• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.1
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• pp.62-64
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• 2003

Recently, relatively large amount of a new species of crab belonging to genus Chionoecetes that has intermediate characteristics between red-tanner crab (Chionoecetes japonicus) and queen crab (C. opilio) was caught the East Sea of Korea. The new species of crab was tentatively named Neodo-Daege. Amino acid and proximate compositions of the edible meat of red-tanner crab and Neodo-Daege were determine. The proximate composition of the meats of Neodo-Daege were $79.2{\%}$ in moisture, $17.4{\%}$ in protein, $0.6{\%}$ in lipid, and $1.5{\%}$ in ash. Neodo-Daege was higher in protein and lipid contents, and lower in moisture and ash contents than those of red-tanner crab. The total amino acid contents in the meat of Neodo-Daege were higher than those of red-tanner crab, but the profile of amino acids was similar to one another. Among amino acids, glutamic acid, arginine, aspartic acid, lysine and glycine were major components of the crabs.

• ALGAE
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• v.33 no.2
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• pp.143-156
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• 2018

Dolichospermum is a filamentous and heterocytous cyanobacterium that is one of the commonly occurring phytoplanktons in the Han River of Korea. Morphological observations led to the identification of D. planctonicum-like filaments in seasonal water samples. In the present study, we successfully isolated these filaments using culture methods, and examined its morphology using light and scanning electron microscopy. The morphology of the D. planctonicumlike species differed from that of typical D. planctonicum; it had thin cylindrical-shaped akinetes, which were narrower towards the ends than at the center. This morphology is firstly described in the genus Dolichospermum. In addition, the akinetes in the filament developed solitarily and were distant from the heterocytes. Phylogenetic analysis of the 16S rRNA sequences showed that our Dolichospermum clustered with D. planctonicum and D. circinale, which have coiled trichome. However, phylogenetic analysis of the gene encoding rivulose-1,5-bisphosphate carboxylase (rbcLX) clearly separated our species from other Dolichospermum, forming a unique clade. Additionally, structures of D. planctonicum and D. hangangense strains were different type in Box-B and V3 region. These results demonstrated that the new Dolichospermum species was unique in morphology and molecular traits. Therefore, we propose this to be a new species belonging to genus Dolichospermum with the name Dolichospermum hangangense sp. nov.

• ALGAE
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• v.35 no.4
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• pp.303-324
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• 2020

Cocconeis coreana and C. sijunghoensis are described as new based on micromorphological and molecular data. C. coreana is represented by five unialgal cultures from four different freshwater bodies, two from North Korea and three from South Korea. C. sijunghoensis is represented by two unialgal cultures from a brackish water body in North Korea. Except for one, all of the strains auxosporulated and showed an almost quadrupling of size in length and width. Morphologically, these species with their two different elliptical valves belong to the Cocconeis placentula group. The raphe valve has striae with uniseriate areolae continuing across a pronounced submarginal hyaline rim to the edge of the valve. The sternum valve has uniseriate dash-like areolae continuously from the valve face until the valve edge. Micromorphologically, these species possess two different open valvocopulae: only the raphe valvocopula has fimbriae; the sternum valvocopula has none. Based on p-distances of currently available DNA sequence data, i.e., rbcL and 18SV4, both species are pronouncedly different from the epitype strain of C. placentula, with C. coreana closest to the published molecular data of the strain UTEX FD23 named C. placentula from Iowa, USA, while C. sijunghoensis is closest but not the same as the published molecular data of strain D36_012, the epitype strain of C. placentula from Berlin, Germany. Based on scanning electron microscope observations, differentiating features are discussed concerning valvocopula fimbriae, central area, areolation of the sternum valve and on the raphe valve especially between the submarginal hyaline rim and edge.

• Korean Journal of Plant Tissue Culture
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• v.22 no.5
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• pp.241-260
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• 1995

Transposons, present in the genomes of all living organisms, are genetic element that can change positions, or transpose, within the genome. Most genomes contain several kinds of transposable elements and the molecular details of the mechanisms by which these transposons move have recently been uncovered in many families of transposable elements. Transposition is brought about by an enzyme known as transposaese encoded by the autonomous transposon itself, but, in the unautonomous transposon lacking the gene encoding the transposase, movement occurs only at the presence of the enzyme encoded by the autonomous one. There are two types of transposition events, conservative and replicative transposition. In the former the transposon moves without replication, both strands of the DNA moving together from one place to the other while in the latter the transposition frequently involves DNA replication, so one copy of transposon remains at its original site as another copy insole to a new site. The insertion of transposon into a gene can prevent it expression whereas excision from the gene may restore the ability of the gene to be expressed. There are marked similarities between transposons and certain viruses having single stranded Plus (+) RNA genomes. Retrotransposons, which differ from the ordinary transposons in that they transpose via an RNA-intermediate, behave much like retroviruses and have a structure of integrated retrovial DNA when they are inserted to a new target site. An insertional mutagenesis called transposon-tagging is now being used in a number of plant species to isolate genes involved in developmental and metabolic processes which have been proven difficult to approach by the traditional methods. Attempts to device a transposon-tagging system based on the maize Ac for use in heterologous species have been made by many research workers.

• Korean Journal of Plant Taxonomy
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• v.45 no.3
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• pp.262-265
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• 2015

Two species of Syrrhopodon [S. japonicus (Besch.) Broth. and S. armatus Mitt.] were newly recorded from Jeju Island. S. japonicus was found on a rock covered with fine soil on the Che-oreum Volcano. This species is clearly distinguished from other species of the genus by its plants to 40 mm long, leaves bordered with several rows of short cells, and the margins at the leaf shoulders being regularly serrate. Syrrhopodon armatus was found on tree bark on Seopseom islet. It differs morphologically from other species of the genus in terms of its plant at 10 mm long, leaves bordered with one to several rows of linear and hyaline cells, leaves with spinous teeth at the shoulders. We propose new Korean names for these two species: 'Seon-o-reum-i-kki' and 'Jag-eun-seon-o-reum-i-kki,' respectively, which are based on their plant size and their first locations in Korea.

• Korean Journal of Plant Taxonomy
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• v.41 no.3
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• pp.235-241
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• 2011

Five unrecorded species (Oedipodium griffithianum, Myurella tenerrima, Trachypus bicolor, Coscinodon humilis, Meteorium miquelianum subsp. atrovariegatum) with one unrecorded family and two unrecorded genera, were reported as new to the Korean moss flora. The monotypic family Oedipodiaceae consisting of a single genus and single species was distinguished from Splachnaceae by small plants that were 10 mm in length simple or sometimes branched, obovate-spathulate to ${\pm}$ orbicular, costa ending below the apex and entire margins except for the lower long-ciliate portion The species was first found at the top of the Mt. Seorak at an altitude of 1708 m. The two genera, Myurella and Coscinodon were found in the Korean Peninsula. Myurella tenerrima (Theliaceae) was found around the top of Jung-bong on Mt. Jiri. It was mixed with other mosses in the crevices of rocks in the alpine regions. The species is similar to M. sibirica, yet it can be distinguished by the position of papilla in the median laminal cells. Coscinodon humilis (Grimmiaceae) were found on the ridge of Mt. Gaya. C. humilis has a variety of hyaline apex according to leaf position and forms a capsule so it can be distinguished by family. Trachypus bicolor and Meteorium miquelianum subsp. atrovariegatum are unrecorded species. T. bicolor (Trachypodaceae) were found on the ridge of Mt. Gaya. T. bicolor is similar to T. humilis but distinguished by the costal lengths of the leaves. M. miquelianum subsp. atrovariegatum (Meteoriaceae) was found in Gageo-do. This species was distinguished by the plant form and morphology of stem leaves in the same genus.

• Animal cells and systems
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• v.6 no.1
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• pp.45-51
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• 2002

We compared the complete mitochondrial cytochrome b gene sequences of Korean and European cobitids to provide independent evidence for assessment of systematic and biogeographic relationships of species in the genus Cobitis. The data suggested monophyly of the genus Cobitis and the inclusion of Korean Cobitis species within the group having one lamina circularis, a primitive condition. Also, all the phylogenetic analyses using maximum parsimony, maximum likelihood, and neighbor joining methods showed a monophyletic relationship among Cobitis. The basal position of the Caspian C. cf. sibirica reported here reflects the eastern Asiatic origin cf. the European Cobitis and establishes C. cf. sibirica as an independent lineage. The Korean C. pacifica diverged next to C. cf. sibirica in basal group from the genus Cobitis. This result is in agreement with the hypothesized Asiatic origin of some European freshwater fish lineages. The phylogenetic relationships in this study showed a close affinity between C. zanadreai and C. sinensis. Two new species, C. tetralineata and C. pacifica in Korea also are closely related to monophyletic group clustering the type species of the Acanestrinia subgenus (C. elongata) with all the endemic Italian species (C. bilineata and C. zanandreai). This may suggest that the affinity between the Korean and Danubian-Italian imply genetic convergence or genetic plesiomorphic state between allopatric species that are separated for the Miocene. The mtDNA-based phylogeny for the species of the genus Cobitis from Kores and Europe permits phylogenetic assessment of the morphological transitions of Iamina circularis.

• Animal Systematics, Evolution and Diversity
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• v.17 no.2
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• pp.165-169
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• 2001

We describe tubular structures on the cuticle of two representatives of the genus Gordius by scanning electron microscopy. One female from Korea could not be identified further while a male from New Zealand belonged to Gordius paranensis. Other male specimens of G. paranensis did not show tubular structures or the corresponding pores on the cuticle. Therefore it is assumed that tubular structures are not species-specific structures, but also no artifacts or contaminations. They might be glandular products, but this has to be verified by further documentations and investigation of the inner structure of it.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.1
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• pp.248-257
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• 2016

The international collaboration on marine biodiversity increases in the proportion of the world's scientific papers produced with more than one international author, 2006-2010. The number of scientific papers from 2006 to 2010 describing "marine new species (or spec. nov., n. sp.)" published 401 (international ranking : $13^{th}$) by S. Korea, 824 ($7^{th}$) by China, 1,249($5^{th}$) by Japan, 1,282($3^{rd}$) by Austrailia, and 3,679 ($1^{st}$) by United States. The papers having an international co-authorship account for 52.0% by S. Korea, 79.0% by China, 67.0% by Japan, 81.0% by Australia at the same period. The proportion of national publication output produced in collaboration with other countries differs proportionately between countries. In S. Korea, the overall numbers of international collaboration were not growing significantly. Both in Japan and China, an overall numbers of international collaboration increased well in accordance with the proportion of national output with international collaboration.

• Animal Systematics, Evolution and Diversity
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• v.11 no.4
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• pp.509-538
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• 1995

Twenty-one speices of the terrestrial isopods are recorded from Cheju Island and Chja Island, Korea. Quepartoniscus tuberculatus, n. gen., n.sp., is described. The genus Koshiniscus Nunomura is considered to be a junior synonym of Armadilloniscus Uljanin, Armadilloniscus hoshikawai Nunomura and A. amakusaensis Nunomura of A. ellipticus, Mongloiscus nipponicus (Arcangeli) of M. vannamei(Arcangeli), Nagurus tsushimaensis Nunomura, N. pallidus Nunomura, and Mongoloniscus nigrogranulatus Kwon and Tatiti of M. koreanus (Verhoeff). Nagurus sinuosus Nunomura is transferred to Lucasioides Kwon , Protracheoniscus pannuosus Nunomura (of which P.awaensis Nunomura, Nagurus gotoensis Nunomura, and N. izuharaensis Nunomura are synonyms ) to Agnara Budde-Lund, and Armadillo obscurus Budde-Lind to Venezillo Verhoeff. Several poorly known species are redescribed and illustrated.