中国南方沿海13种石斑鱼类的分子系统进化关系分析

摘要

石斑鱼类（Groupers）是世界性海洋经济鱼类，也是中国南方沿海省份重要的海水增养殖对象，其种类繁多，由于缺乏明显的种间外部形态区别特征，石斑鱼的分类一直是鱼类系统分类学的一个难题，存在着较多的争议和混淆。为了从分子水平揭示石斑鱼类的系统进化关系，应用线粒体细胞色素b基因（ Cyt b ）及两个核糖体RNA基因（16S和12S）序列联合构建系统进化树对中国近海石斑鱼亚科3属13种进行种类鉴定及亲缘关系分析，探讨了石斑鱼类的分子系统进化。结果表明：①线粒体基因序列在石斑鱼类种间存在较大的变异，种内变异极小，是进行石斑鱼类种类鉴定较为适宜的分子标记；②所研究的3属13种石斑鱼类中，石斑鱼属与九棘鲈属的亲缘关系较近，与鳃棘鲈属的较远；③赤点石斑鱼和青石斑鱼、蜂巢石斑鱼与鮭点石斑鱼、斜带石斑鱼与棕斑石斑鱼两两间具有较近的亲缘关系。%The groupers are commercially important marine species over the world , and they are also the important mariculture species of the coastal provinces in south China .The great variety of the species and the lack of morphological characteristics led to much confusion and dispution in their phylogenetic rela-tionships and species identification .In the present study , we try to reveal the phylogenetic relationships of groupers on molecular level .The partial mitochondrial cytochrome b ( Cyt b ) gene and two ribosomal genes (16S and 12S) were combined and applied to species identification and relationship analysis of 13 Epinepheline species from 3 genera distributed in coastal waters of south China .The results showed that:①The mitochondrial genes are appropriate as molecular markers for Epinepheline species identification because considerably high sequence difference among species and very low within species were found in these 3 genera;② Epinephelus was more closely related to Cephalopholis than to Plectropomus; ③ The genetic relationship was very close between E.akaara and E.awoara, E.merra and E.longispinis, E.coioides and E.corallicola.