Deep inside an enigmatic ocean-floor animal, researchers have uncovered a tiny organelle that has no known counterpart anywhere on the planet.
Researchers analyzing a rare mollusc found in the South China Sea and off Japan have identified a novel structure within its digestive system. The findings were published in Nature Communications.
The structure has been named a “dragonball” as a tribute to the famous manga series by Akira Toriyama. It exists within the divine dragon glistenworm (“Chaetoderma shenloong”), a mollusc discovered in 2024 and ranked among the top 10 most remarkable finds of that year by the World Register of Marine Species (WoRMS), according to Sciencealert.
When researchers examined the mollusc, specimens dug up from a methane seep in the South China Sea revealed a digestive gland riddled with dragonballs. Surrounded by over 20 membrane layers apiece, these dragonballs contain hundreds of bacteria that can generate organic matter through chemical energy.
Researchers in Japan and China argue that these structures are the first specialized organelles dedicated to chemosynthesis, comparing them to little farms of bacteria that likely help culture microorganisms that oxidize sulfur. Using DNA sequencing, the team found that dragonballs contain only one type of symbiotic, sulfur-oxidizing bacterial species.
Scientists suggest the glistenworm might break down some of the dragonball membranes in its bacteriocytes to release the bacteria into the rest of the cell for digestion, helping the creature harvest food. Alternatively, keeping the bacteria enclosed in oxygen-scarce deep-sea conditions could stop them from consuming a limited resource, leaving more oxygen for the glistenworm itself.
A major scientific finding following the discovery of the first deep-sea hydrothermal vent on the Galápagos Rift in 1977 was that many animals inhabiting reducing habitats, such as hot vents and cold seeps, derive their energy and nutrients by ‘feeding’ on symbiotic bacteria that perform chemosynthesis using inorganic chemicals.
Study authors, Nature Communications
One of the molluscs analyzed in the study was serendipitously collected from a seep site near a mud volcano off the coast of Japan, which extends the known range of the species. “Our discovery of an adaptation from one of the most poorly understood animal groups highlights how little we know about the potential of marine invertebrates, especially infaunal deep-sea taxa,” the authors concluded.
Worth a look
SLU Researchers Simulate Quantum Behaviors Using Classical Light Dynamics
Researchers from Saint Louis University and two German institutions have demonstrated that classical nonlinear light dynamics can induce...
Expert Warns Summer Was a Wake-Up Call and Winter Could Be Dire for Food Supplies
Winter flooding threatens Wales' food supply just as summer droughts and wildfires exposed vulnerabilities in an import-reliant distribution...
NASA’s CHAPEA Mars Crew Finally Emerges After More Than a Year in Isolation
Four research volunteers stepped out of NASA’s Mars Dune Alpha habitat on Oct. 31, 2026, completing the agency's...
Rising Temperatures Halted the Start of a New Ice Age in the Arctic
It was just getting started, everything was normal, the next glaciation was about to happen—and yet it stopped,...