Species richness of associates of ants in the nests of red wood ant Formica polyctena (Hymenoptera, Formicidae)

1. Ant nests are rich with various other fauna, and they may be seen as resources for these guest species. We studied the species richness and abundance of ant guests in the nests of Formica polyctena by addressing the resource concentration hypothesis, which predicts that nests in high densities would support higher species richness and abundance of specialised guests. 2. In 12 nests we found 1562 individuals belonging to 70 taxa, of which beetles were the most species rich group. The resource concentration hypothesis was supported, as we found the species richness to be higher in nests with close neighbours. There was no relationship between the abundance of associates and the nearest neighbour distance. 3. Non-parametric methods were applied for total species richness estimation. These suggest that additional sampling would yield more associate species. 4. In addition, we studied the similarity of the species composition in the nests and how the distance between the nests correlates with it. Overall, nests from the same area appeared to be most similar with each other. A significant negative trend between geographical distance and similarity of the species composition was found when all species and non-myrmecophiles were tested. 5. For maintaining and conserving high arthropod diversity in temperate and boreal forests, forest management practices preserving dense red wood ant populations should be used if the habitat cannot be protected.