Our cordial thanks are due to Dr. David R. Smith, the curator of the Symphyta Collection of the Smithsonian Institution (Washington DC, USA), Dr. Hege Vatrdal, the curator of the Hymenoptera Collection, Naturhistoriska riksmuseet (Stockholm, Sweden), Dr. Andreas Taeger, Dr. Stephan Blank and Mr. Andrew Liston of SDEI (Miincheberg, Germany), Dr. Sandor Csosz and Dr. Lajos Zornbori (Budapest, Hungary), and Ms. Suzanne Ryder, Collections Manager of Hymenoptera of the Natural History Museum (London, England) for their kind help during our visits to the above museums to check sawfly types. We also much appreciate Dr. David R. Smith for his helpful discussion on North American species of the genus. The research was supported by the National Natural Science Foundation of China (31172142).