About 5% of silkworm out of the total sample were identified as having 1-2 eggs. (See table 1). But, the charasteristic colour of hibernating egg was not observed. The colour was not much different as that of eggs in ovarian duct. 2. Immediately after the couplation, the eggs were not found in vagina under the condition of immediately after the couplation. 3. About 10% of the sample under the condition of after laying eggs in some extend were found having eggs in vagina or oviduct. 4. About 2% of the sample silkworm moth under the condition of immediately after the couplation were found having I fertilized egg in oviduct. 5. No fertilized egg was found in ovarian tube. It seemed that sperm did not enter ovarian tube. 6. Almost the entire eggs were found in ovarian tube under the condition of immediately after the couplation. But, eggs under the condition of after laying eggs in some extend were found around oviduct and vagina due to the continuous movement of silkworm eggs towards oviporus orifice. 7. Sperm is mainly found around seminal receptacle and vagina, and sperm goes into micropyle together with silkworm eggs which were moving towards oviduct.