• Animal Systematics, Evolution and Diversity
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• v.17 no.1
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• pp.35-47
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• 2001

The postembryonic development of the Korean crayfish, Cambaroides similis (Koelbel, 1892), was described in detail and compared with those of other known species of Astacidae and American Cambaridae, and phylogenetic relationship of the genus Cambaroides was discussed. Ovigerous females of the Korean crayfishes appear in May. Durations of juvenile stages 1 and 2 are two and four weeks at 15.0 $\pm$ 0.5$^{\circ}C$, respectively. From juvenile stage 3, it leaves from its mother. It is considered that C. similis is very closely related more to the Astacidae than to the Cambaridae in the characteristics of the maxillule of juvenile stage 1 and the antenna, maxilla, pleopod, and telson of juvenile stage 2.

• Journal of Aquaculture
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• v.22 no.1
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• pp.16-22
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• 2009

Life history of Korean crayfishes Cambaroides similis (Koelbel) was studied 8 month from March to October, 2006 from the Gwanak mountain, Seoul, South Korea. By capture and recapture method, 551 crayfishes were collected analyzed during the experimental period. Based on the distribution pattern of body lengths, the local population putatively divided into four age groups. The sex ratio of male and female was almost equal. However, their growth rates varied by water temperature. Early juveniles seen during June became adult during August. The study findings suggest that late autumn is mating season.

• Parasites, Hosts and Diseases
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• v.37 no.1
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• pp.55-57
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• 1999

During the period from October 1996 to November 1998, the infection status of Paragonimus westermani metacercariae in freshwater crayfish (Cambaroides similis) collected from Bogildo (islet), Wando-gun, Chollanam-do, which is known for an endemic area of P. westermani in Korea, were examined. The average infection rate of Paragonimus metacercariae in crayfish was 88.6%, and mean number of metacercariae per infected crayfish was 30.2. This metacercarial density was the highest in the group of weight in 7.1-9.0 g. These results suggest that the natural life cycle of P. westermani is still well-preserved in Bogildo.

• Animal cells and systems
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• v.15 no.1
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• pp.37-43
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• 2011

The Korean freshwater crayfish, Cambaroides similis, has recently suffered from range reduction and habitat degradation caused by environmental changes and water pollution. For the conservation and restoration of this species, it is necessary to understand the current population structures of Korean C. similis using estimation of their genetic variation. In this study, eight micro satellite loci were developed and characterized from 49 individuals collected from four locations: one population from Mt. Bukhan (BH) and three populations from Mt. Gwanak (GA) in Seoul, Korea. As a result, the number of alleles per locus ranged from 2 to 12. The observed heterozygosities and expected heterozygosities ranged from 0.000 to 0.833 and from 0.125 to 0.943, respectively, and the former values were significantly lower than the latter ones expected under the Hardy-Weinberg equilibrium. No significant linkage disequilibrium was revealed between any of the locus pairs after Bonferroni correction. From the pairwise Fst results over all samples, higher differentiation between GA-BH population pairs (mean 0.1789) was observed than between GA population pairs (mean 0.0454). This was also supported by Mantel's test showing that the genetic distances of these crayfish populations were significantly correlated with geographic distances. This result may show the regional differentiation caused by restricted gene flow between northern (BH) and southern (GA) populations within Seoul. These micro satellite markers have the potential for use in analyses of the genetic diversity and population structure of C. similis species, with implications for its conservation and management plans.

• Proceedings of the Korean Aquaculture Society Conference
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• 2001.12a
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• pp.235-237
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• 2001

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.128.3-128
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• 2003

• Journal of Ecology and Environment
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• v.47 no.4
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• pp.200-210
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• 2023

Background: Cambaroides similis is an endangered candidate species living in the stream of South Korea. Freshwater crayfish is known to decline rapidly not only domestically, but also internationally. Its decline is projected to be further exacerbated due to climate change. Understanding physical characteristics of the habitat is crucial for the conservation of an organism. However, comprehensive data regarding the distribution and physical habitat characteristics of C. similis are currently unavailable in South Korea. Thus, the objective of this study was to ascertain preferred ranges for water depth, current velocity, and streambed substrate of C. similis using Weibull model. Results: In this study, C. similis was found at 59 sites across 12 regions in South Korea. Its optimal water depth preferences ranged from 11.9 cm to 30.1 cm. Its current velocity preferences ranged from 9.8 cm s^-1 to 29.1 cm s^-1. Its substrate preferences ranged from -5.1 𝜱_m to -2.5 𝜱_m. Median values of central tendency were determined as follows: water depth of 21.4 cm, current velocity of 21.2 cm s^-1, and substrate of -4.1 𝜱_m. Mean values of central tendency were determined as follows: water depth of 21.8 cm, current velocity of 22.0 cm s^-1, and substrate of -4.4 𝜱_m. Mode values of central tendency were determined as follows: water depth of 21.7 cm, current velocity of 20.1 cm s^-1, and substrate of -3.7 𝜱_m. Conclusions: Based on habitat suitability analysis, physical microhabitat characteristics of C. similis within a stream were identified as Run section with coarse particle substrate, low water depth, and slow current velocity. Due to high sensitivity of these habitats to environmental changes, prioritized selection and assessment of threats should be carried out as a primary step.

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.110.3-110
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• 2000

No Abstract, See Full Text

• Journal of fish pathology
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• v.19 no.2
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• pp.141-153
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• 2006

Genomic DNA samples isolated from two geographical crayfish (Cambaroides similis) populations in the inland of the Korean Peninsula, at Jeonju (Jeonju crayfish; JJC) and Jeongup (Jeongup crayfish; JUe), were PCR-amplified repeatedly. The six arbitrarily selected primers OPC-03, OPC-06, OPC-09, URP-02, URP07 and URP-09 generated the common, specific, and polymorphic fragments. The sizes of DNA fragments also varied widely, from 100 bp - 2,600 bp. Here, 521 fragments were identified in the JJC population, and 354 in the JUC population: 6 primers generated 60 specific fragments (60/521 fragment, 11.5%) in the JJC population, and 90 (90/354 fragments, 25.4%) in the JUC population. These primers produced 42 polymorphic fragments (8.1%) in the DC population, and 18 (5.1%) in the mc population. Especially these results demonstrate that the primers detected numerous specific fragments. Especially, the decamer primer OPC-06 generated inter-population-common DNA fragments, approximately 400 and 800 bp, respectively, in both the JJC and JUC populations. The universal primer URP-02 also generated inter-population-identical DNA fragments, approximately 350 bp and 600 bp, between the two geographical crayfish populations. Based on the average bandsharing values of all samples, the bandsharing value of individuals within the JJC population was much higher than in the JUC population. The bandsharing value between individuals no. 10 and no. 15 was 0.683, which was the highest between the two geographical populations. The dendrogram obtained by the six primers indicates two genetic clusters: cluster I (CRAYFISH 01 - CRAYFISH II), and cluster 2 (CRAYFISH 12 - CRAYFISH 22). The genetic distance between the two geographical populations ranged from 0.053 to 0.605. Ultimately, the longest genetic distance displaying significant molecular differences was found to exist between individuals in the two crayfish populations, between individuals CRAYFISH no. 02 of Jeonju and CRAYFTSH no. 15 of Jeongup (genetic distance = 0.605).

• The Korean Journal of Zoology
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• v.34 no.3
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• pp.338-351
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• 1991

The analysis of the absolute growth in seven body parts of crayfish (Cumbaroides similis Koelbel), such as carapace length, carapace width, abdominal length, abdominal width, sheliped length, second pereiopod length and third pereiopod length (the grolwth formula, y : a + bt ~ci applied) was performed. The results obtained are as follows: 1. The analyses of changing growth quantity for the seven body parts in both sexes showed concave shaped increase. 2. The largest ratios of the grourth quantity in both sexes were revealed in abdominal width (18.3677 times in male and 18.9253 times in female). 3. The srolwth rates of the seven body parts in both sexes showed a smooth increasing pattern. 4. 각B the sperifn'cgrouch rates revealed a decreasing pattern, moreover steep descendent patterns of it appeared in abdominal length of both sexes and abdominal width in male.