When a male honey bee climaxes during sex, his testicles explode and then he dies.
27
The pea aphid insect explodes itself thereby sacrificing its life to protect its relatives from predators.
3
Some older/less efficient worker termites will develop 'backpacks' of toxic chemicals that explode when the termite is threatened. They are essentially used as suicide bombers when the colony is being attacked.
8
When dragonflies mate, their tails form a love heart.
22