In Okinawa's coastal forests, brown puffballs protrude from roots of trees like unwanted warts. Although they might appear to be mushrooms, the balls are plants. To be more specific, they are fruits. To be even more specific, they are clusters of up to a million fruits that each encase a tiny seed, fruits made larger and more dazzling by their proximity to each other, fruits designed like pavé diamonds.

But Balanophora fungosa, also known as fungus root, is not strange because it looks like a mushroom, or even because it has an unreasonable number of fruits. It is strange because it has no chlorophyll with which to photosynthesize, and it has no roots with which to drink water. Instead, the fungus root survives by parasitism, entrenching itself on the roots of trees. In other words, it's a freaky little plant. Petra Svetlikova, a plant researcher at the Okinawa Institute of Science and Technology, said as much in a statement: "It’s a fascinating example of how something so strange can evolve from an ancestor that looked like a normal plant with leaves and a normal root system."

For a long time, scientists could not figure out how the fungus root made more fungus roots—that is, how it reproduced. The disco ball of one million tiny dry fruits clearly needed to be dispersed. But how, or by whom? Kenji Suetsugu, a plant biologist at Kobe University, has finally figured it out. In a new paper in Ecology, he reveals the identities of the pollinators, which are even stranger than the fungus root itself. It seems the plant has hitched its propagation wagon to cockroaches and hermit crabs, the latter of which have never previously been observed to pollinate a plant.

Suetsugu is no stranger to strange pollinators. He's previously published on plants pollinated by Amami rabbits, ants and camel crickets, and roaches and crickets. He distrusted prior theories of how B. fungosa managed to spread its seed. "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," he said in a statement. He knew other Balanophora species with firmly attached fruits were dispersed by cockroaches and crickets, insects capable of biting off the fruits. He knew Balanophora species with easily detached fruits were dispersed by ants.

The fruits of B. fungosa were easy to pluck, so ants seemed the first suspect. But when Suetsugu covered the bulbous fruits with a mesh that allowed ants but not larger animals, the plant's fruits were totally untouched. Suetsugu switched tactics, setting up a time-lapse camera to see who would come by for a dull, dry sort of fruit salad. To his surprise, the fungus root's most frequent visitors were Australian cockroaches, who would often flock to a single fruit. But most voracious visitors were Indonesian hermit crabs. The crabs plucked the fruits easily with their pincers and could finish an entire puffball in one night.

But eating a fruit does not guarantee you take part in its pollination. Suetsugu knew what he had to do next. He collected the droppings from the roaches and crabs that fed on the fungus root and examined their contents. He found a handful of intact seeds in each hermit crab poop, as well as several intact seeds in the roach droppings. (I will refrain from posting those photos, but rest assured that they are there, and they are intact.) These two unorthodox pollinators were helping to preserve this plant by defecating at great distances from their fruity meals. This digestive style of pollination, known as endozoochory, is most often associated with vertebrates. Birds and monkeys, for example, have big and roomy guts that can accommodate seeds without splintering them.

Suetsugu's paper offers the first direct observation of a land hermit crab dispersing seeds. But it adds to mounting evidence that many invertebrates disperse seeds in their feces, including earthworms, beetles, crickets, crabs, and slugs. Reports of these pollinations were long relegated to the realm of anecdote. But Suetsugu and colleagues recently published a paper extolling the surprising abundance and excretory powers of invertebrate who pollinate this way. And Suetsugu suspects that non-photosynthetic plants like the fungus root, which have small and robust seeds and live in windless areas, might particularly benefit from such pollinators. In other words, the stranger the plant, the stranger the pollinator. Pollination isn't just bees nosediving into the pollen-powdered stomachs of flowers; it's also oily little brown roaches scurrying over a brown growth and hermit crabs eating thousands and thousands of seeds and then going for a stroll before shitting them out.