The branchiuran parasite Argulus japonicus (Crustacea, Branchiura, Argulidae) was collected from the body surface of Amur catfish Silurus asotus reared in an aquarium. These results represent the second record of A. japonicus infection in S. asotus. This is also the first record of A. japonicus infection in brackish water where salinity ranged from 1 to 7 ‰.
