Tree litter identity and predator density control prey and predator demographic parameters in a Mediterranean litter-based multi-trophic system

•Litter identity and predator density regulate tri-trophic interactions (Fungi - fungivorous Collembola - predatory Acari) in forest ecosystems.•Pine litter favors fungi and Acari whereas oak litter favors Collembola.•High predator density negatively affects both Collembola and Acari demographic parameters.