A strange plant hidden in the forests of Japan acts as both a parasite and a doppelgänger, in a novel ruse of the natural world that helps this non-green fungus-like plant spread its seeds. But how did a lifeform with no recognizable consciousness develop such an intricate and successful method of propagation?
To answer this, a botanist from Japan’s Kobe University delved into the strange world of the Balanophora fungosa plant, observing for the first time how hermit crabs pass along its seeds on their journeys through a tropical island near Okinawa. His findings were published in a recent paper in Ecology.
The discoveries significantly alter how botanists previously believed the parasitic B. fungosa propagated and thrived in its forest habitat.
A Parasitic Plant Unlike Any Other
Typically, plants are green due to the chlorophyll inside their cells. They often rely on colorful fruits and flowers to attract the mobile creatures necessary to pollinate or spread the seeds of these stationary lifeforms. B. fungosa turns all of that on its head.
The name “fungosa” comes from its appearance, which is remarkably similar to a mushroom. Instead of greens and bright flowers, B. fungosa is a drab ivory stem with a brown puffball at the top as its main flowering structure, somewhat similar in appearance to the head of a mushroom. Its small form factor further adds to the illusion, with the mushroom simulacra effect completed by its height only reaching about one inch. Furthermore, instead of the typical sweet smell of fruits or flowers, its scent is often compared to that of mice.
Lacking the chlorophyll of green plants, B. fungosa requires an alternate method of obtaining nutrients. It does so by acting as a parasite, attaching to the root systems of larger plants and leeching sustenance from them. Although such parasitic plants reside in almost every biome, they are unusual, comprising only around 1% of flowering plants. The B. fungosa can be found in parts of Asia, Australia, and on some Pacific Islands.
The Mystery Seed Carrier
Earlier studies of B. fungosa had assumed the plant spread its seeds simply via the wind, blowing its offspring to new destinations. With each plant producing about one million seeds, botanists assumed this would be plenty of opportunity to ensure the species’ survival. However, it turned out that there was more to the story.
“Many people assumed that they simply fall by gravity and are carried away by the wind, but the humid and windless forest floor makes this seem rather implausible,” explained author Kenji Suetsugu, a botanist at Kobe University.
Convinced there must be another answer, the Kobe University botanist set up cameras to carefully monitor the plant. He was surprised to find that small hermit crabs consumed the plant’s tiny dry fruit, with the seeds both sticking to their claws and even surviving the passage through the crabs’ digestive systems.
Wherever the crabs went next, they deposited the seeds as they fell from their claws or were expelled in their waste.
Understanding Parasitic Plants
Suetsugu already had good reason to suspect that the wind theory was incorrect. He had spent his botanical career investigating other dull colored fruits of the Balanophoraceae family. In that work, he had discovered that other invertebrate species like cockroaches and ants were responsible for consuming the fruit and spreading the seeds of these related species.
Because the tiny fruits were so easily detachable, Suetsugu suspected ants were the most likely culprit. Yet when he tested this theory by covering the plants with a net designed to keep away anything larger than an ant, he was surprised to find that nothing was eating the fruits. This is when he switched to the camera, allowing him to identify the hermit crab as the culprit.
Using their pinchers, the crabs were so thorough that they sometimes completely cleaned a B. fungosa plant of its fruit in a single evening, bringing the seeds on their journeys, which can stretch as far as 100 miles.
“When it comes to seed dispersal, large vertebrates have received most of the attention,” Suetsugu concluded, “but small-bodied invertebrates are often overlooked. Nevertheless, they may also help maintain seed movement, especially on islands, in fragmented habitats, and on shaded forest floors.”
The paper, “Unexpected Allies: Land Hermit Crabs and Cockroaches Contribute to Seed Dispersal in a Non-Photosynthetic Plant,” appeared in Ecology on August 11, 2026.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org.