• flight period;
  • geographic variation;
  • life cycle;
  • seasonal wing dimorphism


The oriental mole cricket Gryllotalpa orientalis exhibits variation in wing dimorphism. In an Okinawa population, no short-winged individuals were observed, and wing dimorphism has not been detected. Flight behavior of G. orientalis was observed from April to October in Okinawa. In contrast, a Hyogo population exhibited seasonal wing dimorphism and long-winged individuals appear from June to September. The flight period of the long-winged morph coincided with this period. Short-winged individuals appeared from September to the following June and they never fly. Both populations showed univoltine life cycles. Considering the possible flight period, wing pattern and life cycle of mole crickets in these two areas, it is presumed that flightlessness is expected to arise when adults can not experience suitable temperatures for flight activity.