A critical evaluation of host ranges of parasitoids of the subtribe Diabroticina (Coleoptera: Chrysomelidae: Galerucinae: Luperini) using field and laboratory host records

The subtribe Diabroticina is a large group of New World Chrysomelidae that includes corn rootworms, cucumber beetles and other pests. Recent introductions of Diabrotica virgifera virgifera LeConte into Europe, and the development of resistances to current management practices of rootworms in the USA have increased interest in new sustainable options for managing those pests. The only parasitoids that have been shown to consistently target and develop inside the beetle adults are Centistes gasseni Shaw, Centistes diabroticae Gahan (both Hym.: Braconidae), and Celatoria diabroticae Shimer, Celatoria compressa (Wulp), Celatoria bosqi Blanchard, and Celatoria setosa Coquillett (all Diptera: Tachinidae). This review improves our understanding of the realised and potential host range of these known parasitoids by rectifying erroneous references in light of new host records and from laboratory host range tests. Based on this critical review, all tachinid and braconid species studied are considered to be specific at least to the level of subtribe, i.e. Diabroticina. Celatoria setosa, Celatoria diabroticae and C. bosqi, have a narrow realized and potential host range; the former is restricted to the genus Acalymma and the last two to the fucata and virgifera groups of the genus Diabrotica. The braconids Centistes gasseni and C. diabroticae are also specific. The realized host range of C. gasseni includes species in the Diabrotica fucata and virgifera groups; while its potential host range also includes Acalymma species. The realized and potential host range of Centistes diabroticae includes Acalymma species as well as species in the fucata and virgifera groups of Diabrotica. Celatoria compressa has the broadest realised range compared to the other species studied, since it was obtained from species in several genera of Diabroticina; and its potential host range may also include Old World Aulacophora species.