• Animal Systematics, Evolution and Diversity
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• v.5 no.1
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• pp.77-88
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• 1989

Genetic and morphometric comparison between two species of the genus Agkistrodon were performed to estimate the degree of genic variation and to clarify the taxonomic status of Cheju population, a suspected hybrid form between A. blomhoffii brevicaudus and A u ussuriensis. A sum of 147 specimens representing six populations of A.b. brevicaudus and two populations of A ussuriensis was used in this study. Out of the 21 loci examined, 5 loci (Adh, Ldh-2, Mdh-2, Mpi, Pgi) were monomorphic with identical mobility in both species. O Other Sioci (Aco, Gp, Fum, [po and Xdh in A b. brevicaudus; Est, Got-l, Gp, Mdh-l and 6Pgd in A ussuriensis) were highly poplymorphic. The degree of genic variation of Ab. b brevicaudus and A ussuriensis was A=1.SS, P=42.1%, HD=0.096, HG=O.l1S, and A= 1.4S, P = 31.6%, HD=0.117, HG =0.121, repectively. These values are twofold higher t than those of other reptilian species reported (Selander, 1976) including Korean species of Rhabdophis tigrina and Elaphe dione (Paik and Yang, 1986, 1987). The average values of t the genetic similarities among six populations of A b. brevicaudus and two populations of A ussuriensis were S=0.919 and S=0.962, respectively, whereas the value between species was S = 0.662. Presumed divergent time estimate (Nei, 1975) of these two species was about 1 1.8 million years ago. The analysis of the geographic variations of various morphological c characters was based on Gloyd’s criteria (Gloyd, 1972). Coloration of tongue and tail tip, t the number of ventral scales, and the number of subcaudal scales are good diagnostic c characters to identify these two species. The pattern of cross band is, however, highly variable within and between populations of both species. No hybrid was detected and the s suspected hybrid form of Cheju population falls within the range of A. ussuriensis in the g genetic and morphometric analyses.

• Animal Systematics, Evolution and Diversity
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• v.17 no.1
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• pp.49-57
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• 2001

The partial sequences of mtDNA cytochrome b gene in two subspecies of striped field mouse(Apodemus agrarius coreae and A. agrarius manchuricus) from Korea and northeast China were analyzed to determine the degree of genetic diversity in ech subspecies and to confirm their subspecific difference. In 18 specimens of A. agrarius coreae, ten haplotypes were resulted, and in two specimens of A. agrarius manchuricus. one haplotype was revealed. Tamura-Nei nucleotide distance among ten haplotypes in subspecies coreae ranged 0.36 to 1.86%. and nucleotide distance between two subspecies (coreae and manchuricus) was 0.37 to 1.47%: maximum infrasubspecific divergence in coreae was greater than maximum intersubspecific difference between two subspecies. Moreover, no major subgroup was resulted when 11 haplotypes in two subspecies were compared. Our sequence result was not cancordant with the morphological data studied so far, and it is concluded that cytochrome b gene sequence is not a good genetic marker to distinguish two subspecies of A. agrarius. In futurem, mtDNA control region analyses seemded to be necessary to reveal genetic relationship between these two subspecies of A. agrarius.

• Animal Systematics, Evolution and Diversity
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• v.5 no.2
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• pp.107-119
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• 1989

Three species of Korean sticklebacks family Gasterosteidae were reviewed based on the specimens of several populations for the study of their morphological variations and taxonomical positions. All specimens of Gasterosteus aculeatus observed have a complte row of lateral plates ranging from thirty-two to thirty-five in number. The low-plate morph regarded as landlocked type is virtually absent. And no difference was recognized among six populations of G. aculeatus in the meristic chracters, i.e. number of vertebrae, gill rakers and finrays. The Pungitius sinensis and P.kaibarae ssp. shown local variations have scutes ranging from 31 to 35, but not clinal in the morphometric characters. But P.sinensis was statistically different from P.kaibarae ssp. in some characters such as the number of dorsal spine rays and vertebrae, and body depth, although their ranges overlapped. No significant taxonomic difference was detected between white from and black from in dorsal spinous membrane of P.kailbarae ssp. Although these three species of Korean sticklebacks have the same diploid chromosome number (2N=42), G. aculeatus is obviously different from the two species of genus Pungitius in their karyotype ; G. aculeatus consists of six metacentrics, six submetacentrics, and thiry subtelo-acrocentrics, and both P.sinensis and P.kaibarae ssp. have four metacentrics, six submetacentrics, and thirty-four subtelo-acrocentrics.

• Animal Systematics, Evolution and Diversity
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• v.16 no.1
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• pp.125-131
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• 2000

This paper deals with the morphology and taxonomy of the first reported species of echinostome belonging to the genus Himasthla Dietz, 1909, found from dunlins (Calidris alpina sakhalina) in Korea. Birds were captured with mist-nets at the tidal flat of Yeochari, Kanghwa-gun, Kyunggi-do, Korea. The worms were removed from avian intestines in physiological saline, fixed, acetocarmine stained and observed. Himasthla kusasigi Yamaguti, which was found in 1939, was characterized morphologically by a long and slender body (5.27 mm in length), besetting with spines and reniform head collar (0.27 mm) in a form of a single and uninterrupted row of 31 spines. The oral sucker (0.057$\times$0.0684 mm) is smaller than the ventral sucker (0.35$\times$0.29 mm). The ventral sucker was close to the anterior extremity of the body. The worm had two elliptical testes (anterior 0.47$\times$0.30 mm, posterior 0.59$\times$0.27 mm). The testes were close to the posterior end of the body. The uterus was very long, winding and extending through at least two thirds of the body length. The ovary (0.13$\times$0.14mm) was round and small. Below the ovary, a round and small seminal receptacle was found.

• Animal Systematics, Evolution and Diversity
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• v.28 no.1
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• pp.48-53
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• 2012

The tiger population that once inhabited the Korean peninsula was initially considered a unique subspecies (Panthera tigris coreensis), distinct from the Amur tiger of the Russian Far East (P. t. altaica). However, in the following decades, the population of P. t. coreensis was classified as P. t. altaica and hence forth the two populations have been considered the same subspecies. From an ecological point of view, the classification of the Korean tiger population as P. t. altaica is a plausible conclusion. Historically, there were no major dispersal barriers between the Korean peninsula and the habitat of Amur tigers in Far Eastern Russia and northeastern China that might prevent gene flow, especially for a large carnivore with long-distance dispersal abilities. However, there has yet to be a genetic study to confirm the subspecific status of the Korean tiger. Bone samples from four tigers originally caught in the Korean peninsula were collected from two museums in Japan and the United States. Eight mitochondrial gene fragments were sequenced and compared to previously published tiger subspecies' mtDNA sequences to assess the phylogenetic relationship of the Korean tiger. Three individuals shared an identical haplotype with the Amur tigers. One specimen grouped with Malayan tigers, perhaps due to misidentification or mislabeling of the sample. Our results support the conclusion that the Korean tiger should be classified as P. t. altaica, which has important implications for the conservation and reintroduction of Korean tigers.

• Journal of Korean Neurosurgical Society
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• v.63 no.2
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• pp.137-152
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• 2020

In spite of the developing endovascular era, large (15-25 mm) and giant (>25 mm) wide-neck cerebral aneurysms remained technically challenging. Intracranial flow-diverting stents (FDS) were developed to address these challenges by targeting aneurysm hemodynamics to promote aneurysm occlusion. In 2011, the first FDS approved for use in the United States market. Shortly thereafter, the Pipeline of Uncoilable or Failed Aneurysms (PUFS) study was published demonstrating high efficacy and a similar complication profile to other intracranial stents. The initial FDA instructions for use (IFU) limited its use to patients 22 years old or older with wide-necked large or giant aneurysms of the internal carotid artery (ICA) from the petrous segment to superior hypophyseal artery/ophthalmic segment. Expanded IFU was tested in the Prospective Study on Embolization of Intracranial Aneurysms with PipelineTM Embolization Device (PREMIER) trial. With further post-approval clinical data, the United States FDA expanded the IFU to include patients with small or medium, wide-necked saccular or fusiform aneurysms from the petrous ICA to the ICA terminus. However, IFU is more restrictive in South Korea than in United States. Several systematic reviews and meta-analyses have sought to evaluate the overall efficacy of FDS for the treatment of cerebral aneurysms and consistently identify FDS as an effective technique for the treatment of aneurysms broadly with complication rates similar to other traditional techniques. A growing body of literature has demonstrated high efficacy of FDS for small aneurysms; distal artery aneurysms; non-saccular aneurysms posterior circulation aneurysms and complication rates similar to traditional techniques. In the short interval since the Pipeline Embolization Device was first introduced, FDS has been firmly entrenched as a powerful tool in the endovascular armamentarium. As new FDS are developed, established FDS are refined, and delivery systems are improved the uses for FDS will only expand further. Researchers continue to work to optimize the mechanical characteristics of the FDS themselves, aiming to optimize deploy ability and efficacy. With expanded use for small to medium aneurysms and posterior circulation aneurysms, FDS technology is firmly entrenched as a powerful tool to treat challenging aneurysms, both primarily and as an adjunct to coil embolization. With the aforementioned advances, the ease of FDS deployment will improve and complication rates will be further minimized. This will only further establish FDS deployment as a key strategy in the treatment of cerebral aneurysms.

• Animal Systematics, Evolution and Diversity
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• v.21 no.1
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• pp.45-56
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• 2005

Three species of Gastrostyla ciliates collected from the sewage treatment plant and a puddle in the valley from Korea were identified as Gastrostyla minima Hemberger, 1985, G. steinii Engelmann, 1862 and G. setifera (Engelmann, 1862). The description was based on the observation of living specimens, protargol impregnated specimens and biometric analysis. The morphological variations among the populations of these species were investigated with morphometry. These species have not been reported in Korea and their diagnostic characteristics are as follows: G. minima normally has two oval macronuclei (Ma) with one spherical micronucleus (Mi) respectively, continuous ventral cirral row (VCR) with additional one postoral ventral cirrus (poVC), five transverse cirri (TC), six dorsal kineties (DK) with broken 4th kinety, and cortical granules. G. steinii has four oval Ma with three to five Mi, discontinuous VCR with additional one poVC, four TCs, six DKs, and no cortical granules. G. setifera has two oval Ma with one spherical Mi respectively, five TCs which distinctly separate in two groups, six DKs, discontinuous VCR with additional two poVCs, and no cortical granules.

• Animal Systematics, Evolution and Diversity
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• v.21 no.2
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• pp.233-241
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• 2005

Two new marine sponges of family Tedaniidae, Tedania (Tedon iu) songakensis n. sp. and Tedania (Tedonia) sasuensis n. sp. were collected from Jeju Island and Chuja Island, Korea between 2004 and 2005. T. (T.) songakensis n. sp. is similar to T (T.) purpurescen Bergquist and Fromont, 1988 based on its type of spicules, but is distinguished from growth form and size of small onychaetes. The growth form of this species is massive, and is compared with thin encrusting of Tedania (T.) purpurescen. The onychaetes of the new species is twice as long as that of T. (T.) purpurescen. T. (T.) sasuensis n. sp. is closely related to T. (T.) connectens (Bronsted, 1924) in type of spicules. However, it is different in size of onychaetes and growth form. The large onychaetes of new species is larger than that of T (T.) connectens. The small onychaetes of new species is smaller than that of T. (T.) connectens. The growth form is massive in new species, but thick encrustins in T.(T.) connectens. And T. (T.) songakensis n. sp. is similar to T. (T.) sasuensis n. sp. in growth form. However, the former is widely different from the latter in shape, color and size of all spicules.

• Animal Systematics, Evolution and Diversity
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• v.15 no.2
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• pp.153-164
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• 1999

One hundred and eleven samples of six subspecies of striped field mouse, Apodemus agrarius Pallas from Korea, China and Russia, were used for the analysis of mitochondrial DNA(mtDNA) fragment patterns resulted from the digestion with eight restriction enzymes by blot hybridization technique. All 32 fragments, nine mtDNA haplotypes, and four major subgroups with the mean divergence value of 0.896 to 1.150% were revealed. In summary, three forms are recognized: [I, subspecies chejuensis (Chejudo island, Korea)], [II, subspecies pallescens (southwestern Korea), coreae (central Korea), and septentrionalis (Russia)], and [III, subspecies manchuricus (northeastern China) and pallidior (northern China)], although some samples of subspecies coreae are somewhat different from almost all samples of six subspecies, and some samples of subspecies pallidior are similar with all samples of subspecies septentrionalis to form same haplotype. It is confirmed that A. agrarius chejuensis is a distinct subspecies, that subspecies coreae (including pallescens) is also a distinct subspecies, that subspecies manchuricus and pallidior are synonyms of subspecies ningpoensis, and that subspecies septentrionalis is a synonym of subspecies ningpoensis, and that subspecies septentrionalis is a synonym of subspecies agrarius. Moreover, it seems that A. agrarius shows constant karyotype, minimal variation in mtDNA genotype, and considerable divergence in morphometric characters, although further analyses with additional samples of A. agrarius in Eurasia will be necessary to determine the degree of variation of these taxonomic characters and to clarify subspecies classification as well.

• Animal Systematics, Evolution and Diversity
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• v.15 no.2
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• pp.165-174
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• 1999

Specimens of five species of Apodemus(A. agrarius, A. chevrieri, A. draco, A. latronum, and A. peninsulae) from east Asia (Korea and China) were used for numerical taxonomic analyses with 31 external and cranial characters. Two groups and eight subgroups within them were recognized: [I; a large-size form; (A. agrarius chejuensis), (A. chevrieri), (A. draco orestes and A. latronum), and(A. peninsulae peninsulae and A. p. preator)], [II; a small-size form; (A. agrarius coreae), (A. agrarius manchuricus, A. a. ningpoensis, and A. a. pallidior), (A. draco draco), and (A. peninsulae sowerbyi)]. Conclusions based on morphometric analyses are such as followings: 1) Morphometric characters appeared not to be useful in order to distinguish two subgenera in Apodemus (Apodemus and Alsomys), 2) further analysis is necessary to determine whether or not A. draco and A. latronum are conspecific, and 3) A. a. chejuensis is in morphometric characters the largest form among five species of Apodemus studied. Moreover, it is confirmed: 1) A. agrarius, A. chevrieri, and A. peninsulae are distinct species, 2) A. draco and A. latronum are not conspecific with A. peninsulae. 3) Three forms of A. agrarius (large-size form, medium-size form, and small-size form) can be recognized as three subspecies [(A. a. chejuensis), (A. agrarius coreae), and (A, a, ningpoensis including A. a. manchuricus and A. a. pallidior)], 4)A. draco draco and A. draco orestes are distinct subspecies, 5) A. peninsulae peninsulae (including A. p. preator) and A. p. sowerbyi are distinct subspecies.