Green Shield Bug - Life Cycle

Life Cycle

In Europe, the bright green shield bugs appear in May, having hibernated as imagos during the winter. They fatten for a month and then mate in June. Copulation is back-to-back in typical Heteropteran mating position, as they are not flexible enough for both to face forward. The female lays her eggs in hexagonal batches of 25 to 30, and a single female will lay three to four batches. The imago's colouration changes over the summer from green to a greenish brown almost a bronze, before death. After the eggs hatch, the green shield bug enter their larval stage (which is really their first nymphal stage) where, in general, they remain together in sibling communities. This is made possible by the excretion of a aggregation pheromone. In case of danger, another pheromone is released which causes dispersal. The larval stage is followed by four more nymphal stages with a moult between each one. The green shield bug displays different colouration during each nymphal stage, light brown, black or green-black, and in the final stage, the imago, is bright green with short wings. Usually the imago stage is reached in September, with hibernation occurring in November.