Forest floor litter communities include detritivorous, predacious, and parasitic arthropods that feed on, or forage within, the decaying organic material. Although this substrate is heterogeneous, little research has investigated the preferential feeding tendencies of these arthropods. The objective of this study, conducted in the lowland rain forest of French Guiana, was to examine some of the factors that may influence foraging behavior. Plots were covered with either leaf or floral litter from three species of Lecythidaceae (Brazil nut family), and traps were set within and above each plot. Traps baited with floral litter yielded significantly more arthropods than those baited with leaf litter. Floral and leaf tissues were subsequently analyzed for moisture, fiber, sugar and nutrient concentrations. These analyses indicate that, relative to leaf litter, floral litter provides a quantitatively richer nutrient source available at lower energy expenditure, suggesting that these arthropods (mostly insects) may be operating under optimal foraging strategy.