ARS | Publication request: Parasitoids (Hymenoptera: Chalcidoidea) of the Cabbage Seedpod Weevil (Coleoptera: Curculionidae) in Georgia

Submitted to: Journal of Hymenoptera Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 24, 2006
Publication Date: October 20, 2006
Citation: Gibson, G.A., Gates, M.W., Buntin, G.D. 2006. Parasitoids (Hymenoptera: Chalcidoidea) of the Cabbage Seedpod Weevil (Coleoptera: Curculionidae) in Georgia. Journal of Hymenoptera Research. 15(2):187-207.

Interpretive Summary: Invasive agricultural pests can be potentially devastating in their non-native ranges. The cabbage seedpod weevil, introduced from Europe into North America over 70 years ago, causes significant yield losses in commercial canola and rapeseed crops. This translates into millions of dollars in economic losses each year. Small native and introduced parasitic wasps can provide control of this weevil, directly reducing its populations. This paper reports on the parasitic wasps recovered from the weevil in Georgia and provides a key to identify them. This information will be useful to biocontrol workers, extension agents, scientists and regulatory agencies.

Technical Abstract: Five families and 13 species of Chalcidoidea (Hymenoptera) were reared from the seedpods of Brassica napus L. (Brassicaceae) as putative parasitoids of the cabbage seedpod weevil, Ceutorhyncus obstrictus Marsham (Coleoptera: Curculionidae), in Georgia, United States. The species are Conura torvina (Cresson) (Chalcididae), Euderus glaucus Yoshimoto and Necremnus tidius (Walker) (Eulophidae), Brasema allynii (French) n. comb. and Eupelmus cyaniceps Ashmead (Eupelmidae), Eurytoma tylodermatis Ashmead (Eurytomidae), and Lyrcus incertus (Ashmead), L. maculatus (Gahan), L. perdubius (Girault), Mesopolobus moryoides Gibson, Neocatolaccus tylodermae (Ashmead), Pteromalus cerealellae (Ashmead) and Pteromalus sp. (Pteromalidae). Ceutorhyncus obstrictus represents a new host record for B. allynii, Euderus glaucus, Eupelmus cyaniceps, Eurytoma tylodermatis, L. incertus, N. tylodermae, Pteromalus sp. and P. cerealellae. Lyrcus maculatus comprised about 86% and all the Pteromalidae about 96% of the parasitoid fauna. The only previous report of a parasitoid of C. obstrictus in eastern North America, Trichomalus perfectus (Walker) (Pteromalidae), is erroneous because of misidentification. An illustrated key is provided to differentiate the taxa and the species are discussed relative to the known parasitoid fauna of C. obstrictus in western North America.