• Korean Journal of Environmental Biology
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• v.21 no.3
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• pp.271-275
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• 2003

The direct count and MPN (Most Probable Number) methods were used to measure the number of nematodes in soils collected from cultivated and non-cultivated fields. As a result, the number of nematodes from cultivated soils was higher than the non-cultivated soils (NC -1, NC -2). On the other hand, upon measuring the value from the organo farming cultivated soils (OC, OR) and conventional cultivated soils (CC, CR), the former showed 16 times higher than the latter. These results indicate that nematode population which can multiply in the organic compounds abundantly exist in the organo farming cultivated soil. Isolated entomopathogenie nematodes are composed of two orders, which were Rhabditida and Diplogasterida. To determine the pathogene-city of them using the 5th larvae and pupae silkworm, and the following mean $LD_{90}$ values were found: 24 to 30 hours in Rhabditida and 36 to 48 hours in Diplogasterida nematode, respectively. This study indicates that nematodes are sensitive to this kind of environmental disturbance. Isolated entomopathogenic nematodes were suggested that aye quite within the realms of possibility for biological control agents.

• Journal of Species Research
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• v.8 no.3
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• pp.259-267
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• 2019

Five free-living nematode species belonging to the order of Rhabditida are described for the first time in Korea. Two unrecorded species of Rhabditidae, Cruznema tripartitum (Linston, 1906) Zullini, 1982, and Poikilolaimus oxycerca de Man, 1895, and one species of Peloderidae, Pelodera strongyloides Schneider, 1860, were collected in Korea. C. tripartitum has nine pairs of genital papillae arranged in 2+2+1+4 differently from similar species of C. scarabaeum which has ten genital papillae arranged in 2+1+4+3. Poikilolaimus oxycerca has shorter tail (shorter than anal body diameter) compared to similar species of P. regenfussi which has longer tail(longer than anal body diameter). Pelodera strongyloides has shorter tail(1-1.5 times anal body diameters long) than P. punctata (4 anal body diameters long). Two unrecorded species of Panagrolaimidae, Panagrolaimus apicatus Schuurmans Stekhoven & Teunissen, 1938 and Panagrolaimus rigidus (Schneider, 1866) Thorne, 1937 were collected in Korea. P. apicatus has rounded and lower lip compared to similar species, P. margaretae Massey, 1964 which has finely pointed lip. P. rigidus has slender tail and lips rounded and flat barely separated when compared to similar species, P. subelongatus(Cobb, 1914) Thorne, 1937 which has plumper tail and lips are well separated.

• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.321-330
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• 1999

Nematodes were isolated using silkwom trap through the investigation of 100 soil samples from various biotopes in Korea. The 30 nematode strains from soil and dead insects by the pathogenicity aganinst silkworms (Bombyx mori mori) and insect pests of Calliphora vomitoria, Pseufazetia separata, Palomena angulosa, and Melolontha incana. Mortailty of the silkworm larvae and pupae were as high as 100% by nematode infection, those of insect of pests were varied from 20 to 100%. The 30 strains of entemopathogenic nematodes were classified into five groups of Rhabditidae, Diplogatroidae, Heterorhabitidae, Steinernematidae, and Tylenchida by morphological criteria. The genetic relationships among the 30 nematode strains were analyzed by various RAPD bands with twenty primers. The 30 nematode strains were classified into six major subgroups on the basis of the genetic similarity coefficient of 0.853. The grouping by RAPD was agree with those of morphological taxa in discrimination of the higher group, however, was not completely agree in the subgroup. The family Steinernematidae belong to Rhabditida was clarified as closer to the Tylenchida, rather than the other Rhabditida of Heterorhabitidae, Rhabditidae, and Diplogatroidae in genetic distance valule. From the result of the morphological classification and RAPD of the genomic DNA showed that genetic relationship analysis furnish infurmation on phylogenetic classification and relationships of entomopathogenic nematodes. The application of genetic similarity will overcome the limitation of taxonomy and classification of morphologically simple nematode. Several primers were confirmed those utility of identification for individual nematode strains, the methods of molecular genetics secured the simplicity, rapidity and accuracy on the selection of entomopathogenic nematodes.

• Journal of Species Research
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• v.6 no.2
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• pp.177-180
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• 2017

Diploscapter coronatus (Cobb, 1893) Cobb, 1913 was first reported on oriental melon (Cucumis melo vars. makuwa Makino) roots from plastic film houses, Gyeongsangbuk-do, Andong, Korea (latitude $N36^{\circ}33^{\prime}$. longitude $E128^{\circ}29^{\prime}$). Diploscapter coronatus is most similar to D. pachys. Species in the genus Diploscapter have a visibly annulated cuticle. The stoma of D. coronatus is 1.5 times longer than the lip region width. The pharyngeal corpus is clearly separated from the isthmus and the vulva is situated around the mid-body. However, it differed by higher ratio of "a", filiform tail and had relatively blunt labial hooks. The Korean population is well matched and within the range of D. coronatus as described from Iran and Ethiopia in de Man's of L, b, c, c', and V. Female length, however, varied between populations: the Ethiopia population female length is longer than in the Korea population (396.4 vs 427.0) while females in the Iran population are smaller than in the Korea population (396.4 vs 350.0). Nematode size may vary due to environmental conditions such as food sources. The position of excretory pores in the Korean population were shorter 53.9-72.5 than in other populations (67-82 and 70-89). Males were uncommon. Males in the Korean population are smaller than females but larger(356.0) than males in the Indian population (306.0).

• Animal Systematics, Evolution and Diversity
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• v.33 no.4
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• pp.256-261
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• 2017

Eucephalobus oxyuroides (de Man, 1876) Steiner, 1936 belonging to the family Cephalobidae Filpijev, 1934 (Cephalobomorpha) is newly reported from South Korea. This species is distinguished from other Eucephalobus species by its pointed tail terminus, high lips and relatively longer female tail and body. From many previous studies, intraspecific variation in this species has been reported for body length, absence/presence of probolae, and number/position of papillae in the posterior region of male, posing an obstacle for identification and phylogenetic analysis. In this study, details of the morphological characters and morphometric of E. oxyuroides Korean population are described and illustrated based on optical microscopy.

• Animal Systematics, Evolution and Diversity
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• v.32 no.4
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• pp.258-265
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• 2016

Acrobeloides nanus (de Man, 1880) Anderson, 1968 belonging to the family Cephalobidae Filpijev, 1934 (Cephalobomorpha) is newly reported from South Korea. This species is distinguished from other Acrobeloides species by its low and blunt labial probolae, five lateral incisures with middle incisure extending to the tail tip, and bluntly rounded tail. In this study, details of morphological characters of A. nanus is described and illustrated based on optical and scanning electron microscopy. In addition, molecular sequence data of the D2-D3 region of 28S rDNA, 18S rDNA and mitochondria DNA cox1 region from this species are provided as DNA barcode sequences.

• Animal Systematics, Evolution and Diversity
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• v.37 no.4
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• pp.345-348
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• 2021

The genus Eucephalobus Steiner, 1936, belonging to the family Cephalobidae Filipjev, 1934 (Cephalobomorpha), represents a group of bacterial feeding nematodes. Although this group is cosmopolitan and species-rich, only two species have been reported from South Korea. Eucephalobus iaculocaudatus Bostrom and Holovachov, 2011 was collected from natural forest in Chungcheongbuk-do, South Korea. This species shows typical morphological characters of the genus Eucephalobus, including a bicornuate labial probolae, cephalic probolae absent and three lateral incisures. However, E. iaculocaudatus is distinguished from other Eucephalobus species by conoid tail with a harpoon-shape mucro in female and ragged mucro in male. In this study, detailed morphological characters and morphometrics of E. iaculocaudatus are described and illustrated based on optical microscopy.

• Animal Systematics, Evolution and Diversity
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• v.35 no.3
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• pp.95-104
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• 2019

The family Mesorhabditidae $Andr{\acute{a}}ssy$, 1976 is the most abundant group in Rhabditoidea and occurs all over the world. Over 85 valid species have been reported from Mesorhabditidae; however, only 2 species have been recorded in South Korea. In this study, Bursilla vernalis $Andr{\acute{a}}ssy$, 1982, Mesorhabditis inarimensis (Meyl, 1953) Dougherty, 1955, and M. minuta $Bostr{\ddot{o}}m$, 1991 belonging to the family Mesorhabditidae (Rhabditomorpha), are newly reported from South Korea. Species in this family are distinguished from other rhabditomorphs by a posteriorly located vulva and an unpaired prevulval female gonad. Details of the morphological characters and morphometrics of B. vernalis, M. inarimensis, and M. minuta are described and illustrated based on optical and/or scanning electron microscopy.

• Animal Systematics, Evolution and Diversity
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• v.35 no.2
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• pp.41-48
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• 2019

Pseudacrobeles(Pseudacrobeles) variabilis(Steiner, 1936) Steiner, 1938 and P. (Bunobus) pseudolatus($Hern{\acute{a}}ndez$, 1990) De Ley, Siddiqi and $Bostr{\ddot{o}}m$, 1993 belonging to the family Cephalobidae Filipjev, 1934 are newly reported from South Korea. Pseudacrobeles (Pseudacrobeles) variabilis is distinguished from its congeners by having distinctly setiform cephalic probolae, three rounded or knob-shaped labial probolae and longer female tail. Pseudacrobeles (Bunobus) pseudolatus is distinguished from its congeners by having visibly lateral lips, a short post-uterine sac, elongated conoid tail in the female, and acute mucro on the tails of both sexes. In this study, details of the morphological characters and morphometrics of Korean populations of P. (P.) variabilis and P. (B.) pseudolatus are described and illustrated based on optical microscopy.

• Journal of Species Research
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• v.10 no.4
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• pp.405-411
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• 2021

The genus Acrobeloides(Cobb, 1924) Thorne, 1937 are bacterial feeders and are one of the most abundant and widely distributed nematode groups in various terrestrial environments. Based on morphological and morphometric analyses, we found two Acrobeloides species reported in Korea for the first time: A. bodenheimeri (Steiner, 1936) Thorne, 1937 and A. tricornis (Throne, 1925) Thorne, 1937. These species exhibit morphological characters concordant with typical features of the genus Acrobeloides, such as a fusiform pharyngeal corpus with swollen metacorpus and lateral incisures extending to the tail terminus. However, A. bodenheimeri is distinguished from other acrobeloids by having its low and rounded labial probolae, distinct post-uterine sac and five lateral incisures. Acrobeloides tricornis is distinguished from its congeners by the following characteristics: its high labial probolae with acuate termini, inconspicuous post-uterine sac and five lateral incisures. Morphological characters and their measurements, and illustrations of A. bodenheimeri and A. tricornis are described in this study.