• Animal Systematics, Evolution and Diversity
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• v.18 no.1
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• pp.1-12
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• 2002

Actaea semblatae (Guinot, 1976) has been roared in the laboratory, from hatching to the first young crab stage at $25^{\circ}C$. The two zoeal stages are described and illustrated in detail. The first zoea of A. semblatae in the present study slightly differs from that described by Terada (1987) on the respect of the setal presence on the carapace, the antennule, the coxa of the first maxilliped and the first abdominal somite. Within the family Xanthidae, the zoea of A. semblatae can be clearly distingushed from the other known zoeas by having a seta as an antennal exopod or a vestigial exopod with a sets. A provisional key is provided to aid the identification of the xanthid zoeas in Korea.

• Animal Systematics, Evolution and Diversity
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• v.27 no.1
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• pp.1-17
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• 2011

Thais Roding, 1798, commonly known as rock-shell, is among the most frequently found gastropod genera worldwide on intertidal rocky shores including those of Japan, China, Taiwan and Korea. This group contains important species in many marine environmental studies but species-level taxonomy of the group is quite complicated due to the morphological variations in shell characters. This study examined the genetic variations and relationships among three Korean Thais species based on the partial nucleotide sequences of mitochondrial cox1 gene fragments. Phylogenetic trees from different analytic methods (maximum parsimony, neighbor-joining, and maximum likelihood) showed that T. bronni and T. luteostoma are closely related, indicating the most recent common ancestry. The low sequence divergence found between T. luteostoma and T. bronni, ranging from 1.53% to 3.19%, also corroborates this idea. Further molecular survey using different molecular marker is required to fully understand a detailed picture of the origin for their low level of interspecific sequence divergence. Sequence comparisons among conspecific individuals revealed extensive sequence variations within the three species with maximum values of 2.43% in T. clavigera and 1.37% in both T. bronni and T. luteostoma. In addition, there is an unexpectedly high level of mitochondrial genotypic diversity within each of the three Korean Thais species. The high genetic diversity revealed in Korean Thais species is likely to reflect genetic diversity introduced from potential source populations with diverse geographic origins, such as Taiwan, Hong Kong, and a variety of different coastal regions in South China and Japan. Additional sequence analysis with comprehensive taxon sampling from unstudied potential source populations will be also needed to address the origin and key factors for the high level of genetic diversity discovered within the three Korean Thais species studied.

• Animal Systematics, Evolution and Diversity
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• v.7 no.2
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• pp.179-188
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• 1991

In order to determine the taxonomic status of Apodemus agrarius chejuensis from Cheju island in Korea, three hundred and eleven samples of eight subspecies of striped field mice (subspecies, agrarius, ningpoensis , pallidior, chevrieri, insulaemus, manchuricus, coreae, and chejuensis of A. agrarius Pallas) in Asia, collected from Turkey , China, Taiwan, , Manchuria, and Koarea, were used. Four external and 27 cranial characters were measured and their measurements were utilized for multivariate analyses such as cluster, principal component, and discriminant analyses. Four forms were revealed . A largest-size from was chejuensis, whereas a large-size form was cheverieri. A medium -size from and a small-size from were coreae and other five subspecies (agrarius , ningpoensis, pallidior, insulaemus, and manchuricus) , respecitvley, but their differences were clinal. A discontinuous gap was revealed between chejuensis (a largest-size from) and six subspecies ( a medium-size from and a small-size form) Although chejuensis appeared to be a distinct species, it is concluded that molecular analyses are necessary in order to describe it as a new species.

• Korean Journal of Plant Resources
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• v.25 no.2
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• pp.257-270
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• 2012

The taxonomic relationship of 3 taxa in $Carex$ sect. $Siderostictae$ were revealed by morphological and molecular studies. The morphological characteristics of Korean $Carex$ siderosticta Hance, which is a type species of sect. $Siderostictae$, was first reviewed in comparison with previous records in order to identify the difference. Then the distribution map of this species was formulated through previous floral literatures and voucher specimens. Although the leaf shape which is represented by length/width ratio showed a great variation depending on habitat condition, the rhizome creeping patterns, the presence of hair on the surface leaf margin and perigynium were shown to be good diagnostic characters to define delimitation of species level. The results from molecular study supported $C.$ $ciliatomarginata$ Nakai should be ranked independently on species level.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.38.2-38.2
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• 2016

The mapping of dark matter clustering from real to redshift spaces introduces the anisotropic property to the measured density power spectrum in redshift space, known as the Redshift Space Distortion (hereafter RSD) effect. The mapping formula is intrinsically non-linear, which is complicated by the higher order polynomials due to the indefinite cross correlations between the density and velocity fields, and the Finger-of-God (hereafter FoG) effect due to the randomness of the peculiar velocity field. Furthermore, the rigorous test of this mapping formula is contaminated by the unknown non-linearity of the density and velocity fields, including their auto- and cross-correlations, for calculating which our theoretical calculation breaks down beyond some scales. Whilst the full higher order polynomials remains unknown, the other systematics can be controlled consistently within the same order truncation in the expansion of the mapping formula, as shown in this paper. The systematic due to the unknown non-linear density and velocity fields is removed by separately measuring all terms in the expansion using simulations. The uncertainty caused by the velocity randomness is controlled by splitting the FoG term into two pieces, 1) the non-local FoG term being independent of the separation vector between two different points, and 2) the local FoG term appearing as an indefinite polynomials which is expanded in the same order as all other perturbative polynomials. Using 100 realizations of simulations, we find that the best fitted non-local FoG function is Gaussian, with only one scale-independent free parameter, and that our new mapping formulation accurately reproduces the observed power spectrum in redshift space at the smallest scales by far, up to k ~ 0.3 h/Mpc, considering the resolution of future experiments.

• Animal Systematics, Evolution and Diversity
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• v.38 no.4
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• pp.226-237
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• 2022

Arcuospathidium is a haptorian ciliate genus composed of 18 species, and only one species has been reported in Korea. Here, we identify two unrecorded Arcuospathidium subspecies by morphological observation of both living and protargol-impregnated specimens with the small subunit ribosomal RNA (18S rRNA) gene sequence. These subspecies, Arcuospathidium cultriforme cultriforme (Penard, 1922) Foissner, 1984 and A. cultriforme scalpriforme (Kahl, 1930) Foissner, 2003, were isolated from various terrestrial habitats in July and August 2013, respectivley. Arcuospathidium cultriforme cultriforme is similar to A. cultriforme scalpriforme by a knife-shaped body, a twisted-shaped macronucleus, number of dorsal brushes, position of dorsal brushes, and shape of macronucleus but former mainly differs from the body length to oral bulge length ratio (27-38% vs. 41-53%), extrusome (one types vs. three types), cyst shape (roughly faceted wall vs. smooth surface and thin wall) and number of somatic kinety rows(18-30 vs. 30-44). Additionally, we analyzed the 18S rRNA gene sequences of two A. cultriforme subspecies and compared them with the sequences from GenBank to confirm their identification at the molecular level. As the results of genetic analysis, the 18S rRNA gene sequence of the Korean A. cultriforme cultriforme population is most similar to that of Austrian population. Also, the sequence of the Korean A. cultriforme scalpriforme population is most similar to that of another population with some nucleotide differences.

• Korean Journal of Environment and Ecology
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• v.11 no.3
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• pp.277-289
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• 1997

Electrophresis methods were used to examined the degree of genetic relatedness and divergent times on the 4 genera 4 species of the family Corvidae and 1 species of the Family Cinclidae. Genetic relatedness between two families and between 4 genera of Corvidae showed similar to those reported at comparable taxonomic levels in other bird. But it appears to be considerably less than that of non avian taxa. Genetic relatedness between Garrulus glandarius brandtii and Corvus corone orientalis was the most close related(S=0.81), whereas Pica pica sericea(S=0.72) and Cyanopica cyanus koreensis(S=0.68) were showed less close relatedness respectively. The presumed divergent time between two families was 3.9 million years before present. Whereas among the 4 species of corvidae, the presumes divergent times of Cyanopica cyanus koreensis and Pica pica sericea were about 1.9 and 1.6 million years before present respectively, and between Garrulus glandarius brandtii and Corvus corone orientalis was showed recently about 1.0 million years before present

• Parasites, Hosts and Diseases
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• v.55 no.1
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• pp.39-45
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• 2017

The present study was performed to reveal the morphological characteristics and molecular phylogenetic position of Platynosomum fastosum Kossack, 1910. A total 167 specimens of P. fastosum were collected in 8 (4.9%) out of 163 sets of gall-bladders and bile ducts of cats. The number of worms was 1-105 per infected cat. This species was characterized by having a long and slender body, slightly larger ventral sucker than the oral sucker, indistinct prepharynx, small pharynx, short esophagus, bifurcation midway between 2 suckers, and ceca extending to the posterior end of the body. The length of the partial sequences of ITS1 and 5.8S rDNA of P. fastosum were 990 bp, GC-rich. AT/GC ratio was 0.9, there were 9 polymorphic sites, and intraspecific variations ranged from 0.1% to 0.9%. Phylogenetic analyses by neighbor-joining phylogram inferred from ITS1 rDNA sequences revealed that the genetic distance between P. fastosum specimens ranged from 0.3 to 1.5% while the smallest interspecific distance among dicrocoeliid species was 20.9 %. The redescription and genetic characters of P. fastosum are taxonomically important to recognize future different species of the genus Platynosomum showing high intraspecific and morphological variability.

• Animal Systematics, Evolution and Diversity
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• v.13 no.3
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• pp.233-246
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• 1997

A genetic analysis using starch gel electrophoresis was performed to clarify the degrees of genetic differentiation and the phylogenetic relationships among four species of the genus Corbicula (Bivalvia, Corbiculidae). The average genetic similarity coefficients among the populations of each species on C. fluminea, C. leana and C. colorata were very closed (Rogers' S$\geq$0.970), whereas the other C. japonica was separated into two genetic groups (S=0.873) with distinct allelic difference at the Gpl locus. Thuefore additional taxonomic studies are needed on this species. On the other hand, these four species were well distinguished from each other genetically with distinct allelic differences at 4 to 9 loci. The genetic similarity coefficients (S) between C. leana and C. colorata, C. fluminea and C. leana, and C. fluminea and C. colorata were 0.737, 0.689, and 0.594, respectively. In particular, the average genetic similarity coefficients between these three species (inhabiting in freshwater) and the other C. japonica (inhabiting in brackishwater) were notably lower (S=0.370).

• Korean Journal of Plant Resources
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• v.9 no.3
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• pp.298-304
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• 1996

The fruit wall anatomy of Ocotea was investigated on the basis of 14 species within the genus to contribute to a better understanding of specific relationships and homogeneity of genus. The species have a similar mature fruit wall structure, but diUerences among the species are found with respect to whether or not sdc.nchyma cells are present in the mesocarp. if present, whether or not they are present in particular positions and forms. Comparisons with species studied suggested that at least a few groups of species can be distinguished in Ocotea. They arc divided into five groups on the basis of anatomical structures. i.e., group 1) O. atrriensis, O. cujumari, O. helicterifolia, O. rubra and O. schomburgkiana; group 2) O. aeiphylla, O. javitensis, and O. sp. [Werff et ai. 12676]; group 3) O. tonduzii: group 4) O. foetens, O. quixos, and O. veraguensis; and group 5) O. floribunda and O. nitida. These various variations in Ocntea were also discussed to invite its respective systematic revisions. By the comparisons with species, on the other hand, it suggested that the specialized species are evolved from non-specialized species.