Larvae tunnel between the layers of the leaf, attacking and killing leaves closest to the water. The larvae or pupae can be found by separating the layers of the leaf. Larvae feed for 5 to 12 days before pupating. Adults emerge after 5 to 9 days and live 2 to 4 months. Under ideal conditions, the life cycle can be completed in as few as 15 days. In cool weather, the life cycle can extend for more than one month.