中国近海带鱼Trichiurus japonicus的命名和分类学地位研究

Study on the Nomenclature and Taxonomic Status of Hairtail Trichiurus japnocus from the Chinese Coastal Waters

带鱼属（Trichiurus）鱼类是中国最重要的海洋渔业捕捞对象之一。然而,有关中国南北沿海均有分布的这种带鱼（简称中国近海带鱼）应取何名、属于何种及其系统进化过程等问题仍未有统一的认识和定论。本研究通过测定中国近海带鱼14个群体共计166个个体的线粒体16S r RNA基因序列,分析该物种与中国近海其他3种带鱼属鱼类的序列变异,比较该种带鱼与世界其他带鱼属有效种的形态差异,综合探讨其命名、分类地位及系统进化过程。基于Kimura双参数模型计算,中国近海带鱼（Tsp-CH）与台湾（Tj-WT）及日本（Tj-JP）的带鱼（Trichiurus japonicus）的组间净遗传距离（0.000 7-0.002 1）远低于带鱼属内其他种间的净遗传距离（0.065 6-0.082 0）,也明显低于高鳍带鱼（Trichiurus lepturus）地理群体间的遗传距离（0.010-0.016）;分子变异分析（AMOVA）和FST分析均表明这三组带鱼组间遗传分化不显著。结果表明,中国近海带鱼与来自台湾及日本的带鱼（T.japonicus）的遗传分化处于种内水平。采用邻接法构建的分子系统树显示,不同地理来源的带鱼（T.japonicus）（即包括Tsp-CH,Tj-WT,Tj-JP）与高鳍带鱼（T.lepturus）、南海带鱼（Trichiurus nanhaiensis）、短带鱼（Trichiurus brevis）等3种带鱼属鱼类互为单系,在属内各自形成独立的进化分支。结合分子数据和形态学比较研究资料,本研究确认中国南北沿海均有分布的这种带鱼是Trichiurus japonicus Temminck et Schlegel,1844,它在种的分化、形成、分布及形态上与世界其他带鱼属鱼类存在系列差异。

The hairtail fishes（Trichiuridae： Trichiurus） are one of the most important marine fishery targets in China.However, there is still no unified understanding and conclusion on the nomenclature, taxonomic status and phylogenetic process of the hairtail fish which distributed along the coast of north and south of China（referred as Chinese Trichiurus sp.）. In this research, we sequenced the mitochondrial 16 S r RNA gene fragment of 166 individuals of Chinese Trichiurus sp. which were collected from 14 geographic locations, and analyzed the sequence variations between this species and the other 3 Trichiurus species in the coastal waters of China. Moreover, the morphological differences between the Chinese Trichiurus sp. and the other valid species of genus Trichiurus in the world were also compared in this study. The nomenclature, taxonomic status and phylogenetic process were discussed.Based on Kimura-2 parameter calculation, the net genetic distance among Chinese Trichiurus sp.（Tsp-CH group）,Trichiurus japonicus from Taiwan（Tj-WT group）, and T. japonicus from Japan（Tj-JP group） were ranged from 0.000 7 to 0.002 1. These values were much lower than those found in some interspecific distance of genus Trichiurus（0.065 6 -0.082 0） and significantly lower than that among the geographical populations of Trichiurus lepturus（0.010-0.016）. Both AMOVA and FSTanalysis showed that there was no significant genetic differentiation among the three groups of Trichiurus. These results indicated that the genetic differentiation between Chinese Trichiurus sp., T. japonicus from Taiwan and Japan were at the intraspecific level. The phylogenic neighbor-joining analysis showed that the Trichiurus from different geographical sources and 3 species of genus Trichiurus： T. japonicus（including Tsp-CH, Tj-WT, Tj-JP）, T. lepturus, Trichiurus nanhaiensis and Trichiurus brevis, were monophyletic of each other, and formed an independent evolutionary branch within the genus. In combination with molecular results and morphological comparative data, we would confirm that the species of Chinese Trichiurus sp. should be considered as Trichiurus japonicus Temminck and Schlegel, 1844. Its differentiation, formation, distribution and morphology might be different from those of other genus Trichiurus in the world.