Details
Brachinus crepitans
The bombardier beetle is a ground beetle famous for firing a hot chemical spray from the abdomen when attacked. Its small body carries one of the classic insect defenses.
Map: Ecoregions 2017 © RESOLVE (CC BY 4.0) · Natural Earth (PD)
It occurs in Europe, North Africa and western to central Asia in dry grassland, fields, chalky slopes and under stones. Sunny open places are typical.
Adults are about 7-10 mm long. The head and thorax are reddish brown, the wing covers are dark greenish, and the legs are slender.
Mostly active on the ground at night, it hides under stones and debris by day. When threatened, it points the abdomen and releases a hot, irritating spray.
Small insects and other arthropods are eaten. Larvae are thought to use pupae of other beetles and similar prey.
Adults are conspicuous in early summer, and eggs are laid near the ground. Larvae develop in soil or sheltered microhabitats.
The spray is produced by mixing chemicals such as hydrogen peroxide and hydroquinones in a reaction chamber. It is a compact example of complex chemical defense.
