AbstractWe investigated the species composition and distribution of the scarab beetle (Coleoptera: Scarabaeoidea) community in Dongling Mountain (39°48′～40°02′ N, 115°24′～115°36′ E), 114 km to the west of Beijing. Three sites containing 11 plots were selected to reflect the effect of vegetation, elevation and human disturbance on scarab beetle communities. During the growing seasons of 1998 to 2000, a total of 1721 scarab beetles were captured. Six genera and 20 species of saprophages and 20 genera and 26 species of phytophages accounted for 89.2% and 10.8% of total beetle specimens, respectively. Principal component analysis (PCA) and cluster analysis were used to analyze the phytophagous and saprophagous scarab species. Similar results were obtained: the 11 plots were grouped into three categories: the shrubs at low elevation (Liyuanling), forests at low elevation (forests in Xiaolongmen and coppices Liyuanling), and alpine vegetation (the top of Dongling Mountain). This indicates that vegetation and elevation may be important factors that influence the distribution of scarab beetles in Dongling Mountain. Species diversity ( H′), species richness ( S ) and number of individuals were computed for the three categories: all were highest in shrubs and the lowest in alpine vegetation. Species evenness ( J ) of the three categories showed a complicated patterns of variation: for the saprophagous assemblage, the highest value was observed in forests and the lowest one in alpine vegetation; for the phytophagous assemblage, the highest value was in alpine vegetation and the lowest was in shrubs. The co-occurrence between common species was analyzed. For saprophagous species, Caccobius sibiricus was positively correlated to Liatongus phanaeoides and Onthophagus sp1., but all of them were negatively correlated to Onthophagus sinicus. For phytophagous species, Serica orientalis and Brahmina faldermanni showed a significantly positive correlation, and Trichoserica heydeni, Trichoserica heydeni and Clinterocera mandarina were another positively correlated group. Positive or negative correlations between these species were consistent with their abundance in the different habitats and reflect similarities and differences in their habitat preferences.