북서태평양과 남대서양산 앨퉁이류의 유전적 유사성에 관하여

Abstract

An analysis of the 524 nucleotide long segment in the 16SrDNA mitochondrial gene of Maurolicus japonicus revealed that there are two major haplotypes (E and H) and two minor haplotypes (I and J) which comprise 63.6%, 27.2%, 4.6% and 4.6% of the population, respectively. The nucleotide sequence of the major haplotype E is completely identical to that of the most common haplotype in M. walvisensis (63.6% of the population). The other haplotypes of M. japonicus also show almost identical sequences as that of the haplotype E with only a single (haplotypes I and J) or three nucleotide differences (haplotype H). Phylogenetic trees of all the 16SrDNA haplotypes found in the Maurolicus taxa until now show that the relationships among the haplotypes of M. japonicus and M. walvisensis are indistinguishable but that they are clearly distinctive from those of M. muelleri. Examination of the morphometric characteristics of specimens reveals similarities among the individuals of different haplotypes of M. japonicus and also between M. japonicus and M. walvisensis in almost all characteristics. The results suggest that despite the current ocean-wide allopatric distribution between M. japonicus and M. walvisensis, the two taxa are conspecific as M. japonicus Ishikawa 1915.