Brachinus crepitans is a species of ground beetle in the Brachininae subfamily that can be found everywhere in Europe, except for Monaco, Norway, San Marino, Vatican City, and some islands such as Cyclades, Gibraltar, Iceland, Madeira, Malta, North Aegean, Novaya Zemlya, and Savage Islands.  It can also be found in every Central Asian and Middle Eastern country except for Afghanistan. North African countries have them too.
The species is identical to Brachinus efflans. Majority of species are 6.5–9.5 millimetres (0.256–0.374 in) in length with an average of 8 millimetres (0.31 in). The name of the species derived from a Latin word which means crackle because it makes crackling noise.
Most of the time the species can be found in southern England and southern Wales where its abundant in coastal areas. The inland locations have been sited as well through, the most recent of which are Cotswolds and Northamptonshire where it was discovered in limestones. It was also found in boulder clay in Huntingdonshire, and in Brotheridge Green, an old railway line and wildlife reserve that was located near Malvern, Worcestershire. The species were found in 1970s by Ian L. Crombie.
The species fly from May to June, but the lifecycle is unknown. There is a theory though that the larvae have some external parasites who are feeding on pupae of other beetle species, especially on the ground beetle ones. Examples of such species would be Amara convexiuscula and a staphylinid beetle, Ocypus ater.
When disturbed, the species shoot the liquid onto their potential predators by using their anus. Since one of the glands contains hydrogen peroxide and the other hydroquinone, when two glands mix in a chamber known as the firing chamber with the enzymes added the liquid explodes, and harms unsuspected attackers.
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- "Bombardier beetle (Brachinus crepitans)". ARKive. Retrieved December 28, 2012.
- "Bombardier Beetle Brachinus Crepitans Found Near Honeybourne". WBRC. Retrieved December 28, 2012.