• Animal Systematics, Evolution and Diversity
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• v.25 no.1
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• pp.133-136
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• 2009

A ctenostomatous bryozoan, Bantariella bocki is reported from Jejudo Island of South Korea. This is the first report from Korean waters. Each zooid is produced from each kenozooid which arranged in two and originated opposite each other at intervals of about 0.64 mm along the stolon. B. bocki collected from black corals is considered to be a invasive species introduced from Bonin Islands located in the subtropical waters. The redescription, some distributional remarks and illustrations of B. bocki are provided.

• Journal of Species Research
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• v.9 no.3
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• pp.280-287
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• 2020

In the family Crisiidae (Bryozoa: Cyclostomata), 90 species have been recognized worldwide in seven genera: Bicrisia d'Orbigny, 1853, Crisia Lamouroux, 1812, Crisidia Milne Edwards, 1838, Crisiella Borg, 1924, Crisiona Canu & Bassler, 1928, Filicrisia d'Orbigny, 1853 and Unicrisia d'Orbigny, 1853. Four species in Crisiidae are described from 11 localities from 2008 to 2014, resulting in two new distributional records and two new species in Korea. The new additions to the fauna are: Crisia cuneata Maplestone, 1905, C. elongata Milne Edwards, 1838, C. jejuensis n. sp. and Filicrisia cygnus n. sp. A total of seven Korean crisiids with the addition of four species reported herein are recorded and distributed in three genera: Bicrisia, Crisia and Filicrisia. Accordingly, the Korean cyclostomatous bryozoans come to be 12 species, in eight genera, and five families. All of Korean Crisia eburneodenticulata specimens needed to be reexamined, thus this species is tentatively deleted from the Korean bryozoan fauna.

• Journal of Species Research
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• v.11 no.3
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• pp.180-187
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• 2022

We found three fouling bryozoans from the materials collected from seven localities (ports, yacht marina, intertidal and subtidal zones) in the coastal seas of South Korea from 2003 to 2021. These three species, Thalamoporella californica (Levinsen, 1909), Scruparia ambigua (d'Orbigny, 1841), and Tricellaria inopinata d'Hondt and Occhipinti Ambrogi, 1985, and one genus Scruparia Oken, 1815 are newly added to the Korean bryozoan fauna. Of the three species, Scruparia ambigua and Tricellaria inopinata are cosmopolitan or widespread, and Thalamoporella californica is from the East Pacific Ocean in tropical/temperate water. It seems that some of the previously reported T. occidentalis in Korea have a high probability of being T. inopinata. In this study, some Tricellaria occidentalis reported by Seo (2005) are synonymized into T. inopinata. A total of 77 species of fouling bryozoans has been reported in Korea, with three new bryozoans resulting from this study. Descriptions and illustrations of the three fouling bryozoans using scanning electron microscopy are provided in this study.

• Korean Journal of Environmental Biology
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• v.33 no.3
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• pp.352-359
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• 2015

In order to investigate the occurrence of Pectinatella magnifica in Nakdong River, extensive series of sampling was conducted through July to November of 2014. Results revealed that these species show preference to attach themselves on natural substrates over artificial substrates. P. magnifica does not show preference for specified substrates, but itappearthat availability of substrates determines their specific distribution. Considering that most commonly found substrates in Nakdong River were natural substrates such as dead twig, woody plants or aquatic plants, it is possible that high availability of substrates is one of the principal factors which increase the rates of growth and distribution of P. magnifica.

• Journal of Ecology and Environment
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• v.38 no.3
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• pp.375-381
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• 2015

We investigated the influence of summer rainfall on Pectinatella magnifica colonies in lotic ecosystems. Of the examined substrate materials, branches and aquatic macrophytes supported more colonies of P. magnifica than that by stones or artificial materials. The influence of rainfall on P. magnifica colonies differed in accordance with the type of substrate material at each study site. In the Geum River, little difference was noted in the number of P. magnifica colonies on branches before ($mean{\pm}SE$, $24{\pm}7.3$ individuals) and after rainfall ($20{\pm}8.4$ ind.); other substrate types supported fewer colonies of P. magnifica after rainfall. In contrast, in the Miryang River, rainfall had minimal effect on the number of P. magnifica colonies supported by macrophytes ($13{\pm}3.8$ and $12{\pm}4.3$ ind., respectively). Artificial material was more abundant in the Banbyeon Stream where it was able to support more colonies of P. magnifica. We found that the structure of different substrates sustains P. magnifica following rainfall. In the Miryang River, free-floating and submerged plants with a relatively heterogeneous substrate surface were the dominant macrophytes, whereas in the Geum River, simple macrophytes (i.e., emergent plants) were dominant. Therefore, we conclude that the substrate type on which P. magnifica grows plays an important role in resisting physical disturbances such as rainfall.

• 한국해양학회지
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• v.30 no.5
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• pp.480-492
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• 1995

Petrographic investigation has been carried out to determine the composition of the beach sediments and the affecting factors which have controlled their compositional variations from Hyupjae, Aeweol, Iho, Samyang, Hamdeok, Sehwa, Pyoseon, Jungmun, and Hwasun areas along the coast of the Cheju Island. Average mean sizes of the beach sediments are Hyupjae 2.2ø, Aeweol 0.8ø, Iho 1.4ø, Samyang 2.4ø, Hamdeok 1.6ø, Sehwa 1.5ø, Pyoseon 2.1ø, Jungmun 0.4ø, and Hwasun 0.9ø, thus, aries from 0.4 to 2.4ø. The beach sediments from Pyoseon and Hwasun areas are poorly sorted, those from Aeweol and Jungmun areas are moderately sorted and those from the rest of the areas are moderately well sorted. While-colored beach sediments in Hyupjae, Aeweol, Hamdeok, Sehwa, and Pyoseon areas are mostly composed of calcareous shells (more than 85%) such as mollusk, red algae, benthic foraminiferas, etc., whereas volcanic rock fragment is the dominant component of the black-colored beach sediments in Iho, Samyang, and Hwasun areas. Especially, the relatively white-colored beach sediment in Jungmun area, which is on e of the carbonate-dominant areas, shows a higher content of rock fragments than the other carbonate-dominant areas. The beach sediments in Pyoseon area show a high content of carbonate intercalates. Considering the contributions by organisms according to grain size, grains with the size range of 1∼2ø are mostly composed of calcareous red algae fragments, and grains with the size range of 2∼3ø consist of mollusk fragments. It is also notable that bryozoan fragments comprise about 48% of the sediment in Samyang area with the size range of 0∼1ø. The composition of the beach sediments in Cheju Island appears o be controlled by the riverine supply rate of volcanic rock fragments, the lithology of the rocks distributed ear the beaches, the direction of alongshore currents, and the direction of storms, etc.. It is suggested that the beach sediments in Iho and Samyang areas show black color because of the higher supply rate of the volcanic rock fragments from the nearby rivers, whereas those in the rest of the areas show white color due to the relatively lower content of volcanic rock fragments and higher content of carbonate components transported from shallow marine environment. In Hwasun area, the content of volcanic rock fragments is high, and they are directly from the tuffaceous rocks distributed nearby. Also, the volcanic rock fragments in Jungmun area are transported not only from the rivers nearby but also from the nearby tuffs by storm activities. The beach sediment in Pyoseon area contains a high content of carbonate intercalates, which formed in the nearby shallow marine environment through marine cementation. This indicates that active marine cementation occurs in shallow marine environment near Pyoseon area.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.4
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• pp.401-410
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• 2003

Three beaches of the Seogwang-ri coast in the western part of Wu Island, Jeju-do, are solely composed of rhodoliths (red algal nodules). The beach sediments are coarse sand to granule in size and they show the banded distribution according to size. Commonly the larger pebble-sized rhodoliths are concentrated near the rocky coast, resulting from the transportation of the nodules from shallow marine environments by intermittent typhoons. Based on the internal texture of the rhodoliths, it appears that crustose red algae, Lithophyllum sp., is the main contributor for the formation of the rhodolith. The coarse sand to granule-sized grains show that they started to grow from the nucleus as rhodoliths, but the surface was severely eroded by waves. However, the pebble to cobble-sized grains exhibit the complete growth pattern of rhodoliths and sometimes contain other calcareous skeletons. It is common that encrusting red algae are intergrown with encrusting bryozoan. The surface morphology of rhodolith tends to change from the concentric to domal shape towards the outer part. This suggests that the rhodolith grew to a certain stage by rolling, but it grew in more quiet condition without rolling as it became larger. Aragonite and calcite cements can be found in the pores within rhodoliths (conceptacle, intraskeletal pore in bryozoan, and boring), and this means that shallow marine cementation has occurred during their growth. Growth of numerous rhodoliths in shallow marine environment near the Seogwang-ri coast indicates that this area has suitable oceanographic conditions for their growth such as warm water temperature (about 19$^{\circ}C$ in average) and clear water condition due to the lack of terrestrial input of volcanoclastic sediments. Fast tidal current and high wave energy in the shallow water setting can provide suitable conditions enough for their rolling and growth. Typhoons passing this area every summer also influence on the growth of rhodoliths.