Hermit Crabs and Cockroaches Disperse Seeds of Parasitic Plant on Japan’s Ishigaki Island

A recent study on Ishigaki Island, part of the Okinawa archipelago, revealed that the non‑photosynthetic parasitic plant Balanophora fungosa relies on land hermit crabs (Coenobita brevimanus) and Australian cockroaches (Periplaneta australasiae) to spread its millions of seeds. Professor Kenji Suetsugu of Kobe University initially expected ants to be the main dispersers, but exclusion experiments with mesh nets that allowed only ants showed no fruit consumption. To capture the real dispersers, Suetsugu installed a waterproof digital camera that recorded 6,427 images over 89 hours. The time‑lapse footage showed nocturnal hermit crabs and cockroaches gathering beneath the plants and eating the fleshy fruits, thereby dispersing the seeds.