Key-words: invasive species, interactions, intra-guild predation, survival, crayfishWe investigated potential interspecific predation between two invasive crustacean species, currently widespread and co-occurring in European inland waters: the Ponto-Caspian amphipod Dikerogammarus villosus (Gammaridae) and the North American spiny-cheek crayfish Orconectes limosus (Cambaridae). We evaluated interactions of adult specimens of D. villosus and juvenile O. limosus (from the 3rd developmental stage -DS) under conditions with and without feeding. We used two different experimental setups: short-term (one-week) rearing in aquaria each containing 30 specimens of either single-species or mixed stock, and 20-daylong rearing in small circular plates with one individual of each species.