HONEY BEE: EXPLODING TESTICLES.
The reproductive cycle of bees is fascinating - and complex. But here's the short story: a queen is selectively bred in a special "queen cell" in the hive and fed royal jelly by worker bees to induce her to become sexually mature.
A virgin queen that survives to adulthood without being killed by her rivals will take a mating flight with a dozen or so male drones (out of tens of thousands eligible bachelors in the colony). But don't call these drones lucky because during mating, their genitals explode and snap off inside the queen!
Strange as it is, this actually makes evolutionary sense: the snapped-off penis acts as a genital plug to prevent other drones from fertilizing the queen. But tell that to the dead drone whose penis just exploded.