The life cycle varies among firefly species, but the following example applies to many of them. Mating takes place in the dark, in the spring and early summer. Partners find one another thanks to light signals associated with courtship behaviour. In many species, the male emits flashing signals in flight and is attracted by the luminous response of the female, which remains stationary.
After mating, the female lays her eggs in a damp spot. She dies soon afterward, while the male perishes after mating. The eggs hatch about one month later. The larvae are flattish and long. The number of moults depends on the species. Fireflies spend most of their lives in the larval stage. In Quebec, they hibernate in this form.
To complete this stage, the larvae makes itself a shelter in the soil. In the spring, it metamorphoses into a pupa. After about ten days, the insect breaks open the case and the adult firefly emerges. It remains underground for a few days and then sets out to find a partner.
Most known firefly species have a life cycle that lasts two years.