本研究选取矛茧蜂亚科Doryctinae(昆虫纲Insecta:膜翅目Hymenoptera:茧蜂科Braconidae)的6族15属18种做内群,茧蜂科其它7亚科11属11种做外群,首次结合同源核糖体28S rDNA D2基因序列片段和100个形态学和解剖学特征对该亚科进行了系统发育学研究。利用“非圆口类”的小腹茧蜂亚科Microgastrinae为根,以PAUP’4.0和MrBayes3.0B4软件分别应用最大简约法(MP)和贝叶斯法对矛茧蜂亚科的分子数据和分子数据与非分子数据的结合体进行了运算分析;并以PAUP’4.0对矛茧蜂亚科的28SrDNAD2基因序列片段的碱基组成与碱基替代情况进行了分析。结果表明:矛茧蜂亚科的28SrDNAD2基因序列片段的GC含量在39.33%~48.28%之间变动,而对于碱基替代情况来讲,矛茧蜂亚科各成员间序列变异位点上颠换(transversion)大于转换(transition)。不同的分析算法所产生的系统发育树都表明矛茧蜂亚科是一个界限分明的单系群;在矛茧蜂亚科内,除了吉丁茧蜂族Siragrini为单系群外,其他族(矛茧蜂族Doryctini和方头茧蜂族Hecabolini)都是并系群。对于矛茧蜂亚科内各属之间的相互亲缘关系,不同算法所得的系统发育树的拓扑结构不完全一致,表明矛茧蜂亚科内(属及族)的系统发育关系还有待于进一步研究。
This study is the first attempt to combine gene sequences with morphological characters to provide a phylogenetic reconstruction of the subfamily Doryctinae (Insecta: Hymenoptera: Braconidae ). Eighteen species belonging to 6 tribes 15 genera of the subfamily were involved, and 11 species of 11 genera belonging to 7 subfamilies of Braconidae were used as outgroups with Microgasterinae ( Cotesia flavipes ) used as "root" to testify the monophyletic nature of the subfamily. The DNA sequences of D2 region of 28S ribosomal DNA were downloaded from the GenBank. One hundred characters of morphology and anatomy were selected and analyzed in a cladistic manner for this study. The evolutionary relationships were investigated by comparing the results from molecular data alone or molecular data combined morphological characters, using two different analysis methods: maximum parsimony (MP) by PAUP^* 4.0 and Bayesian inference by MrBayes 3.0B4. Base composition and ti/tv of 28S rDNA D2 regions were analyzed by PAUP^* 4.0. The results showed that GC content of the 28S rDNA D2 gene sequences of subfamily Doryctinae ranged from 39.33% to 48.28%. Transversion frequency of sequence variable sites among species of Doryctinae was higher than that of transition. The subfamily Doryctinae was proved to be a well-defined naturally monophyletic group; within the subfamily, evidences were found to support that only tribe Siragrini was monophyletic group, and the other tribes, tribe Doryctini and tribe Hecabolini, were paraphyletic groups. There was no consistency between the topologies of phylogenetic trees generated by different analysis methods with different data, in accordance with the results of morphological and biological research of the subfamily, suggesting that more work should be done to resolve the phylogenetic relationships among genera and tribes of the subfamily Doryctinae.