中国北方常见芫菁分子物种界定(鞘翅目:芫菁科)

Molecular species definition of common blister beetles(Coleoptera:Meloidae)from northern China

【目的】应用线粒体COI和核CAD基因片段探讨自动条形码间隔探索(automatic barcode gap discovery,ABGD)、广义混合Yule溯祖模型(generalized mixed Yule coalescent,GMYC)、贝叶斯泊松树进程(Bayesian Poisson tree processes,bPTP)和贝叶斯系统发育和系统地理分析(Bayesian phylogenetics and phylogeography,BPP)4种分析方法在芫菁科(Meloidae)昆虫分子物种界定中的适用性。【方法】分别基于COI,CAD和COI+CAD串联序列数据集,应用ABGD,GMYC,bPTP和BPP 4种方法对中国北方芫菁科常见的6属(沟芫菁属Hycleus、斑芫菁属Mylabris、豆芫菁属Epicauta、绿芫菁属Lytta、星芫菁属Megatrachelus和短翅芫菁属Meloe)18个形态种进行分子物种界定,并与形态学鉴定结果进行比较。【结果】利用COI+CAD串联序列数据集所得物种界定结果与形态鉴定结果一致;COI数据集使用ABGD和GMYC方法的界定结果与形态鉴定结果一致,而bPTP划分的物种数较形态鉴定结果多;基于CAD序列在3种单基因物种界定方法的结果中,除GMYC与形态划分一致外,其余均显示部分结果与形态划分不同。【结论】在芫菁科分子物种界定中,多基因联合序列、多种界定方法分析所得结果优于单一基因片段和界定方法的分析结果。本研究的结果为芫菁科昆虫的分子物种界定和整合分类提供了数据支持和参考。

【Aim】This study aims to test the applicability of four analytical methods,including automatic barcode gap discovery(ABGD),generalized mixed Yule coalescent(GMYC),Bayesian Poisson tree processes(bPTP),and Bayesian phylogenetics and phylogeography(BPP)with fragments of two genes,mitochondrial COI and nuclear CAD,in the molecular species definition of Meloidae insects.【Methods】Eighteen meloid morphologic species widely distributed in northern China and belonging to six genera(Hycleus,Mylabris,Epicauta,Lytta,Megatrachelus,and Meloe)were sampled.The molecular species definition was carried out based on COI,CAD,and concatenated COI+CAD sequence data sets by using ABGD,GMYC,bPTP,and BPP.The molecular species definition results by using different methods were compared with that by the morphological identification,respectively.【Results】The molecular species definitions based on the COI+CAD concatenated sequence data sets were consistent with the morphological identification results,those based on COI sequences with the ABGD and GMYC methods were also consistent with the morphological identification results,while the number of species identified by using bPTP was more than that by morphological identification.The definition results based on CAD sequences by using all three single-gene species definition methods except GMYC were partially different from the morphological identification results.【Conclusion】The molecular species definitions of Meloidae based on multi-gene concatenated sequences and multiple methods are better than those based on single gene fragment or single definition method.The results of this study provide data support and reference for molecular species definition and integrative taxonomy of the family Meloidae.