Concordance between molecular biogeography of Dipteromimus tipuliformis and geological history in the local fine scale (Ephemeroptera, Dipteromimidae).

Species distribution area is determined by both biotic and abiotic factors. In particular, significant geological events influence the biodiversity and the genetic structures of the organisms inhabiting the area. The establishment of physical barriers (e.g., mountains, rivers), drives species differentiation by their interference with biological dispersal or gene flow. The Japanese Islands have a high degree of biodiversity. This study focused on the Kii Peninsula, which stands out as a region of exhibiting particularly high biodiversity, and also exceptionally high endemism. The Kii Peninsula has experienced active mountain formation ever since the Quaternary period. In this study, we investigate the influence of geological events on the establishment of genetic diversity. We focused on the mayfly, Dipteromimus tipuliformis. Phylogenetic analyses were performed utilizing the mitochondrial DNA 16S rRNA and COI regions, and the nuclear DNA histone H3, PEPCK and 28S rRNA regions. As a result, it was shown that this mayfly exhibits a genetic structure that strongly reflects the geological history of the Kii Peninsula, and detected their dispersal process across the Median Tectonic Line. This is a unique and significant study, in that it clearly shows the relationship between the phylogenetic evolution of this mayfly and the corresponding geological history in surprisingly geographic fine scale.