• Journal of Species Research
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• v.10 no.1
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• pp.46-56
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• 2021

Diatoms have been used in examining water quality and environmental change in freshwater systems. Here, we analyzed molecular profiling of seasonal diatoms in the Han River, Korea, using the hypervariable region of 18S V1-V3 rRNA and pyrosequencing. Physicochemical data, such as temperature, DO, pH, and nutrients showed the typical seasonal pattern in a temperate region. In addition, cell counts and chlorophyll-a, were recorded at high levels in spring compared to other seasons, due to the diatom bloom. Metagenomic analysis showed a seasonal variation in the phytoplankton community composition, with diatoms as the most frequently detected in spring (83.8%) and winter (69.7%). Overall, diatom genera such as Stephanodiscus, Navicula, Cyclotella, and Discostella were the most frequent in the samples. However, a large number of unknown Thalassiosirales diatoms were found in spring (35.5%) and winter (36.3%). Our molecular profiling revealed a high number of diatom taxa compared to morphological observation. This is the first study of diatoms in the Han River using molecular approaches, providing a valuable reference for future study on diatoms-basis environmental molecular monitoring and ecology.

• Journal of Species Research
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• v.4 no.2
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• pp.145-151
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• 2015

Morphological changes of flowers and insect visitors were observed to investigate pollinator of Caesalpinia decapetala. The flowers of C. decapetala are protandrous. Functionally, the flower is changed from male to female. As a male, pollen grain is released after anther dehisced while style is immature. After completed pollen grain release, the style starts to lengthen. It helps the stigma to easily touch the carpenter bee's thorax covered with pollen grain. At this time, flower functions as a female. The majority of taxa and individuals observed were Hymenoptera. The most frequent visitor was the Xylocopa appendiculata circumvolans, carpenter bee. Carpenter bees exhibited only typical pollinator behavior among flower visitors, with touching reproductive organs and seeking nectar at the same time. The pollination behavior is as follows. Soon after carpenter bees perceived guide mark, they foraged rightward and grasped style and stamens with legs and they inserted proboscis into standard petal to seek nectar. With this behavior, the pollen grains of the male flower transfer to the ventral thorax of the carpenter bee. As the carpenter bee moves to another female flower, the deposited pollen grains are delivered to the stigma.

• Journal of Species Research
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• v.4 no.2
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• pp.159-168
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• 2015

Although airborne pollen is invisible to the eye, it has been known as a major source to respiratory allergic reactions. For this reason, airborne pollen is monitoring in many countries to predict pollen concentration based on locality and season. However, the morphological characteristics of airborne pollen and their potential tendency as an allergen are still obscure. In the present study, we selected 52 airborne pollen samples based on previously reported data and investigated their detail pollen characteristics using LM and SEM. Major airborne pollen in Korea has sorted in 19 families (most angiosperms except four gymnosperm families), and all pollen grains are small to medium in size ($P=17.34-49.86{\mu}m$) apart from the bisaccate pollen grains of Pinaceae ($P=46.49-106.20{\mu}m$). The aperture number and shape vary from sulcate to polyporate. While the inaperture pollen has found only in gymnosperm (Cupressaceae and Taxaceae), triporate or polyporate is common pollen type in angiosperm. The sexine ornamentations could divide into several types, but the most sculpturing types are inconspicuous like psilate, rugulate and granulate. Reticulate pollen grains as a semitectum have occurred the species of genera Platanus and Fraxinus only. To estimate the possible relationships between pollen features and allergen, the results are discussed in botanical context.

• Journal of Species Research
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• v.6 no.spc
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• pp.227-246
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• 2017

A study of the Cladocera (Crustacea: Branchiopoda) from the Korean Peninsula resulted in the checklist of Jeong et al. (2014). Several sampling campaigns conducted by our team since 2014, with the framework of the programs supported by the National Institute of Biological Resources (NIBR), have resulted in a considerable increase in the number of water bodies studied in South Korea. In this report, seven new records for the Korean Peninsula are provided: (1) Macrothrix vietnamensis Silva-Briano, Dieu and Dumont, 1999; (2) Disparalona chappuisi (Brehm, 1931); (3) Pleuroxus(Picripleuroxus) quasidenticulatus (Smirnov, 1996); (4) Acroperus africanus Neretina and Kotov, 2015; (5) Alona ossiani herricki Sinev, 2013; (6) Coronatella trachystriata (Chen, Zhang and Liu, 1994); (7) Leydigia louisi Jenkin, 1934. Most of these taxa belong to the southern thermophilic complex. In addition several populations of Pleuroxus (Picripleuroxus) denticulatus Birge, 1879 and Pseudochydorus globosus (Baird, 1843) were re-studied, and their presence in Korea is confirmed. Through increased collection efforts and the application of molecular methods we are confident that more new records of Korean fauna will be published in the near future.

• Journal of Species Research
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• v.12 no.spc
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• pp.1-69
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• 2023

This study aims to establish a comprehensive, synthetic inventory system for the fauna and flora of Dokdo Island, Republic of Korea, which has been conducted by a specialized research group consisting of more than 50 experts. The research was conducted over five years(2015-2019) and supported by the National Institute of Biological Resources, Ministry of Environment, Republic of Korea. All possible publications on the fauna and flora of Dokdo Island over the last 68 years from 1952 to 2020 were reviewed. As a result, 1,302 species were found on Dokdo Island during the study period. An updated list of 1,963 species was created. This is expected to be of great help for the conservation and national publicity of important indigenous biological resources of Dokdo Island.

• Journal of Species Research
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• v.2 no.2
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• pp.159-166
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• 2013

Typical of large, oligotrophic lakes, Lake H$\ddot{o}$vsg$\ddot{o}$l, Mongolia, exhibits complex morphometry which should support a spatially heterogeneous community of benthic macroinvertrates. The lake also exhibits a broad range of land uses. Based on the variation in land use and complex physical habitat of the lake (e.g. substrate variation and presence of affluent streams in bays), we asked two questions. First, does density of total benthic macroinvertebrates vary between different bays in Lake H$\ddot{o}$vsg$\ddot{o}$l? Second, does density of individual benthic taxa vary by bay? Samples collected in 1997, the last year for benthic sampling of the lake, were designed to test for variation in macroinvertebrate density between bays and can now be used to establish baseline variation in density for future studies. A total of 56 Ponar grab samples were analyzed from six bays in Lake H$\ddot{o}$vsg$\ddot{o}$l. Results of a general linear model analysis of variance showed that total density of macroinvertebrates varied only slightly between bays of the lake, but that most individual taxa showed significant variation between bays. Variation in density for most taxa was linked to substrate composition rather than other geographic or physical variables in the lake. Recent increases in grazing intensity and ecotourism along the shores should be managed to reduce the nutrient load into the lake to avoid impairment of the benthic biota of this unique, ancient ecosystem.