Insect Biodiversity in a Prealpine Suburban Hilly Area in Italy

Human activities and habitat fragmentation are known to greatly influence biodiversity. The aim of this study was to update an entomological checklist of a prealpine area in Italy, and also to evaluate the influence of different habitats and the proximity to cities on the entomological fauna. This study included different areas of a local park in Northern Italy, covering about 4000 ha, and situated at altitudes between 190 and 960 m asl. The surveys were carried out between 2010 and 2013 using different monitoring techniques (pitfall traps, car mounted nets, light traps, direct catches on soil and vegetation, visual sampling, gall collection). Furthermore, to assess the effect of habitat and locality on the composition of epigeic beetles, pitfall traps were set and inspected from April to September. All captured specimens were classified to species level. A total of 409 species were recorded, belonging to 7 orders and 78 families. A total of 76.1% were represented by Coleoptera, 13% Lepidoptera, 9.4% Hymenoptera, followed by other orders. In particular, some species with peculiar characteristics, or whose presence in the area had not been previously reported, were detected, such as Atheta pseudoelongatula, Ocypus rhaeticus, Tasgius tricinctus, Euplagia quadripunctaria, Scotopteryx angularia, Elachista constitella, Parornix bifurca, Oegoconia huemeri, and Lasius (Lasius) alienus. It seems possible that the habitat affected the community more than the locality. The woods showed a reduced biodiversity, and a simplified community structure. The comparison of the same habitats in different localities did not show significant differences.