In a rather fascinating clip from the BBC Earth series Natural Curiosities, host Sir David Attenborough explains about a unique ability belonging to both the oogpister and the bombardier beetle. These badass beetles can spray toxic acid from their rear ends to thwart any approaching enemy. Oogpisters are able to develop their venom by eating red ants, while bombardiers naturally carry the acid in their abdomens that they release when needed.
The oogpister beetle has a novel way of deterring potential predators. After feeding on a diet of ants the beetle appears to extract the formic acid they produce for their defence and use it for himself. When threatened, the beetle can spray a small jet of this formic acid straight into the eyes and nose of its attacker. …The master of chemical warfare is the bombardier beetle it can create a chemical reaction within its body so violent that boiling caustic liquid explodes out of its abdomen by pulsing the jet 500 times a second. It keeps its rear end just cool enough to prevent it being cooked.