• Animal Systematics, Evolution and Diversity
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• v.27 no.3
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• pp.213-219
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• 2011

Some echinoids were collected from the coast of Gangwon-do during the period from November 2008 to July 2011 and were identified on the basis of morphological characteristics and molecular analysis of cytochrome oxidase subunit I mitochondrial DNA. Among them, Strongylocentrotus pallidus (Sars, 1871) belonging to the family Strongylocentrotidae of the order Camarodonta is reported for the first time in Korea and is redescribed. The genetic differences ranged from 0.038 to 0.139 between S. pallidus and four other species of genus Strongylocentrotus, but ranged from 0.002 to 0.005 between Korean specimens and GenBank data of S. pallidus. This species is widely distributed in cold sea water along the western part of the North Pacific and the Northwest Atlantic.

• Animal Systematics, Evolution and Diversity
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• v.33 no.3
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• pp.195-199
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• 2017

A sea cucumber was collected from Gonghyeonjin in the East Sea of Korea at a depth of 50 m on 22 June 2011 and was identified as Psolus phantapus (Strussenfelt, 1765). This species belongs to the family Psolidae of the order Dendrochirotida based on morphological characteristics and mitochondrial cytochrome c oxidase subunit I sequence analysis. Psolus phantapus, which widely distributes in the Arctic and North Atlantic Oceans, is newly recorded in the Korean fauna. Two Psolus species including the previously reported P. squamatus are recorded in the East Sea of Korea.

• Journal of Mechanical Science and Technology
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• v.15 no.5
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• pp.665-670
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• 2001

The interaction of a travelling shock with the shear layer of a flat plate is studied computationally. The Euler and Navier-Stokes equations are solved numerically on quadrilateral unstructured adaptive grids. The flat plate is installed horizontally on the central axis of a shock tube. The shear layer is first created by two shock waves at different speeds splitted by a flat plate. A series of small vortices is developed as a consequence in the shear layer. The shock wave reflected at the end wall impinges the shear layer. The complicated shock dynamics in the evolution to the pseudo-steady state is represented with the morphological transformation of a planar shock into an oblique shock.

• Animal Systematics, Evolution and Diversity
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• v.24 no.3
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• pp.323-326
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• 2008

Some sea urchins were collected from the subtidal rocky bottom of Munseom near Seogwipo, Jejudo Island by SCUBA diving from April to May, 2008 and identified on the basis of their morphological characteristics. Among them, Tripneustes gratilla (Linnaeus, 1758) of Family Toxopneustidae was newly recorded from Korea and redescribed on the specimen collected at a depth of 25 m between Munseom and Sekkiseom. The detailed morphological description was presented with the photographs. This species was characterized by the very naked median areas of ambulacral and interambulacral portions and this genus was the first record in Korea. Eighteen echinoids are so far recorded in Jejudo Island, Korea.

• Animal Systematics, Evolution and Diversity
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• v.30 no.2
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• pp.132-136
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• 2014

Five sea cucumbers were collected from Gisamun and Gonghyeonjin of Gangwon-do, in the East Sea, Korea from 27 December 2009 to 14 November 2012. These specimens were classified as Synallactes nozawai Mitsukuri, 1912 belonging to the family Synallactidae of order Aspidochirotida based on morphological characteristics. The family, genus and species are recorded for the first time from Korea. The distinct morphological characteristics of this species are as follows: body flexible, with thin gelatinous body wall; presence of numerous tubercles along dorsal ambulacra table of body wall consisted of three- or four-armed disk and a spire-form pillar. This species usually inhabits the deep sea and is distributed in the Northwest Pacific from northern Japan to Bering Sea.

• Animal Systematics, Evolution and Diversity
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• v.30 no.3
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• pp.206-214
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• 2014

Two monstrilloid copepod species belonging to the genus Monstrilla Dana are newly recorded from Korea: M. grandis Giesbrecht, 1891 and M. hamatapex Grygier and Ohtsuka, 1995. Specimens were obtained from inshore waters around the coasts of South Korea, using a light trap installed at quays and wharves overnight. Based on the Korean specimens, the two species are redescribed, with brief accounts of their affinities and morphological variabilities. Remarkable morphological discrepancies are confirmed in female leg 5 of M. grandis between type material from Southern Hemisphere and European and Asian specimens, which raise a strong doubt on their conspecificity. Korean specimens of M. hamatapex well coincide with the type specimens from Japan, except for some variations in the setal armature of leg 5 and antennules. This is the second taxonomic paper on the monstrilloid copepods in Korea, and the genus Monstrilla is newly added to Korean fauna.

• Animal Systematics, Evolution and Diversity
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• v.34 no.4
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• pp.208-214
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• 2018

The genus Luidia belongs to the family Luidiidae in the order Paxillosida. It is a common littoral taxon, and the depth range of the Korean fauna is generally 0-100 m. However, specimens of Luidia were collected from Jeju Island in Korea at 150-160 m depth and identified as Luidia sagamina sagamina $D{\ddot{o}}derlein$, 1920. This species is determined by morphological characteristics and mitochondrial cytochrome c oxidase subunit I sequence analysis. Luidia sagamina sagamina is a very rare sea star in worldwide and it only collected previously from Sagami Bay, Japan, and is newly reported in Korea. Four species of Luidia, including L. s. sagamina, are recorded in the Korean fauna.

• Animal Systematics, Evolution and Diversity
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• v.34 no.4
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• pp.215-219
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• 2018

Protochitonidae Ashby, 1925 is a family of small to medium sized chitons that includes a single fossil genus and two extant genera. Of the two extant genera, Deshayesiella Carpenter in Dall, 1879 contains 5 described species. Although most Deshayesiella species are known to be found in deep sea habitats(over 100 m), D. curvata (Carpenter in Pilsbry, 1892) is found from shallow waters(1-20 m). In this study, we provide details of microstructure of shell and radula characters using scanning electron microscopy and morphological features of D. curvata, and its partial sequence of mitochondrial DNA cox1 gene as DNA barcode sequence. In addition, we compare morphological differences of D. curvata from other congeneric species.

• Animal Systematics, Evolution and Diversity
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• v.33 no.2
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• pp.131-135
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• 2017

Asteroid specimens of the genus Luidia were collected at a depth of 95-100 m in the Korea Strait by bottom trawling in April 2016. The specimens were identified as Luidia avicularia Fisher, 1913 (Luidiidae: Paxillosida) based on morphological characteristics and molecular phylogenetic analyses, and the species is new to the Korean fauna. A 648-bp partial nucleotide sequence of mitochondrial cytochrome c oxidase I (mt-COI) gene was obtained from Korea, and then was compared to sequences of related species stored in GenBank using molecular phylogenetic analyses. No sequence differences were detected between the L. avicularia mt-COI gene sequences from Korea and China, and the species described in this report was clearly distinct from L. maculata, which was previously reported in Korean fauna. Three Luidia species have been reported in Korea.

• Animal Systematics, Evolution and Diversity
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• v.37 no.4
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• pp.345-348
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• 2021

The genus Eucephalobus Steiner, 1936, belonging to the family Cephalobidae Filipjev, 1934 (Cephalobomorpha), represents a group of bacterial feeding nematodes. Although this group is cosmopolitan and species-rich, only two species have been reported from South Korea. Eucephalobus iaculocaudatus Bostrom and Holovachov, 2011 was collected from natural forest in Chungcheongbuk-do, South Korea. This species shows typical morphological characters of the genus Eucephalobus, including a bicornuate labial probolae, cephalic probolae absent and three lateral incisures. However, E. iaculocaudatus is distinguished from other Eucephalobus species by conoid tail with a harpoon-shape mucro in female and ragged mucro in male. In this study, detailed morphological characters and morphometrics of E. iaculocaudatus are described and illustrated based on optical microscopy.