A worldwide community photographing and learning about wildlife
Xylocopa violacea
Their name comes from the fact that nearly all species build their nests in burrows in dead wood, bamboo, or structural timbers. In several species, the females live alongside their own daughters or sisters, creating a sort of social group. They use wood bits to form partitions between the cells in the nest. A few species bore holes in wood dwellings. Since the tunnels are near the surface, structural damage is generally minor or nonexistent. Carpenter bees are traditionally considered solitary bees, though some species have simple social nests in which mothers and daughters may cohabit. However, even solitary species tend to be gregarious, and often several will nest near each other. It has been occasionally reported that when females cohabit, there may be a division of labor between them, where one female may spend most of her time as a guard within the nest, motionless and near the entrance, while another female spends most of her time foraging for provisions.
Xylocopa violacea, the violet carpenter bee, is the common European species of carpenter bee, and one of the largest bees in Europe. Like most members of the genus Xylocopa, it makes its nests in dead wood.
I substitute by Xylocopa violacea, which is the European species since my spotting was in Europe.