• Animal Systematics, Evolution and Diversity
• /
• v.37 no.3
• /
• pp.219-224
• /
• 2021

A hesionid species, Leocratides kimuraorum Jimi, Tanaka and Kajihara, 2017 is newly reported from the sublittoral zones (100 m depth) of the Korean coasts. This species is characterized by lateral antennae as long as the palps, peristomial membrane without papillose, peristomial dorsolateral tubercles with two round marginal lobes, and pharyngeal with terminal papillae. The intra-specific genetic distance among the cytochrome c oxidase subunit I(COI) sequences of L. kimuraorum specimens from Japan (type locality) and Korea (this study) was in the range of 0.002-0.005. The inter-specific genetic distance between L. kimuraorum and other hesionid species were 0.166-0.307. The present study is the first record of Leocratides species in Korean fauna. This paper also provides a morphological description and photographs of L. kimuraorum, with partial sequences of the mitochondrial COI based on Korean specimens.

• Journal of information and communication convergence engineering
• /
• v.21 no.2
• /
• pp.159-166
• /
• 2023

The COI gene is a sequence of approximately 650 bp at the 5' terminal of the mitochondrial Cytochrome c Oxidase subunit I (COI) gene. As an effective DeoxyriboNucleic Acid (DNA) barcode, it is widely used for the taxonomic identification and evolutionary analysis of species. We created a CNN-LSTM hybrid model by combining the gene features partially extracted by the Long Short-Term Memory ( LSTM ) network with the feature maps obtained by the CNN. Compared to K-Means Clustering, Support Vector Machines (SVM), and a single CNN classification model, after training 278 samples in a training set that included 15 genera from two orders, the CNN-LSTM hybrid model achieved 94% accuracy in the test set, which contained 118 samples. We augmented the training set samples and four genera into four orders, and the classification accuracy of the test set reached 100%. This study also proposes calculating the cosine similarity between the training and test sets to initially assess the reliability of the predicted results and discover new species.

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

• Ocean and Polar Research
• /
• v.42 no.3
• /
• pp.263-270
• /
• 2020

The distribution and genotypes of the sea nettle Chrysaora pacifica have been reported in the South Sea of Korea; however, little research work has been attempted in the East Sea. Here, we collected similar jellyfishes from the East Sea coasts (Goseong, Yangyang and Sokcho), and identified them to the sea nettle morphologically. In addition, the genotypes of these sea nettle were compared with those from the South Sea (Tongyeong and Geoje). Phylogenetic analysis by using the mitochondrial COI sequences showed that the genus Chrysaora was clearly separated from other taxa to be formed a monophyletic group, with each species distinctly separated. C. pacifica in the East and South Seas was separated geographically by the COI phylogeography, representing potentially different populations. The COI gene of the Korean C. pacifica had approximately 7 times more genetic variation than the nuclear ITS rDNA, and thus it might be considered as a useful marker for genetic analysis of the jellyfish population.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.7 no.2
• /
• pp.181-189
• /
• 2003

We describe here the complete nucleotide sequence and the exon-intron structure of the luciferase gene of the firefly, Pyrocoelia rufa. The luciferase gene of the P. rufa firefly consisted of six introns and seven exons coding for 548 amino acid residues. From the translational start site to the end of last exon, however, the genomic DNA length of the P. rufa luciferase gene from the Korean and Chinese samples spans 1,968 bp and 1983 bp, respectively, and 3 amino acid residues were different to each other. Additionally, we also analyzed mitochondrial cytochrome oxidase I(COI) gene of the Chinese P. rufa fireflies. Analysis of DNA sequences from the mitochondrial COI protein-coding gene revealed 4 mitochondrial DNA sequence-based haplotypes with a maximum divergence of 0.7％. With the 20 P. rufa haplotypes found in Korea, phylogenetic analyses using PAUP and PHYLIP subdivided the P. rufa into three clades, termed clades A and B for the Korean sample, and clade C for the Chinese sample.

• Fisheries and Aquatic Sciences
• /
• v.25 no.12
• /
• pp.601-618
• /
• 2022

The genus Semisulcospira is an economically and ecologically valuable freshwater resource. Among the species, Semisulcospira coreana, Semisulcospira forticosta and Semisulcospira tegulata are endemic to the Korean peninsula and Semisulcospira gottschei is widespread in Asia. Therefore, maintenance and conservation of wild populations of these snails are important. We investigated the genetic diversity and population structure of Semisulcospira based on the mitochondrial cytochrome c oxidase subunit I (COI), NADH dehydrogenase subunit 4 (ND4), and combined mitochondrial DNA (COI + ND4) sequences. All four species and various genetic makers showed a high level of haplotype diversity and a low level of nucleotide diversity. In addition, Fu's Fs and Tajima's D neutrality tests were performed to assess the variation in size among populations. Neutrality tests of the four species yielded negative Fu's Fs and Tajima's D values, except for populations with one haplotype. The minimum spanning network indicated a common haplotype for populations of S. coreana, S. tegulata and S. gottschei, whereas S. forticosta had a rare haplotype. Also, genetic differences and gene flows between populations were assessed by analysis of molecular variance and using the pairwise fixation index. Our findings provided insight into the degree of preservation of the species' genetic diversity and could be utilized to enhance the management of endemic species.

• Proceedings of the Korean Society of Applied Entomolohy Conference
• /
• 2005.05a
• /
• pp.188-188
• /
• 2005

• Fisheries and Aquatic Sciences
• /
• v.16 no.4
• /
• pp.243-251
• /
• 2013

Genetic diversity and gene flow patterns in Pollicipes mitella were investigated with a nucleotide sequence analysis of 514 base pairs from the mitochondrial cytochrome c oxidase subunit I gene (COI) in 124 samples collected from six Korean populations. In total, 59 haplotypes were defined by 40 variable nucleotide sites in the COI region. The haplotypes had shallow haplotype genealogy and no geographic associations. All populations had high haplotype diversity (0.909 to 0.979) and low nucleotide diversity (0.0055 to 0.0098). The haplotypes with recently diverged nucleotides were distributed by long-range larvae dispersal among regional populations. The pairwise fixation indices ($F_{ST}$) estimated with the exact test and migration rates indicate that substantial gene flow has occurred among populations as a result of sea currents, except between the Uljin (East Sea coast) and other Korean populations. This suggests that significant genetic differentiation and low migration rates have affected the Uljin population.

• Animal cells and systems
• /
• v.15 no.3
• /
• pp.243-249
• /
• 2011

The genetic diversity and population history of the Asian shore crab, Hemigrapsus sanguineus, were investigated with a nucleotide sequence analysis of 536 base pairs (bp) of the mitochondrial cytochrome c oxidase subunit I gene (COI) in 111 samples collected from four populations in Korea and one in Japan. In total, 28 haplotypes were defined by 27 variable nucleotide sites in the COI region examined. The observed haplotypes had a shallow haplotype genealogy and no geographical associations. Most of the populations had high haplotype diversity (0.656-0.788) and low nucleotide diversity (0.00165-0.00244), and significant negative values for Fu's $F_S$, suggesting rapid and recent population growth from an ancestral population and sudden population expansion. The pairwise fixation indices ($F_{ST}$) estimated with the exact test and the migration rates indicate that substantial gene flow occurs among these populations as a result of sea currents, except between the Yellow Sea coast of Korea (BUA) and the Pacific Ocean coast of Japan (JPA). These two populations (BUA and JPA) showed significant genetic differentiation and low migration rate.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.9 no.1
• /
• pp.137-144
• /
• 2004

The diamondback moth, Plutella xylostella, is notorious because of its extensive potential and actual dispersal ability. Previously, the Korean populations of P. xylostella was extensively collected and analyzed for their genetic population structure using a portion of mitochondrial DNA (mtDNA). One of the postulated characteristics on population genetic structure of the species includes the presence of heterogeneous haplotypes, possibly possessed by some dispersed ones from neighboring countries. In this study, we sequenced ten P. xylostella collected from China (∼2,000 km away from the middle part of Korea) to know the genetic relationships of these to the Korean P. xylostella. Sequence analysis of the identical portion of COI gene resulted in five haplotypes with the sequence divergence ranging from 0.5% (two nucleotides) to 1.1 % (five nucleotides) among them and from 0.7% (three) to 2.5% (11) to the pre-existing 52 Korean haplotypes. Phylogenetic analysis showed that the Chinese P. xylostella were neither clearly separated from the Korean haplotypes nor clustered with one heterogeneous Korean haplotype. This result reinforces the significance of gene flow in this species and suggests to exclude the possibility that the heterogeneous Korean haplotypes may have emigrated from China, where our samples were obtained, although further extensive investigation is required.