• ALGAE
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• v.32 no.3
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• pp.171-179
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• 2017

The strictly freshwater red algal order Batrachospermales has undergone numerous taxonomic rearrangements in the recent past to rectify the paraphyly of its largest genus Batrachospermum. These systematic investigations have led to the description of new genera and species as well as re-circumscription of some taxa. Specimens collected from two locations in the southeastern USA were initially identified as being allied to Batrachospermum sensu lato, but could not be assigned to any recognized species. Representative rbcL (plastid) and COI-5P (mitochondrion) sequences showed these specimens to be similar to each other and not closely matching the previously published sequence data for other Batrachospermum taxa. Comparison of sequence variation and morphology with a broader range of batrachospermalean taxa resulted in the proposal of a new monotypic genus Lympha mucosa gen. et sp. nov. to accommodate these specimens. Lympha mucosa is sister to members of a newly described genus Volatus, but the two genera are easily distinguished based on straight versus curved, twisted or spirally coiled carpogonial branch, respectively. This new taxon has morphological similarities to Batrachospermum sections Turfosa and Virescentia, but can be differentiated based on genetic divergence in rbcL and COI-5P as well as a combination of morphological characters: dense, compressed whorls, axial carposporophytes with a single type of gonimoblast filament; cortication of the main axis closely appressed; and short, straight carpogonial branch arising from the pericentral cell and carpogonia with unstalked, lanceolate trichogynes. This new taxon adds to the freshwater red algal diversity of the southeastern USA, a region already known for biodiversity and high endemism of the aquatic flora and fauna. It is also a relevant new addition to the taxonomic knowledge of the freshwater red algal Batrachospermales.

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

• Parasites, Hosts and Diseases
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• v.45 no.3
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• pp.181-190
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• 2007

The phylogenie relationships existing among 14 parasitic Platyhelminthes in the Republic of Korea were investigated via the use of the partial 28S ribosomal DNA (rDNA) D1 region and the partial mitochondrial cytochrome c oxidase subunit 1 (mCOI) DNA sequences. The nucleotide sequences were analyzed by length, G + C %, nucleotide differences and gaps in order to determine the analyzed phylogenie relationships. The phylogenie patterns of the 28S rDNA D1 and mCOI regions were closely related within the same class and order as analyzed by the PAUP 4.0 program, with the exception of a few species. These findings indicate that the 28S rDNA gene sequence is more highly conserved than are the mCOI gene sequences. The 28S rDNA gene may prove useful in studies of the systematics and population genetic structures of parasitic Platyhelminthes.

• ALGAE
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• v.30 no.1
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• pp.15-33
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• 2015

When the generitype Centroceras clavulatum, a presumed cosmopolitan warm temperate to tropical red alga, was discovered to have a biogeographic distribution limited to the Pacific Ocean using molecular and morphological evidence, the taxonomy in the genus Centroceras was thrown into chaos worldwide. An analysis of what species was, or were, previously identified as C. clavulatum in Bermuda is the focus of the present molecular (COI-5P, rbcL) and morphological study. Two novel species are proposed, C. arcii sp. nov. and C. illaqueans sp. nov., and the distributions of three taxa recently segregated in the 'C. clavulatum complex' of the western Atlantic, C. gasparrinii, C. hyalacanthum, and C. micracanthum, have been expanded to include Bermuda. C. arcii is shown to be morphologically cryptic with C. micracanthum, and remains best distinguished by its COI-5P barcode sequence.

• Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.44-48
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• 2009

Nucleotide sequences of about 500 bp from the 5' end of mitochondrial (mt) DNA Cytochrome Oxidase I (COI) were analyzed to estimate the genetic variation between wild and cultured populations of the ascidian Halocynthia roretzi from two sites along the coast of Korea. A total of 25 haplotypes were defined by 21 variable nucleotide sites in the examined COI region. Genetic diversity (haplotype diversity and nucleotide divergence) of wild populations was higher than that of the cultured population. These data suggest that reduced genetic variation in the cultured population may have results from bottleneck effect caused by the use of a limited number of parental stock and pooling of gametes for fertilization. Pairwise population $F_{ST}$ estimates inferred that wild and cultured populations were genetically distinct. The combined results suggest that sequence polymorphism in the COI region would be preferable for estimating the genetic diversity of ascidian populations.

• Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.48-55
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• 2024

The study assessed the utility of mitochondrial DNA for identifying a deceased rorqual discovered off the western coast of India. Both the COI and Cytb genes exhibited remarkable 99-100% similarity with the GenBank sequence of Balaenoptera musculus through a global BLAST search, confirming their affiliation with this species. Inter-species genetic distances for COI and Cytb genes ranged from 6.75% to 9.80% and 7.37% to 10.96% respectively, compared with other Balaenopteridae species. The Bayesian phylogenies constructed based on both COI and Cytb genes demonstrated clear and separate clustering for all Balaenopteridae species, further reaffirming their distinctiveness, while concurrently revealing a cohesive clustering pattern of the generated sequences within the B. musculus clade. Beyond species confirmation, this study provides valuable insights into the presence of live and deceased B. musculus individuals within Indian marine ecosystems. This information holds significant potential for guiding conservation efforts aimed at safeguarding Important Marine Mammal Areas (IMMAs) in India over the long term.

• International Journal of Industrial Entomology and Biomaterials
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• v.24 no.1
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• pp.41-47
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• 2012

The Scarites aterrimus (Coleoptera: Carabidae) dwells exclusively on coastal sandy dunes. Previously, we investigated the nation-wide magnitude and nature of genetic diversity of the species using mitochondrial COI gene and found moderate to low magnitude of sequence diversity, the presence of closely related haplotypes, and relatively high gene flow estimate. Based on these observations we concluded that the species had no historical barriers that bolster genetic subdivision and possible population decline. In this study, we additionally sequenced mitochondrial COII gene from 23 individuals collected from 9 Korean localities to confirm previous findings. Sequencing of 688 bp COII gene provided 5 haplotypes ranging in sequence divergence from 0.145% to 0.291% (1 ~ 2 bp), further confirming low sequence divergence of the species. Gene flow estimates and genetic diversity estimates also support the previous findings that there had been no historical barriers that bolster genetic subdivision.

• Korean Journal of Ecology and Environment
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• v.54 no.3
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• pp.229-239
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• 2021

Thamnaconus modestus, distributed in the Northwest Pacific, has high economic value and is used in various seafood. In this study, the morphological and genetic characteristics of T. modestus and T. septentrionalis were compared and analyzed. We observed the external and internal morphology of T. modestus, sketched skeletal elements, and analyzed phylogenetic evolutionary relationships using the cytochrome c oxidase subunit I (COI) gene on mitochondrial DNA compared to T. septentrionalis. The T. modestus observed in this study had blackish-brown patterns irregularly scattered on the gray-brown body, and the fins were blue-green. Genetic analysis results based on the COI sequences of T. modestus showed seven types of base sequence variation; however, the homology was more than 98.8%. In addition, as a result of comparison of the COI nucleotide sequences and phylogenetic analysis in Tetraodontiformes, two T. septentrionalis sequences (JN813099, MW485059) were similar to T. modestus with 99% homology, and the other two T. septentrionalis sequences (EF607583, KP267619) were similar to those of species belonging to another genus Thamnaconus with 95% homology with T. modestus. It was not easy to classify the species based on morphological characteristics, and phylogenetic analysis between T. modestus and T. septentrionalis confirmed the difference in classification. These results provide the external and internal morphology of T. modestus and will be used as important information for the taxonomic study of T. modestus and T. septentrionalis.

• Animal Systematics, Evolution and Diversity
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• v.36 no.4
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• pp.400-407
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• 2020

An epialtid spider crab, Naxioides robillardi (Miers, 1882), is known as widely distributed in Indo-West Pacific region include Japanese waters. Four specimens of epialtid crabs were collected from adjacent waters of Jejudo Island and identified as N. robillardi. This species can be grouped into two forms such as N. robillardi form typical and N. robillardi form mammillata according to morphological features of carapace, gastric spine, and chela. Morphological characters of all Korean specimens well agree with the form mammillata in general. In this paper, morphological diagnosis and illustrations of newly collected N. robillardi are provided. DNA barcode sequence of COI region is also determined for the first time.

• Journal of Species Research
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• v.12 no.1
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• pp.27-37
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• 2023

Kushia zosteraphila Harris V.A. & Iwasaki, 1996 is newly collected and described from macroalgae in the intertidal region of Gijang-gun, along the southeastern coastal region of Korea. Kushia zosteraphila can be distinguished from congeners by following morphological characteristics: the length of the first dorsal seta similar with the second dorsal seta of female P5, the length to width ratio of the female caudal ramus, and the presence of a conspicuous comb on the accessory lobe of the male antennule. Although there are some minor discrepancies, the main diagnostic characteristics of the specimen from the study area are well-matched with the original description. We herein provide detailed morphological descriptions and illustrations of this species. According to a survey of the location of the reported porcellidiid species in Korea, this specimen is the second record in Korean waters of the genus Kushia. A key to species of the family Porcellidiidae in Korea is provided. A partial sequence of the mitochondrial COI gene was obtained and provided as a DNA barcode for this species.