采用线粒体16S rRNA、COX1和Cytb基因测定11种小丑鱼的序列,分析其基因序列差异和遗传距离关系,并用邻接法、最大似然法和贝叶斯法构建系统进化树,探讨了11种小丑鱼的系统发育关系.序列分析结果显示,经比对处理后的3个基因总长度4388 bp,其中多态位点1028个,简约信息位点616个,转换与颠换比为2.12,A+T的平均含量为54.7％,高于C+G的平均含量45.3％.系统发育关系表明:(1)双锯鱼亚科为单系发生,但双锯鱼属不为单系发生,建议对棘颊雀鲷属重新定位;在双锯鱼属中,公子小丑鱼Amphiprion ocellaris和黑边公子小丑鱼Amphiprion percula聚为一支,为双锯鱼亚科分子亲缘关系基础;(2)透红小丑鱼Premnas biaculeatus在双锯鱼属的定位较为模糊,贝叶斯树显示透红小丑鱼P.biaculeatus与公子小丑鱼A.ocellaris和黑边公子小丑鱼A.percula聚成一支并位于该支的底端,而NJ树和ML树中透红小丑鱼却没能和公子小丑鱼A.ocellaris和黑边公子小丑鱼A.percula聚为一支,而是和其他小丑鱼汇聚成一支;(3)透红小丑鱼P.biaculeatus与金透红小丑鱼Premnas epigrammata是同一种.%Sequences of mitochondrial 16S rRNA,COX1 and Cytb genes were determined to establish the phylogenetic relationship among 11 species of anemonefish using the neighbor joining (NJ),maximum-likelihood (ML) and Bayesian methods with the divergence and genetic distances determined as well.The 3 genes had a combined length of 4388 bp that consisted of 1028 polymorphic and 616 parsimonious information sites.The ratio of transition to transversion was 2.12,and the average A+T content was 54.7％,which was higher than 45.3％ for C+G in the genes.It was found that (1) the subfamily Amphiprioninae was monophyly,but the genus Am phiprion was not monophyletic,implying Premnas should be reclassified;(2) the phylogenetic trees grouped the percula complex into a clade that formed the ancestral taxon of anemonefish,but the phylogenetic relationship was uncertain in regard to Premnas biaculeatus;and,while the Bayesian tree placed the percula complex and P.biaculeatus in a same clade,NJ and ML tree classified P.biaculeatus in a clade with subgenera Amphiprion,Paramphiprion and Phalerebus;and,(3) the genetic distance between species suggested a possibility of P.biaculeatus and Premnas epigrammata being identical.
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