How Do Beetles Use Chemical Warfare?

When they are picked up or otherwise disturbed, ground beetles respond by secreting large quantities of poisonous chemicals called quinones. These ooze through the mouth and also from the joints of the body of the insect. This causes a blistering effect and acts as a deterrent to the ants, toads or humans that try to interfere with them.

Bombadier beetles are masters at using quinones. They release strong quinones from special glands in the abdomen, ejecting the chemical out into the air using powerful muscular contractions. The secretion bursts out of the beetles body and explodes noisily on contact with the air, going off like a little bomb.

It is boiling hot and forms a cross between a hot spray and a puff of smoke and smells foul. Bombadier beetles can make repeated attacks in quick succession, a very effective form of chemical defense.

Eleodes beetles don't get quite the same explosive effect but they compensate by aiming carefully. They squirt poison directly into the face of their attacker.