Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Evening Poster

M (Multidisciplinary and Interdisciplinary) » M-GI General Geosciences, Information Geosciences & Simulations

[M-GI25] Environmental changes in mountainous area

Tue. May 22, 2018 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Keisuke Suzuki(Department of Environmental Sciences, Faculty of Science, Shinshu University), Yoshihiko Kariya(Department of Environmental Geography, Senshu University), Chiyuki Narama(新潟大学理学部理学科, 共同), Akihiko SASAKI(Department of Geography and Environmental Studies, Kokushikan University)

[MGI25-P02] Effects of mountain ranges on the genetic structures of the burrowing mayflies, Ephoron (Polymitarcyidae)

★Invited Papers

*Kazuki Sekine1 (1.Faculty of Geo-Environmental Science, Rissho University)

Keywords:Phylogeography, Ephemeroptera, DNA

Adults of polymitarcyid mayflies emerge simultaneously, and often swarm in large numbers. The adult stage is extremely short (1 to 2 h). In Japan, a polymitarcyid species, Ephoron shigae is observed. The adults emerge simultaneously and often swarm in large numbers in September. Because adults show positive phototaxis, swarming around lights on bridges has been observed. In addition, the legs of female adults are so degenerate that the females can not easily take flight and may die when they fall to the ground. Therefore, dead E. shigae individuals often accumulate on the streets like snow. The mayflies are not only distributed in Japan, but also Far East Russia and Korea.

In this study, I studied the genetic structures of E. shigae populations to examine, whether the populations are fragmented by mountains. In addition, I also examined the genetic structures of E. nigridorsum which is distributed in the Mongolian Selenge River basin.

As results, although E. nigridorsum had high genetic diversity, there was little geographic cluster of haplotypes within the river basin. In addition, the genetic structure showed stable type for long time. Although Korean E. shigae did not show clear fragmentation by geographic barrier such as the Sobaek Mountains, Japanese E. shigae was divided to two groups, the Eastern and Western Japanese groups. The migration and gene flow of Japanese E. shigae would have been affected by the geological events around the Fossa Magna and the Japanese Alps.