• Animal cells and systems
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• 제3권4호
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• pp.359-363
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• 1999

Urochordates, the most primitive group in phylum Chordata, are mostly sessile as adults although some are free living. Presently, the ancestral stock of urochordates as weir as chordates has been the focus of interest and two conflicting hypotheses have been presented. A free swimming ancestor is one and a sessile, filter feeding ancestor is the other. To clarify the phylogenetic relationships within the urochordates, 22 urochordates and five others as outgroups were used. And we applied neighbor joining, maximum likelihood, and maximum parsimony methods to partial 18S rDNA sequences. The inferred phylogeny in all analyses indicates that order Aplousobranchia of class Ascidiacea appears to be the most ancestral group among urochordates. But it is not clear for the low bootstrap value. The remaining two orders of ascidians, Phlebobranchia and Stolidobranchia, form monophyletic groups respectively, which are well supported by high bootstrap values. These two orders are closer to classes of Thaliacea and Appendicularia than to the Aplousobranchia. While class Appendicularia is strongly supported by the monophyletic group, the phylogenetic position of class Thaliacea is unclear in this study.

• Animal Systematics, Evolution and Diversity
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• 제13권2호
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• pp.93-102
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• 1997

조간대와 수심 20m 미만의 조하대 모래틈에서 채집한 해양 완보류 2신종 - Batillipes longispinosus n. sp., B. orientalis n. sp. - 을 기재한다. 이들 2신종은 미성숙 개체와 성체 모두에서 몸통 뒷부분에 돌기가 없으며 머리에 난 여러 돌기들이 길다는 점, 제 4다리위에 긴돌기를 가진다는 점에서 특징적이다. B. longispinosus n. sp.는 Batillipes 속에 기록된 21종 중에서 B. tubernatis Pollock과 가장 유사하나 4번째 다리에 긴 돌기를 가지는 점에서 다르다. 또한 B. orientalis n. sp. 는 몸 측면 돌기를 가진다는 점에서 B. roscoffensis Kristensen와 닮았으나 머리의 모양과 4번째 다리에 긴 돌기를 가지는 점에서 뚜렷하게 구별된다.

• Animal Systematics, Evolution and Diversity
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• 제11권3호
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• pp.329-334
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• 1995

1992년부터 1994년까지 우리나라의 연안에서 채집된 참서대과 어류 6종의 상두개골계(epicranical bony system) 에 대해 비교 검토하였다. 상두개골 가운데 erisma 와 frontal element 의 발달정도에 따라 1. Paraplagusia japonica, 2.Cynogossus joyneri 와 C.robustus, 3.c. semilaveis와 C. abbreviatus, 4.C. interruptus 의 4 group 으로 구분되엇고, erisma를 지지하는 proximal radials 의 수에서도 P.japonica와 C. robustus 가 10-11개, C. joyneri 10-12 . C. semilaevis 9-11. C. abbreviatus 9-10 , C. interruptus 7-8개로 종간에 많은 차이를 나타냈다. 이러한 골격의 형태적 차이는 종간의 유연관계를 나타내는데 중요한 형질로 사료된다.

• Animal Systematics, Evolution and Diversity
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• 제11권3호
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• pp.389-408
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• 1995

풀게의 유생을 수온 25$^{\circ}C$, 염분농도 33.3$\textperthousand$, 광주기 14:10 h light:dark 의 실험실 조건하에서 사육하였다. 사육 결과 본 종은 5 zoea와 1 megalopa 유생기를 가지며, 부화 후 megalopa와 제1기 crab까지는 최소 18일과 29일이 걸렸다. 전체 유생기의 형태적인 특징을 상세히 기술 및 도시하였다. 풀게 유생과 참게아과내의 이미 보고된 유생 상호간에 구별될 수 있는 형태적인 특징들에 대하여 토의하였다. 특히, 풀게속의 megalopa 유생 상호간 형태적 특징을 도표화하였다.

• Animal Systematics, Evolution and Diversity
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• 제12권2호
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• pp.91-99
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• 1996

실험실에서 사육된 밤게의 유생은 2조에아 유생기와 1메가로파 유생기를 가졌고, 조 에아 유생기를 완전발생 시키는데 $25^{\circ}C$ 수온에서 최저 11일이 걸렸다. 각 유생기의 형태적 특징을 상세히 기재 및 도시하였다. 밤게의 제1조에아 유생은 갑각에 아주 짧은 액극을 가 지고 배극이 없다는 것을 제외하고는 그 외의 모든 특징에서 이미 알려진 밤게 속의 다른 유생과 잘 일치하고 있었다. 밤게가 속하고 있는 subfamily Philyrinae의 조에아 유생은 그 특징에 의거 Arcania septemspinosa, A. undecimspinosa elongata, 긴손밤게(Myra fugax)을 포함한 군과 Philyra corallicola, 납작손밤게(P. syndactyla), 밤게(P. pisum)을 포함한 군으 로 나눌 수 있다.

• Animal Systematics, Evolution and Diversity
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• 제27권1호
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• pp.47-52
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• 2011

Creeping ctenophores, Coeloplana species, were collected by SCUBA divers throughout the year (November 2006 to June 2010) from the branches and polyp masses of encrusting dendronephthyas at a depth of 20-32m off Munseom Island (Seogwipo-si, Jeju-do, Korea). A single individual of a newly recorded species in Korea, Coeloplana bocki Komai, 1920, was collected together with C. anthostella from the same location on 16 August 2009. A large number of individuals of each species were subsequently collected from the host Dendronephthya aff. dendritica on 20 June 2010. C. bocki can be distinguished from C. anthostella Song and Hwang, 2010 and C. komaii Utinomi, 1963 by its unique blue and orange colored stripes, and/or the branching and anastomosing milky-white stripes encircling the aboral sense organ towards the margin. The detailed morphology and molecular sequence information (nuclear 18S rDNA, internal transcribed spacer 1, and mitochondrial cox1 gene sequences) for C. bocki is provided, and C. bocki and C. anthostella are compared.

• Animal Systematics, Evolution and Diversity
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• 제27권2호
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• pp.159-163
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• 2011

DNA barcoding of Bryozoa or "moss animals" has hardly advanced and lacks reference sequences for correct species identification. To date only a small number of cytochrome c oxidase subunit I (COI) sequences from 82 bryozoan species have been deposited in the National Center for Biotechnology Information (NCBI) GenBank and Barcode of Life Data Systems (BOLD). We here report COI data from 53 individual samples of 29 bryozoan species collected from Korean seawater. To our knowledge this is the single largest gathering of COI barcode data of bryozoans to date. The average genetic divergence was estimated as 23.3% among species of the same genus, 25% among genera of the same family, and 1.7% at intraspecific level with a few rare exceptions having a large difference, indicating a possibility of presence of cryptic species. Our data show that COI is a very appropriate marker for species identification of bryozoans, but does not provide enough phylogenetic information at higher taxonomic ranks. Greater effort involving larger taxon sampling for the barcode analyses is needed for bryozoan taxonomy.

• Animal Systematics, Evolution and Diversity
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• 제27권2호
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• pp.151-158
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• 2011

Fish community structure in the Pyeongchanggang River was investigated from April to November 2009. About 900 individuals representing 24 species from eight families at six sites in the Pyeongchanggang River were collected. It was similar to the 2001's survey and it was less than 2006's survey. The Korean endemic species, Zacco koreanus was the most abundant, whereas subdominant species were native species, such as Pungtungia herzi, Zacco platypus, Rhynchocypris kumgangensis and Rhynchocypris oxycephalus. Three endangered species were collected at the sampling area, Acheilognathus signifier (relative abundance [RA] 0.9%), Pseudopungtungia tenuicorpa (RA 1.4%), and Cottus koreanus (RA 3.6%). One natural monument species, Hemibarbus mylodon, was included. According to the analysis of ecological indicator characteristics, the relative proportion of tolerant species was 6.3% (57 individuals), whereas the proportion of sensitive species was 65.9% (593 individuals). Species evenness, richness and diversity indices decreased gradually through the month from April to November during the study. Community indices in Pyeongchanggang River showed a high evenness index (J'>0.6), a low level of species richness (R<3.5) and a medium level of diversity (1.5

• Animal Systematics, Evolution and Diversity
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• 제28권4호
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• pp.269-278
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• 2012

Gobiids are hyperdiverse compared with other teleost groups, with about 2,000 species occurring in marine, freshwater, and blackish habitats, and they show a remarkable variety of morphologies and ecology. Testing the effectiveness of DNA barcodes on species that have emerged as a result of radiation remains a major challenge in evolutionary biology. Here, we used the cytochrome c oxidase subunit 1 (COI) sequences from 144 species of gobies and related species to evaluate the performance of distance-based DNA barcoding and to conduct a phylogenetic analysis. The average intra-genus genetic distance was considerably higher than that obtained in previous studies. Additionally, the interspecific divergence at higher taxonomic levels was not significantly different from that at the intragenus level, suggesting that congeneric gobies possess substantial interspecific sequence divergence in their COI gene. However, levels of intragenus divergence varied greatly among genera, and we do not provide sufficient evidence for using COI for cryptic species delimitation. Significantly more nucleotide changes were observed at the third codon position than that at the first and the second codons, revealing that extensive variation in COI reflects synonymous changes and little protein level variation. Despite clear signatures in several genera, the COI sequences did resolve genealogical relationships in the phylogenetic analysis well. Our results support the validity of COI barcoding for gobiid species identification, but the utilization of more gene regions will assist to offer a more robust gobiid species phylogeny.

• Animal Systematics, Evolution and Diversity
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• 제27권2호
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• pp.115-122
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• 2011

The morphology of the two marine hypotrichous ciliates Apokeronopsis bergeri and A. ovalis, isolated from the Yellow Sea, Korea, are described based on live and protargol-impregnated specimens. It is the first time that these species have been recorded in Korea. In addition, the small subunit ribosomal RNA gene was sequenced for comparison with the public database. The genus Apokeronopsis has recently been established in the family Pseudokeronopsidae, and the two congeners of the Korean population share the following characteristics: one row of one or more buccal cirri; usually two frontoterminal cirri; midventral complex composed of two distinctly separated rows; one left and one right marginal row; number of transverse cirri, more than eight; absence of caudal cirri; two types of cortical granules. Apokeronopsis bergeri differs from A. ovalis primarily in body shape (fusiform vs. oval form), size (usually $260{\times}80{\mu}m$ vs. $160{\times}55{\mu}m$), type II cortical granules (oval vs. round shape; yellow-green vs. mostly colourless and only a few yellow-green in colour), and morphometric data (75-106 vs. 53-70 in adoral membranelles; 37-47 vs. 24-36 in frontal cirri; 9-15 vs. 1-2 in buccal cirri), as well as molecular data (2.87% of pairwise distance).