미토콘드리아 COI gene과 16S rDNA 염기서열을 이용한 Trichiurus lepturus와 Trichiurus japonicus의 종 구별

Abstract

The family Trichiuridae comprises 10 genera and 43 species and most of the species are distributed in the tropical to the warm temperate waters. The taxonomic classification of members of the genus Trichiurus is in confusion because of their morphological characteristics such as the body shape and coloration. Especially differentiation between T. japonicus and T. lepturus is still controversial. Fishbase synonymized T. japonicus with T. lepturus, but Anirban(2007) separated the former from the later as a distinct species. In this study, we analyzed partial sequences of the mitochondrial COI gene(700bp) and 16S rDNA gene(550bp) from individuals belonging to T. japonicus and T. lepturus in order to examine the validity of T. japonicus as a separate species. The intraspecies variations of the COI gene were 0.1% to 3.5% in T. japonicus(8 samples) and at most 0.3% in T. lepturus(12 samples), whereas the interspecies variations were as much as at 10.3% to 13.3%. In the 16S rDNA gene, variations within the species turned out to be 0.1% to 0.7% in T. japonicus(15samples) and approximately 1.1% in T. lepturus(7 samples), while interspecies variations ranged from 3.4% to 4.8%. These results suggest that T. japonicus be a valid species separate from T. lepturus