Eggs of the rosalia longicorn are deposited in the crevices of bark and the cracks and fissures formed in drying wood of withering tree trunks (5). Larvae take around three years to develop (3), and towards the end of their development, pupation takes place in a chamber close to the surface of the tree trunk, usually between the end of May and the end of June (6). After metamorphosis, adult beetles emerge between June and August (2), depending on the area and altitude (3). The lifespan of the beetle is only three to six weeks, during which mating and egg depositing must occur. Frequently, competitive males are seen fighting before mating, presumably for access to females. Adult beetles feed on sap exuded from the trees, and also on leaves (5).