A Parasitic Plant That Looks Like a Mushroom Has Been Sending Hermit Crabs to Do Its Dirty Work

On the forest floor of Ishigaki Island near Okinawa, there's a plant doing something that required a time-lapse camera, a net experiment and one very surprised botanist to fully document. Balanophora fungosa looks like a mushroom, lives as a parasite on the roots of nearby trees and apparently moves its seeds via hermit crab. From both ends of the hermit crab, to be precise.

A single plant can turn out up to 1 million seeds, each inside its own speck of dry fruit, and nobody knew how they traveled. Many assumed they simply fell by gravity or drifted on air currents, a pretty implausible theory for a humid, windless forest floor, as Kobe University botanist Suetsugu Kenji noted. Suetsugu's earlier research had found ants and cockroaches involved in dispersal, and he suspected ants were the main event; the plant's yeasty smell and detachable fruits seemed tailor-made for them.

So he covered the plants with nets fine enough to let ants through but block larger animals. Nothing inside touched the fruit. He swapped in a camera instead and had it take a photo every 50 seconds. Across 6,427 images and about 89 hours, it showed land hermit crabs and cockroaches arriving after dark to eat the fruit.

The crabs left with fruit stuck to their claws, 86 per crab on average. They also swallowed seeds whole, and some came out the other end still capable of growing. A land hermit crab can roam up to 328 feet (100 meters), so its droppings may land a long way from the parent plant.

Suetsugu calls it the first evidence that hermit crabs spread seeds both ways, on the outside of their bodies and through the inside. The ants, his first suspects, never touched the fruit.

Read the full story at Popular Science, August 11, 2026

Hot Take: Anyone who has found a tomato growing out of the compost pile knows this trick. The plant just outsourced it to something with claws.