If you have ever walked through a forest after the rain and suddenly spotted something that looked like an alien egg cracking open on the ground, there is a good chance you encountered a stinkhorn mushroom. Known scientifically as Phallus impudicus and commonly referred to as the “stinkhorn,” this bizarre fungus has earned a reputation as one of the most frightening-looking organisms in the natural world. But what exactly is it, and why does it evoke such strong reactions from anyone who sees or smells it?

A Strange Life That Begins as an Egg

The life of a stinkhorn mushroom starts with a stage that confuses even experienced foragers: the “witch’s egg.” This rounded, rubbery structure sits partially buried in soil or grass, resembling a mysterious biological pod. When sliced open, it reveals a gelatinous interior and a folded structure that will later become the mushroom’s mature form. Many people describe this stage as looking like an alien embryo or a scene from a sci-fi movie, and it’s easy to understand why.

Within just a few hours—sometimes overnight—the egg splits open dramatically. From inside, the mushroom’s tall, sponge-like stalk emerges, growing at a surprisingly fast speed. Some stinkhorns can shoot up several inches in a single morning, making them one of the fastest-growing fungi on the planet.

Continued on the next page