Populations of the specialist gall-forming fly, Urophora cardui (Diptera: Tephritidae), were studied at the western and eastern margins of its distribution. In western Europe U. cardui attacks the creeping thistle Cirsium arvense, whereas in eastern Europe, in the Ural mountains, it attacks Cirsium setosum, a taxon closely related to C. arvense. Gall densities are high in the Ural mountains and can be predicted by environmental variables. Compared to galls on C. arvense, those on C. setosum are on average larger. This indicates better performance of U. cardui on C. setosum in terms of cell numbers per gall. Despite the wide distribution of U. cardui, the dominant parasitoids are the same at the western and eastern ends of its distribution and the interactions between parasitoids and the host are similar. In general, we suggest that the synchronisation between the host plant species, the phytophage and the parasitoids is an important factor in the spatial ecology and evolution of this food web.
Primers to amplify partially the mitochondrial genes coding for cytochrome b, 12S-rRNA and the D-loop were screened in twelve small mammal species from southern Africa. We also tested the possibilities of molecular sex identification using primers of the SRY. The study includes five species of murids of the genera Aethomys, Thallomys, Rhabdomys and Saccostomus, four gerbils of the genera Desmodillus, Tatera, Gerbillurus, one dormouse (Graphiurus) and two macroscelids (Macroscelides and Elephantulus). We provide information on the primers with modifications, lab protocols and we give an overview of the obtained sequences: four cytochrome b sequences and five 12S-rDNA sequences of three species and 23 D-loop sequences of five species. Sex specific fragments of SRY could be amplified in three species of Murinae and the dormouse.