OCCURRENCE OF TWO GALL WASPS OF THE GENUS DIPLOLEPIS (HYMENOPTERA: CYNIPIDAE) ON THE DOMESTIC SHRUB ROSE, ROSA RUGOSA THUNB. (ROSACEAE)

Abstract

AbstractStem galls of Diplolepis spinosa (Ashmead), usually found on the endemic rose Rosa blanda Ait., and root galls of D. radicum (Osten Sacken), usually found on the endemic rose R. acicularis Lindl., have become established on the cultivated rose R. rugosa Thunb. in Canada. Adults and galls of D. spinosa and D. radicum are described and compared with those of closely related species. Host records, damage, and distribution of both species are discussed as is the suitability of R. rugosa as a host. It is suggested that galls in urban habitats are being established by adults flying into cities from surrounding patches of endemic roses.