Radiation of gall midges (Diptera: Cecidomyiidae) in Japan

Abstract

Summary Based on literature surveys and morphological and DNA sequencing data, we examined patterns of host association at the generic level for the Japanese gall midges. Many examples of association of a gall midge genus with a particular host plant genus are known. We found that associations exist between Rabdophaga and Salix, Hartigiola and Fagus , Rhopalomyia and Artemisia, and Daphnephila and Machilus , whereas the host range of some large genera, such as Asphondylia , Contarinia , Dasineura , and Lasioptera spans different plant families. Most Rabdophaga and some Rhopalomyia species seem to have colonized the Japanese Archipelago after radiation in the Eurasian Continent. Daphnephila came to Japan from the Oriental Region where they radiated on Machilus . Most Fagus gall midges seem to have diversified on relic Fagus species in the eastern Palearctic Region. Some Hartigiola species appear to have radiated in the Japanese Archipelago. Although Asphondylia has a wide host range at the generic level, most Japanese Asphondylia species and segregates are close to each other genetically, which means they are now spreading to various plant genera.