• Environmental Engineering Research
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• v.19 no.4
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• pp.317-329
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• 2014

The diversity of cyanobacteria in Sri Lanka was studied in different water reservoirs, paddy fields, brackish water and tsunami affected areas using light microcopy, 16S rRNA sequences, followed by phylogenetic analysis. Based on light microscopy, 24 genera were identified from environmental samples belonging to the orders Chroococcales, Oscillatoriales, Pleurocapsales and Nostocales. In cultures, 33 genera were identified from all five cyanobacterial orders, including Stigonematales. Based on 16S rRNA gene sequences and their morphology, two isolates were identified up to species level, 72 to genus level, one isolate up to family and 11 up to order level. Twelve isolates couldn't be assigned to any taxonomic level. The results of 16S rRNA gene sequences along with the phylogenetic analysis indicated that some cyanobacterial isolates could be accommodated to genus or order level. The 16S rRNA sequence analysis data in this study confirmed that order Nostocales and order Pleurocapsales cyanobacteria are monophyletic while orders Chroococcales, Oscillatoriales and Stigonematales cyanobacteria are polyphyletic. Polyphasic approach including the combination of light microscopy, cultures and the analysis of 16S rRNA gene sequences provide a promising approach to ascertain the diversity of cyanobacteria in different habitats.

• ALGAE
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• v.22 no.1
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• pp.1-10
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• 2007

To gain insights into the phylogenetic relationships of genus Staurastrum and Staurodesmus, we analyzed nuclearencoded small subunit rDNA of 82 strains, and chloroplast atpB gene sequences of 44 strains belonging to three genera (Staurastrum, Staurodesmus, Cosmarium). Excluding the Staurastrum muticum and S. orbiculare, forty five strains of genus Staurastrum formed a well supported clade. It was shown that with no cell wall sculpture and processes, these two species have a strong phylogenetic relationship with genus Staurodesmus. Therefore, it is strongly recommended to transfer Staurastrum without processes and cell wall sculpture into Staurodesmus. S. obsoletus is a taxa that is transferred from Cosmarium. But, from this study, it has shown a phylogenetic relationship with Cosmarium. Therefore, this species is strongly recommended to transfer back to Cosmarium instead of Staurodesmus. As it was studied before, genus Staurastrum has shown monophyletic. Since the genus taurodesmus groups with Cosmarium, they were shown to be polyphyletic.

• ALGAE
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• v.35 no.4
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• pp.349-359
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• 2020

Specimens of Umbraulva with greenish iridescent were collected in the subtidal zone of Jeju Island, Korea. To investigate these collections, plastid rbcL and tufA sequencing of six greenish iridescent specimens, including four Umbraulva japonica, were analyzed. Phylogenetic analysis of a concatenated multigene alignment found that the greenish iridescent specimens belonged to a yet undescribed taxon in the genus Umbraulva. We herein propose the name Um. yunseulla sp. nov. for this specimens. Juveniles of Um. yunseulla sp. nov. resemble the generitype Um. japonica in appearance, showing globular to subglobular and funnel-shaped habits, but the blades of this new species are not split longitudinally like those of Um. japonica. Although the multigene phylogenetic tree showed the polyphyletic clade of Umbraulva with respect to the genus Ryuguphycus, Um. yunseulla sp. nov. formed a clade with Um. japonica and Um. amamiensis by weak bootstrap support. These findings, Um. yunseulla sp. nov., highlight the importance of studying the biodiversity of subtidal habitats from Jeju Island, Korea and further emphasize the need for investigations of macroalgae in the mesophotic zone around the Korean peninsula.

• Fisheries and Aquatic Sciences
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• v.25 no.3
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• pp.158-166
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• 2022

The complete mitochondrial genome of Tremoctopus violaceus was sequenced to analyze its organization and phylogenetic status within the order Octopoda. The mitochondrial genome of T. violaceus had a structure and organization similar to that of other Octopoda. The content of the nucleotides A, C, G, and T was 31.68 %, 7.71 %, 20.02 %, and 40.58 %, respectively. All protein-coding genes (PCG) began with the ATG codon, excluding ND4 and ATP6, which began with ATC and ATT, respectively, and terminated with TAG, TAA, TA, or T. Codons for isoleucine were the most used codons, whereas those for arginine were used the least. Two extra tRNAs, trnN and trnL, were found in the control region. These tRNAs have a D-armless structure. The control region had excess A + T content (83.16 %) and a stem-loop structure with two elements, which is reported for the first time in Octopoda by our study. Bayesian inference using 13 PCG revealed that Octopus and Octopodidae were polyphyletic, and that Tremoctopodidae diverged relatively earlier within Octopoda. The mitochondrial genome of T. violaceus and its characteristics may help to understand the evolutionary history of Octopoda and establish a marine biodiversity conservation strategy.

• Korean Journal of Plant Taxonomy
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• v.52 no.3
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• pp.127-143
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• 2022

This study was conducted to clarify the phylogenetic position and relationships of Korean Poaceae taxa. A total of 438 taxa including 155 accessions of Korean Poaceae (representing 92% and 72% of Korean Poaceous genera and species, respectively) were employed for phylogeny reconstruction. Sequence data of eight chloroplast DNA markers were used for molecular phylogenetic analyses. The resulted phylogeny was mostly concordant with previous phylogenetic hypotheses, especially in terms of subfamilial and tribal relationships. Several taxa-specific indels were detected in the molecular phylogeny, including a 45 bp deletion in rps3 (PACMAD [Panicoideae, Arundinoideae, Chloridoideae, Micrairoideae, Aristidoideae, Danthonioideae] clade), a 15 bp deletion in ndhF (Oryzeae + Phyllorachideae), a 6 bp deletion in trnLF (Poeae s.l.), and two (17 bp and 378 bp) deletions in atpF-H (Pooideae). The Korean Poaceae members were classified into 23 tribes, representing eight subfamilies. The subfamilial and tribal classifications of the Korean taxa were generally congruent with a recently published system, whereas some subtribes and genera were found to be non-monophyletic. The taxa included in the PACMAD clade (especially Andropogoneae) showed very weak and uncertain phylogenetic relationships, presumably to be due to evolutionary radiation and polyploidization. The reconstructed phylogeny can be utilized to update the taxonomic positions of the newly examined grass accessions.

• Mycobiology
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• v.46 no.2
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• pp.101-113
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• 2018

Lichen genus Stereocaulon (Schreb.) Hoffm is distributed throughout the world. Although 15 Stereocaulon species have been recorded in Korea, no detailed taxonomic or revisionary research has been conducted for nearly two decades. In this study, we collected 260 putative Stereocaulon spp. samples and identified the species based on morphological, chemical, and molecular characteristics. From the collected samples, 10 species of Stereocaulon were identified, nine of which had already been reported, although this was the first report for the tenth, S. octomerellum Hue, in Korea. General characteristics of Stereocaulon spp. include coralloid phyllocladia and tubercular cephalodia; however, the specimen first collected in Korea was a rare species with tomentum on the pseudopodetia. The specimen of S. octomerellum is characterized by the presence of a primary thallus, granule to short coralloid phyllocladia, and pseudopodetia up to 1 cm in size, with tubercular cephalodia. To determine the phylogeny of the specimens, we compared the ITS sequences of ribosomal DNA and the b-tubulin gene sequences. Phylogenetic analysis showed that the Korean Stereocaulon species were monophyletic and placed in the previous phylogenetic classification. Species of S. intermedium and S. exutum, however, were polyphyletic, and are morphologically variable and widespread species. Overall, we present here detailed morphological and chemical descriptions of each species identified and a revised key of all known Stereocaulon species in South Korea.

• Korean Journal of Ichthyology
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• v.22 no.4
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• pp.273-278
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• 2010

Partial nucleotide sequences of nuclear protein-coding recombination activating gene 1 (RAG1) gene of two Abbottina and five Microphysogobio species residing in Korea were analyzed to elucidate the molecular phylogenetic position of A. springeri Banarescu and Nalbant. In RAG1 tree A. rivularis was clearly separated from the monophyletic lineage composed of A. springeri, Biwia zezera and Microphysogobio species. Within this lineage B. zezera showed sister-group relationship to the monophyletic group composed of A. springeri and five Microphysogobio species. Thus, our phylogenetic tree revealed the polyphyletic nature of two Abbottina species from Korea, which result is well congruent with the previous phyletic assumption based on osteological features. The current classification of Abbottina and Microphysogobio based on morphological criteria, such as the presence or absence of papillae on lips and size of swim bladder with or without encapsulation, does not reflect their true evolutionary history.

• Journal of Life Science
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• v.14 no.4
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• pp.593-607
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• 2004

The nucleotide sequence for a nuclear-encoded small subunit rDNA (SSU rDNA) was determined for 43 species of the class Dinophyceae, including harmful algae Cochlodinium polykrikoides and Gyrodinium aureolum. These sequences and data analyses were performed by parsimony, distances and maximum likelihood methods in PHYLIP (Phylogenetic Inference Package) version 3.573c. The species Noctiluca scintillans, Gonyaulax spinifern and Crypthecodinium cohnii occupied a basal position within the Dino- phyceae in our analyses. The genera Alexandrium and Symbiodinium were monophyletic (supported by a bootstrap value of >70%), whereas the genera Gymnedinium and Gyrodinium formed polyphyletic nodes, for which bootstrap support was strong (>70%) in the neighbor-joining and maximum likelihood methods except for the PHYLIP parsimony analysis (=59%). The sequence divergence between G. aureolum and G. dorsum/ G. galathenum was the largest at 7.4% (45 bp), whereas G. aureolum and G. mikimotoi showed an extremely low value of genetic divergence of 0.9% (5 bp). The genetic divergence between C. polykrikoides and G. aureolum was a low value of 5.2% (31 bp). In the phylogenetic analysis, the placement of G. aureolum and C. polykrikoides was closer to the genus Gymnodinium than to the genus Gyrodinium, which was supported by a moderate bootstrap value.

• ALGAE
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• v.33 no.4
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• pp.291-304
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• 2018

Lyngbya C. Agardh ex Gomont is a nonheterocytous cyanobacterial genus whose evolutionary history is still poorly known. The traditionally defined Lyngbya has been demonstrated to be polyphyletic, including at least five distinct clades, some of which have been proposed as new genera. Intraspecific diversity is also clearly underestimated in Lyngbya due to the lack of unique morphological characters to differentiate species. In this study, we describe the new genus Capillus T. A. Caires, C. L. Sant'Anna et J. M. C. Nunes from benthic marine environments, including two new Brazilian species (here described as C. salinus T. A. Caires, C. L. Sant'Anna et J. M. C. Nunes, and C. tropicalis T. A. Caires, C. L. Sant'Anna et J. M. C. Nunes), and two species yet to be described, one of them from India (Capillus sp. 2.1), and the other from United States of America, based on strain PCC 7419. Capillus species presented cross-wise diagonal fragmentation, assisted or not by necridic cells, which has not been previously mentioned for Lyngbya. Ultrastructural analyses showed that C. salinus and C. tropicalis have numerous gas vesicles, which are rarely described for benthic marine species. The new genus formed a well-supported clade, and the D1-D1' and Box B secondary structures of internal transcribed spacer also supported the proposal of its new species. These findings help to clarify the diversity of species in the Lyngbya complex and the taxonomy of the group, and highlight the need of further floristic surveys in tropical coastal environments, which remain poorly studied.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.3
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• pp.141-150
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• 2015

Dinoflagellates are ubiquitous and important primary producers in the oceans. They have diverse trophic modes, i.e., phototrophic, heterotrophic, and mixotrophic modes and thereby, play important ecological role in marine microbial food-web. While many studies have been focused on planktonic dinoflagellates in pelagic ecosystems, benthic, sand-dwelling dinoflagellates that inhabit in intertidal zone have been very poorly documented worldwide. We investigated biodiversity, occurrence, and molecular phylogeny of benthic, sand-dwelling dinoflagellates from the intertidal flat of Dongho, west coast of Korea during low-tide, monthly from November 2012 to February 2014. About 27 species of 13 genera in orders Gonyaulacales, Gymnodiniales, Peridiniales, Prorocentrales have been identified, of which members in the genus Amphidinium constituted a major part of the sand-dwelling dinoflagellates in this area. A total of 34 isolates from 16 species of the sand-dwelling dinoflagellates were isolated from Dongho, Mohang, Gamami, and Songho in the west coast and Hyupjae in Jeju of Korea, their 28S rDNA sequences were successfully amplified, and applied for molecular phylogenetic analyses. In the 28S rDNA phylogeny, Amphidinium species diverged across three major clusters within the order Gymnodiniales and formed polyphyletic group. Based on the unambiguously aligned partial 28S rDNA sequences including variable D2 region, the genotypes of Amphidinium mootonorum Korean strains greatly differed from that of Canadian strain with 19.2% of pairwise nucleotide difference, suggesting that further ultrastructural studies may provide additional characters to clearly separate these genotypes. Two potential toxic species, Amphidinium carterae and A. operculatum appeared occasionally during this study. Quantitative assessment and toxicity of those species should be addressed in the future.