为完善中国裸胸鳝属鱼类物种信息，实验报道了采集于中国大陆沿海水域(福建省厦门市和广东省汕头市)的新记录种——鞍头裸胸鳝，目前该物种世界上仅日本及中国台湾东部有分布记录。通过对采集样品进行详细的形态学特征分析，综合利用DNA条形码COⅠ及16S rRNA基因进行分子鉴定及系统分类研究。结果显示，鞍头裸胸鳝主要鉴别特征为:体色浅褐色，眼后头顶有一个暗色马鞍状斑纹，背鳍起点前有一黑色三角形大斑块，腹部有黑色条纹从鳃孔下方延伸至肛门，背鳍、臀鳍边缘均为白色;体修长，全长为体高的19。06～19。60倍;上下颌齿均单行，上颌齿每侧8个，下颌齿12～14个，总脊椎数为162～168。基于COⅠ及16S rRNA基因分析，鞍头裸胸鳝与其他裸胸鳝遗传距离分别为CO Ⅰ(0。120～0。255)，16S rRNA(0。059～0。132)，其中 CO Ⅰ 遗传距离已远大于 Herbert 设定的2％最小物种鉴定遗传距离，揭示鞍头裸胸鳝为独立物种。进化树上，鞍头裸胸鳝与白缘裸胸鳝聚为一支，二者亲缘关系较为紧密。研究表明，鞍头裸胸鳝在中国大陆沿海也有分布，为有效新记录种。本研究为中国裸胸鳝属鱼类的系统分类及物种名录修订提供相关分类基础。
Morphological and molecular phylogenetic studies of a newly-recorded Gymnothorax species in China Sea——G.sagmacephalus
Genus Gymnothorax is one of the most diverse,abundant and widely distributed genera of moray eels in the family Muraenidae;there were more than 100 valid species of Gymnothorax all over the world and approxim-ately 20-30 species recorded in China.It was a poorly known group in China,with very few studies focusing on it.To improve the species list information of the Gymnothorax resource,this study reported a newly-recorded spe-cies,G.sagmacephalus Böhlke,1997,which was previously only recorded in Japan and eastern Taiwan,China.Two individuals of the species were collected from the coastal area of Xiamen City,Fujian Province and Shantou City,Guangdong Province.The detailed morphological characteristics of the new species were described,and the molecular identification as well as phylogenetic construction were preformed based on DNA barcoding CO Ⅰ gene and 16S rRNA gene.The result showed that,the diagnostic characters of G.sagmacephalus were:body coloration light brown,a dusky saddle-like marking on the top of head just behind eyes,and a large prominent dark triangle marking just before the dorsal-fin origin;black stripes on the abdomen extending from the gill opening to the anus;dorsal and anal fins with a white margin;body was elongate,total lengths were 19.06-19.60 times of body height;teeth were uniserial,and maxillary teeth with 8 on each side without additional inner row teeth;number of dentary teeth were 12-14;total vertebrae were 162-168.Based on the analysis of CO Ⅰ and 16S rRNA gene,the genetic distance between G.sagmacephalus and related Gymnothorax species with pure body color were:CO Ⅰ(0.120-0.255);16S rRNA(0.059-0.132).The genetic value of CO Ⅰ were greater than the 2％minimum diagnostic threshold suggested by Herbert,indicating that G.sagmacephalus was an independent species.The molecular phylogenetic tree showed that G.sagmacephalus and G.albimarginatus were tightly clustered as one group,indic-ating their close relationship.The results clarified that G.sagmacephalus was a newly recorded species and could be found in the coastal water of mainland China,which also provides a taxonomic basis for the systematic classi-fication and the species list revision of the Gymnothorax fish in China.
Gymnothorax sagmacephalusnewly recorded speciesmorphological characteristicsCO Ⅰ gene16S rRNA gene
万方数据
