Catalogue of parasitoids and inquilines in cynipid oak galls in the West Palaearctic.

Abstract

A quantitative catalogue of the parasitoids (almost exclusively Chalcidoidea) and inquiline Cynipidae recorded in the western Palaearctic from galls induced on Quercus by Cynipidae (Cynipini) is presented. Quantitative and national data are included with bibliographic references to almost all records published in 2011 and earlier. The catalogue is followed by two checklists, firstly one of the Chalcidoidea with numbers of each species recorded from each type of host gall (galls of the sexual and asexual generations of the host gall wasps are listed separately), and secondly one of inquiline Cynipidae with host galls. Compared to non-oak gall wasps, the Cynipini support a much larger parasitoid and especially inquiline fauna, and this fauna is very largely restricted at the species level to Cynipini galls. About one hundred chalcidoid species are recorded from galls of Cynipini, distributed over six families: Pteromalidae and Eulophidae (29 species each), Torymi-dae (21 species), Eurytomidae (10 species), Eupelmidae (8 species) and Ormyridae (at least 2 species). Polyphagy is usual in the chalcidoid parasitoids, most species having a broad host gall range, but quantitatively the fauna of each type of oak gall is rather characteristic and is strongly influenced by gall morphology, situation on the tree, season of growth and host tree species. These and other extrinsic factors restrict the full exploitation of the chalcidoids' potential host gall range.