• Animal Systematics, Evolution and Diversity
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• v.8 no.2
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• pp.189-200
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• 1992

In the present investigation, some cluster analyses were done for each population of the native honeybee workers(Apis cerana), which were selected for 15 different localities in spring and 16 in summer from Korea. In this analysis, the seasonal segregation was perfectly revealed by both Ward's and the average linkage between groups methods, whereas, it did not necessarily revealed any systematic relationship between geographical groups.

• 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.11 no.4
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• pp.330-334
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• 2022

Mesorhabditis microbursaris (Steiner, 1926) Sudhaus, 2011, belonging to the family Mesorhabditidae (Rhabditomorpha), is newly reported from South Korea. During a survey of small streams, M. microbursaris was isolated from sedimentary soil samples. The genus Mesorhabditis Osche, 1952 nematodes are distributed all over the world and are mostly found from terrestrial habitats, however are sometimes found in freshwater. At present, 34 valid species have been recorded from Mesorhabditis; however, only three species have been reported from South Korea. Mesorhabditis microbursaris exhibits morphological characters of other congeneric species, including shorter distance between vulva and anus than the distance between anus and tail, rudimentary bursa with narrow velum and short genital papillae, shorter spicules than tail and conical tail. However, this species can be distinguished from other Mesorhabditis species by its morphometric characters and three pairs of bursal papillae. Details of the morphological characteristics and morphometrics of M. microbursaris are described and illustrated based on optical microscopy.

• Journal of Korean Neurosurgical Society
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• v.56 no.6
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• pp.475-481
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• 2014

Objective : To evaluate the anatomical feasibility of 3.5 mm screw into the cervical spine in the pediatric population and to establish useful guidelines for their placement. Methods : A total of 37 cervical spine computerized tomography scans (24 boys and 13 girls) were included in this study. All patients were younger than 10 years of age at the time of evaluation for the period of 2007-2011. Results : For the C1 screw placement, entry point height (EPH) was the most restrictive factor (47.3% patients were larger than 3.5 mm). All C2 lamina had a height larger than 3.5 mm and 68.8% (51/74) of C2 lamina had a width thicker than 3.5 mm. For C2 pedicle width, 55.4% (41/74) of cases were larger than 3.5 mm, while 58.1% (43/74) of pedicle heights were larger than 3.5 mm. For pedicle width of subaxial spine, 75.7% (C3), 73% (C4), 82.4% (C5), 89.2% (C6), and 98.1% (C7, 1/54) were greater than 3.5 mm. Mean lamina width of subaxial cervical spine was 3.1 (C3), 2.7 (C4), 2.9 (C5), 3.8 (C6), and 4.0 mm (C7), respectively. Only 34.6% (127/370) of subaxial (C3-7) lamina thickness were greater than 3.5 mm. Mean length of lateral mass for the lateral mass screw placement was 9.28 (C3), 9.08 (C4), 8.81 (C5), 8.98 (C6), and 10.38 mm (C7). Conclusion : C1 lateral mass fixation could be limited by the morphometrics of lateral mass height. C2 translamina approach is preferable to C2 pedicle screw fixation. In subaxial spines, pedicle screw placement was preferable to trans-lamina screw placement, except at C7.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.1
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• pp.77-84
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• 2017

Three species of pufferfishes (family Tetraodontidae) were examined to determine their morphological characteristics based on meristics, morphometrics, olfactory organs, and lateral line systems of specimens collected from the Chennai Fish Market in Tamil Nadu, India, in December 2016. The three species, which are all previously unreported in Korea, are Chelonodon patoca (Hamilton, 1822), Lagocephalus spadiceus (Richardson, 1845), and Arothron immaculatus (Bloch and Schneider, 1801). For nostril shape, fishes of the genus Lagocephalus have two nostrils, while Arothron and Chelonodon have none. Fishes of the genera Lagocephalus and Arothron have a single well-developed lateral line on the body, while Chelonodon fishes have two lateral lines that merge on the caudal peduncle.

• Animal Systematics, Evolution and Diversity
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• v.31 no.4
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• pp.277-283
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• 2015

Two pleurostomatid ciliates, Loxophyllum perihoplophorum Buddenbrock, 1920 and L. rostratum Cohn, 1866, were collected from the coastal waters of the East Sea, Korea. Their morphologies are described based on live observation and protargol staining, and morphometrics are provided. Loxophyllum perihoplophorum is characterized by the following features: 200-650 μm long in vivo; body slender leaf-shaped, flexible and contractile, with thin and wide extrusome-belted zone; 2 macronuclear nodules (Ma) and 1 micronucleus (Mi); 7-9 contractile vacuoles (CV) positioned along dorsal margin; extrusomes (Ex) evenly distributed along edge of entire body, with about 10 dorsal warts (Wa); 9-11 left (LSK) and 19-22 right somatic kineties (RSK), 4-5 furrows (Fu) on left side. Loxophyllum rostratum is about 100-130 μm long in vivo; body oblate leaf-shaped, contractile, convex ventral side and S-shaped dorsal side, beak-like anterior end; 2 Ma and 1 Mi; 1 CV terminally located; Ex distributed along edge of entire body, with about 9-10 dorsal Wa; 7-8 LSK and 15-19 RSK, ca. 5 Fu on left body side. In addition, sequences of small subunit ribosomal DNA were determined from these two Loxophyllum species and compared with the known Loxophyllum sequences.

• Animal Systematics, Evolution and Diversity
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• v.25 no.2
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• pp.167-178
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• 2009

Two poorly known and often confused pleurostomatid ciliates, Litonotus paracygnus Song, 1994 and L. pictus Gruber, 1884, were collected from the coastal waters of Yeonggeumjeong and Bongpo-port, Gangwondo in the East Sea and from the Iwon tide embankment near Ganwol-do, Chungcheongnam-do in the Yellow Sea, Korea. These species were described based on live observations, the protargol-impregnation and morphometrics of the species. Also provided are their diagnoses. The small subunit ribosomal DNA (SSU rDNA) sequences of these species were compared with previously known sequences of related species. The diagnostics of the two Litonotus species are as follows. L. paracygnus: 150-300 $\mu$m long in vivo, strongly contractile neck region, two ellipsoid macronuclei (Ma) and one micronucleus (Mi), 7 left (LSK) and 11-14 right somatic kineties (RSK), 2-4 contractile vacuoles (CV) located on the posterior end, extrusemes (Ex) distributed on the anterior region of the ventral margin only. L. pictus: about 200-600 $\mu$m long in vivo, extremely contractile, beautiful body color with rows of yellow to yellow-brownish cortical pigment granules, 12-21 Ma arranged in moniliform pattern, infrequently vermiform, 7-11 LSK and 18-26 RSK, several CV located on both margins, Ex distributed on the anterior region of the ventral margin only. In this study, this genus was firstly recorded in Korea.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.104-113
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• 1996

In order to clarify the interspecific variation of Astiphrom jezoense, a morphometric analysis was performed for seven populations using PCA (principle component analysis) and discriminant analysis. As a result of PCA, 25 quantitative characters are grouped into four factors. The characteristics on legs are especially important components both in male and in female. Morphometric analysis indicate that considerable morphological gap is correlated with geographical habitat. Important discriminant characters are MOD (maximum ocellar distance), Fn (first tergite length) in female and MSL (malar space length) in male.