A new species, Rhopalomyia longicauda (Diptera: Cecidomyiidae), inducing large galls on wild and cultivated Chrysanthemum (Asteraceae) in China and on Jeju Island, Korea

A gall midge (Diptera: Cecidomyiidae) that was previously misidentified as Epimyia sp. has been known as a serious pest of chrysanthemum (Asteraceae) cultivated for ornamental and medical purposes in China. Based on DNA sequencing data and morphological features, we concluded that this gall midge belongs to the genus Rhopalomyia and is identical to gall midges collected from Chrysanthemum indicum on Jeju Island, Korea and in Hubei Province, China. We describe the gall midge as a new species, Rhopalomyia longicauda, and provide details of the host range, gall shape, distribution, life history, and pest status. We also urgently warn those who are responsible for growing chrysanthemums against importing potentially infested plants into Japan or Korea (except Jeju Island).