A NEW GENUS AND 2 NEW SPECIES OF GALL MIDGE (DIPTERA, CECIDOMYIIDAE) DAMAGING YOUNG BRANCHES OF EUCALYPTUS SPP IN SOUTH AUSTRALIA

Two new gall midges are described from galls on young branches of two Eucalyptus species in South Australia and a new genus, Okriomyia, is d escribed to contain them. The new genus belongs to the tribe Asphondyl iini and the subtribe Schizomyiina. It differs from other Schizomyiina in the shape of the aedeagus, the solid tooth of the gonostylus and t he cerci-like female tenth tergite. Okriomyia schwarzi gen. et sp. nov . was found on Eucalyptus gracilis and O. flabellidentata sp. nov, on E. cosmophylla. Infested branches fracture at the site of the gall as the trees mature. Males, pupae, and larvae of both species and the fem ale of O. schwarzi are described. The new species differ from each oth er in the morphology of the male genitalia, the pupal face, and the pu pal prothoracic spiracle. A key to the Australian genera of the tribe Asphondyliini is given.