• Korean journal of applied entomology
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• v.56 no.2
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• pp.107-120
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• 2017

Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species composing the B. tabaci complex were determined based on 550 COI gene sequences of B. tabaci. Genetic divergence within B. tabaci ranged from 0% to 27.8% (average 11.1%). This result indicates that the B. tabaci complex is composed of multiple species that may belong to different genera or subfamilies. A phylogenetic tree constructed based on 217 COI gene sequences without duplications revealed that the B. tabaci complex is composed of a total of 43 putative species, including a new species, Java. In addition, genetic divergence within nine species (Australia, Asia II 1, Asia II 6, Asia II 7, Asia II 10, Mediterranean, New world, New world 2, Sub Saharan Africa 1) indicates that 4.0% is reasonable to be used as a threshold of species boundaries within the B. tabaci complex, and species with high intraspecific genetic divergences can be related with cryptic species.

• Animal Systematics, Evolution and Diversity
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• v.28 no.4
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• pp.269-278
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• 2012

Gobiids are hyperdiverse compared with other teleost groups, with about 2,000 species occurring in marine, freshwater, and blackish habitats, and they show a remarkable variety of morphologies and ecology. Testing the effectiveness of DNA barcodes on species that have emerged as a result of radiation remains a major challenge in evolutionary biology. Here, we used the cytochrome c oxidase subunit 1 (COI) sequences from 144 species of gobies and related species to evaluate the performance of distance-based DNA barcoding and to conduct a phylogenetic analysis. The average intra-genus genetic distance was considerably higher than that obtained in previous studies. Additionally, the interspecific divergence at higher taxonomic levels was not significantly different from that at the intragenus level, suggesting that congeneric gobies possess substantial interspecific sequence divergence in their COI gene. However, levels of intragenus divergence varied greatly among genera, and we do not provide sufficient evidence for using COI for cryptic species delimitation. Significantly more nucleotide changes were observed at the third codon position than that at the first and the second codons, revealing that extensive variation in COI reflects synonymous changes and little protein level variation. Despite clear signatures in several genera, the COI sequences did resolve genealogical relationships in the phylogenetic analysis well. Our results support the validity of COI barcoding for gobiid species identification, but the utilization of more gene regions will assist to offer a more robust gobiid species phylogeny.

• Animal cells and systems
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• v.16 no.2
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• pp.145-153
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• 2012

The pear psylla, $Cacopsylla$ $pyricola$ (Hemiptera: Psyllidae), is a serious insect pest of commercial pear crops. The species, which resides on pear trees throughout its life cycle, is rapidly spreading in some regions of the world. The population genetic structure of the species collected from several pear orchards in Korea was studied to understand the nature of dispersal and field ecology of the species. The 658-bp region of mitochondrial COI gene and the 716-bp long complete internal transcribed spacer 2 (ITS2) of the nuclear ribosomal DNA were sequenced. Unlike other previously studied insect pests, the COI-based genetic diversity of the pear psylla was extremely low (maximum sequence divergence of 0.15%). This finding allowed us to conclude that the species may have been introduced in Korea relatively recently. ITS2 sequence-based analyses of phylogeny, population differentiation, gene flow, and hierarchical population structure all concordantly suggested that the pear psylla populations in Korea are neither genetically isolated nor hampered for gene flow. These genetic data are concordant with the dispersal of an overwintering winterform morph outside the non-pear habitat in the fall.

• Animal Systematics, Evolution and Diversity
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• v.31 no.4
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• pp.311-315
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• 2015

Euryalid specimens were collected from Gonghyeonjin and Daejin, Gangwon-do in the East Sea, Korea at a depth of 250-300 m by fishing nets on November 2013 and August 2014. They were identified as Gorgonocephalus arcticus Leach, 1819 belonging to family Gorgonocephalidae of order Euryalida, which was new to the Korean fauna. Nucleotide sequences of partial mitochondrial cytochrome c oxidase I (mt-COI) gene, which was 569 bp in length, were compared among four Gorgonocephalus species, and were subsequently employed to reconstruct phylogenetic trees using the MP, ML, and BI methods. As a result, no sequence difference was found between the G. arcticus mt-COI gene sequences from Korea and Canada, and the two made a strong monophyletic group. With the newly recorded G. arcticus in Korea, in total, four Gorgonocephalus species have been reported in Korea.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.63-68
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• 2003

We investigated the sequence divergence of the geographic samples of the queen bumble bee (Bombus ardens) in Korea. A portion of mitochondrial COI gene sequences (423 bp) was analyzed for 44 individuals collected from seven localities. Sequence analysis resulted in four COI haplotypes with the maximum nucleotide divergence of only 0.5% (two bp). One haplotype (BA1) was dominant in all localities surveyed (86.4%). The finding of low sequence divergence and dominance of one haplotype appear to reflect, although limited, the life history of the B. ardens queens subjected to active dispersal and seasonal fluctuation in queen number.

• Korean Journal of Ichthyology
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• v.21 no.4
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• pp.287-290
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• 2009

A natural hybrid between the striped spine loach Cobitis tetralineata and the king spine loach Iksookimia longicorpa was genetically identified by sequence analyses of nuclear recombination activating gene 1 (RAG1) and mitochondrial cytochrome c oxidase I (COI) genes. Out of 850 base positions of RAG1, a total of 23 nucleotide substitutions were detected between the two parental species, whereas the electropherogram of the natural hybrid displayed double peaks at all of the 23 positions, which reflects their simple Mendelian inheritance pattern. Meanwhile, comparison of partial sequences of mitochondrial genes (COI in this study), which are well characterized by the maternal inheritance pattern, revealed that the maternal species of the hybrid was C. tetralineata because of their 100% sequence identity.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.377-377
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• 2003

We investigated the biogeography of Asian Corbicula using mitochondrial gene sequence variation for Corbicula members sampled from 24 localities of 8 Asian regions. A total of 210 individuals were genetically characterized by examining sequence variations of a 614 bp fragment of the mitochondrial cytochrome oxidase I (COI) gene. Phylogenetic analyses of the COI dataset revealed that Corbicula members are subdivided into two well-supported clades: estuarine and freshwater. (omitted)

• Fisheries and Aquatic Sciences
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• v.24 no.5
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• pp.181-190
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• 2021

Grouper is one of the most economically important fishes with various morphological forms and characteristics, meaning it is often difficult to identify species and distinguish between life stages, sometimes leading to morphological misidentification. Therefore, identification using a molecular deoxyribose nucleic acid (DNA) approach was needed as an alternative means to identify closely related species. This study aims to determine the molecular phylogeny of grouper from the northern part of the Bird's Head Seascape of Papua. The DNA sequence of each cytochrome oxidase I (COI) gene was used to study the molecular relationship among closely related species of grouper. The results showed that there were 16 Epinephelinae that have been compared to a gene bank (National Centre for Biotechnology Information, NCBI) in the sequence length of 623 base pairs. The closest genetic distance was found between Cephalopholis miniata and Cephalopholis sexmaculata (0.036), while the furthest genetic distance was observed between Plectropomus laevis and Cephalopholis spiloparaea (0.247). This finding was further reinforced by the morphological characters of each species. This finding highlighted that five genera were represented as a monophyletic group (clade), i.e., Epinephelus, Cephalopholis, Plectropomus, Saloptia and Variola.

• Animal Systematics, Evolution and Diversity
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• v.23 no.1
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• pp.75-85
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• 2007

A taxonomic study was carried out on the Perinereis nuntia species group of Korea by using morphological and molecular data (mitochondrial cytochrome c oxidase subunit I: mtCOI). Two species, P. mictodonta (Marenzeller, 1879) and P. wilsoni (Glasby and Hsieh, 2006), are recognized and redescribed. In this study, mtCOI gene showed a good resolution as molecular marker for species identification of the P. nuntia species group of Korea.

• Fisheries and Aquatic Sciences
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• v.9 no.3
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• pp.101-106
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• 2006

The cytochrome c oxidase subunit I (COI) gene region of mitochondrial DNA (mtDNA) was examined in four abalone species to estimate its utility as a genetic marker using restriction fragment length polymorphism (RFLP) analysis. The utility was evaluated in terms of genetic divergence and relationships among Haliotis discus hannai, H. rufescens, H. rubra, and H. midae in both hemispheres of the world. There was clear genetic divergence in the mtDNA COI region between all pairs of the four species. Moreover, relationships among the abalone species were reflected in their geographical distributions and morphological characteristics. Therefore, RFLP analysis of the mtDNA COI region is a suitable genetic marker for the estimation of genetic divergence and relationships among abalone species. However, it is not effective for the evaluation of genetic differences within abalone species.