한국과 중국의 근해에서 서식하는 부유성 요각류 Paracalanus parvus sensu lato (Calanoida: Copepoda) 의 유전적 다양성

Abstract

Paracalanus parvus sensu lato (P. parvus s. l.) is a cosmopolitan small copepod species, and dominates in the world ocean. Especially In the coastal waters of the yellow sea it plays an important role in zooplankton community. However this species should be separated and there is an urgent need for taxonomical reexamination. Currently the species identification is a laborious task involving the extensive use of microscope and may result in erroneous assignment. Thus, the analysis of DNA sequences became the most accurate technique allowing detection of genetic diversity at molecular level. The mitochondrial COI gene (mtCOI) study was sequenced from on 120 individuals of Paracalanus parvus s. l. collected from the coastal waters of Korea and China, including the Baekdo (Korea), Incheon (Korea), Pohang Port (Korea), and Qingdao (China). A homologous 618 bp region of the mitochondrial COI gene (mtCOI) was examined and statistically analyzed for the four populations. For each individual copepod, the DNA sequence was determined for a 618-bp region of the mtCOI gene. A total of 18 different mtCOI sequences, or haplotypes, were detected. The analysis of haplotypes types reveals that H1, H2 and H5 more frequent than the other types among all the eighteen types and that all of the four populations comprise these three haplotypes. The Baekdo population has the most numerous haplotypes (10) and the polymorphic (segregating) sites (15). Haplotype minimum spaning networks, nucleotide divergence and Fst values indicated that individuals from the three Korean coastal sites were more closely related compare with the population collected in the Chinese Qingdao site. This work also indicates that the P. parvus s. l. in the coastal waters of Korea and China are the same species, although the P. parvus s. l. in the coastal waters of Okinawa, Japan is an another species.