Open Access

Werner Hanagarth, Martin Brändle

• The beetle fauna of soil and litter in Amazon forest eco-systems was studied by means of Berlese-Tullgren extractions, at 8 sampling dates during 2 years in four experimental plots (one in primary forest, one in secondary forest and two polyculture plots) of the Embrapa Amazonia Ocidental research centre near Manaus (Brazil). Beetle individuals were found in 99 % of the extracted litter and soil cores. In total, we recorded 47 beetle families, of which 12 contributed to more than 90% of the total individual numbers and beetle biomass, respectively. Most individuals recorded were very small averaging less than 2 mm body length. The total number of predator families was low (6 families, 13 %), when compared to that of the decomposers (29 families, 62 %). Only one family was considered herbivorous (Chrysomelidae, 2 %). 28 % of the decomposer families, but 67 % of the predator families ranged among the 12 most abundant beetle families. Among the 12 dominant beetle families the carnivorous Scydmaenidae, Staphylinidae, Carabidae and Pselaphidae represented 51 % of the abundance and 41 % of the biomass. In comparison to other macroarthropods (Chilopoda, Formicidae, Isoptera, Diplopoda) the contribution of Coleoptera to the total of individual numbers or faunal biomass was rather small. We conclude that although diversity of the soil dwelling beetles seems to be high, their total contribution to nutrient cycling may be of minor importance.