Evolutonary and phylogenetic study on the Drosophila virilis section (Diptera : Drosophilidae)

对覆盖亚热带和寒温带的日本群岛的果蝇区系进行了调查，并对繁殖底物、微生境和季节波动进行了生态调查。对日本果蝇区系进行了核型分析、生殖隔离研究、ADH基因和线粒体DNA分析。分子系统树分析表明，罗布斯塔种群是一个多系统群，由冈田亚组、乳齿亚组和罗布斯塔亚组组成。这一结论得到了核型观察的支持。冈田组和四分组建立了相同的集群，而罗布斯塔亚组和黑色素组则建立了另一个集群。在此基础上，讨论了生殖器段的进化过程。

Faunal surveys of the Drosophila virilis section were made in the Japan Islands covering subtropical regions to cool temperate regions, together with ecological surveys on breeding substrates, microhabitats and seasonal fluctuations. Two new species, 3 newly recorded species and several insular subspecies were added to the Japanese fauna of drosophilidsKaryotype analyzes, reproductive isolation studies, analyzes of Adh genes and mtDNA were carried out by using Japanese members of the virilis section and their related foreign species. The molecular phylogenetic tree demonstrated that the robusta species-group was polyphyletic, comprising the okadai subgroup, the lacertosa subgroup and the robusta subgroup. This was supported by the karyotype observation. The okadai subgroup and the quadrisetata group built the same cluster, whereas the robusta subgroup and the melanica group did another cluster. The evolutionary process of the virilis section was discussed based on the results obtained.