Japanese fireflies range from nocturnal luminescent species to diurnal non-luminescent species. Their communication systems are classified into 6 types based on the following criteria: 1) Female responds to male's flashes after a fixed delay; 2) Male is directly attracted by female's light signal, the male perches on a leaf near the female, then the male changes his flashes with twinkling, and copulation behavior is released. However, the female may not respond to the male; 3) Male seeks female calling signal during the male's flying and synchronous flashing, then the male approaches the female, emitting flashes with various patterns, displaying walking-luminescing, sedentary signaling, chasing, and copulating; 4) Male is attracted by continuous luminescent signals of the female, and male perches near the female, then the male distinguishes the female's light organs shape. Thereafter, the male copulation behavior is released by her sex pheromone; 5) Male and female flight occurs in the daytime; when the male approaches the female, copulation is released by the female's pheromone; weak luminescent signals may be fulfilling the function of supplementary communication signals; 6) Luminescent signals have nothing to do with communication between male and female, and copulation is released by a sex pheromone.