Lixus cribricollis [Col.: Curculionidae] for biological control of the weedsEmex spp. andRumex crispus in Australia

The biology and host specificity of a colony ofLixus cribricollis Boheman originating in Morocco were studied in quarantine in Australia.L. cribricollis adults are long lived, have an aestivation and are univoltine.Rumex crispus L.,Emex australis Steinheil andE. spinosa (L.)Campdera were shown to be the only satisfactory hosts of 40 species of plants from 17 families that were exposed to sexually mature adults ofL. cribricollis. Normal feeding and occasional oviposition were observed on some other plants within the same family,Polygonaceae, including the minor crops rhubarb and buckwheat, but almost invariably larvae died in the 1st instar. It was concluded thatL. cribricollis may be a useful biological control agent for the weedsR. crispus, E. australis andE. spinosa and that establishment of this weevil in Australia would be without risk to non-target plants.