Abundance, not diversity, of host beetle communities determines abundance and diversity of parasitoids in deadwood

Ambient and substrate energy influence decomposer diversity differentially across trophic levels

The species-energy hypothesis predicts increasing biodiversity with increasing energy in ecosystems. Proxies for energy availability are often grouped into ambient energy (i.e., solar radiation) and substrate energy (i.e., non-structural carbohydrates or nutritional content). The relative importance of substrate energy is thought to decrease with increasing trophic level from primary consumers to predators, with reciprocal effects of ambient energy. Yet, empirical tests are lacking. We compiled data on 332,557 deadwood-inhabiting beetles of 901 species reared from wood of 49 tree species across Europe. Using host-phylogeny-controlled models, we show that the relative importance of substrate energy versus ambient energy decreases with increasing trophic levels: the diversity of zoophagous and mycetophagous beetles was determined by ambient energy, while non-structural carbohydrate content in woody tissues determined that of xylophagous beetles. Our study thus overall supports the species-energy hypothesis and specifies that the relative importance of ambient temperature increases with increasing trophic level with opposite effects for substrate energy.

Critical checklist of the Chalcidoidea and Mymarommatoidea (Insecta, Hymenoptera) of Germany

Background

Since the first checklist of German Chalcidoidea and Mymarommatoidea was published over two decades ago, a revision of the status of these superfamilies in Germany is overdue. The previous list contained chalcidoid species mentioned in published papers up to 2000 and was cross-checked with the data compiled by Noyes in the Universal Chalcidoidea Database. Additional species, determined by the first author, were also included. Since then, revisions of several chalcidoid genera have been published synonymising species or describing new species. The previous checklist also contained several erroneous names and doubtful records that turned out to be incorrect placements or questionable citations and are corrected in the present version.

New information

The updated critical checklist of German Chalcidoidea includes 1,610 species from 19 families.