Record-breaking ‘gigantic’ deep-sea limpet species named after ONE PIECE character

Researchers from Japan Agency for Marine-Earth Science and Technology (JAMSTEC) have discovered a deep-sea limpet species 5,922 metres beneath the northwestern Pacific Ocean, marking the deepest known habitat for any true limpet (subclass Patellogastropoda).

Described as a new species in the open-access journal Zoosystematics and Evolution, the limpet was found on hard volcanic rock 500 kilometres southeast of Tokyo, Japan. The gastropod measures up to 40.5 mm in shell length, a remarkably large size for a true limpet from such depths.

The new species was named Bathylepeta wadatsumi, a reference to Wadatsumi, the god of the sea in Japanese mythology, and the character “Large Monk” Wadatsumi, from the manga series ONE PIECE. The character’s enormous size mirrors that of the newly discovered limpet.

The researchers behind the discovery paid further homage to the world’s most popular manga series in their acknowledgements, writing:

“We also take this opportunity to salute Eiichiro Oda for continuing to chart the epic voyage of ONE PIECE (1997–), which reminds us that the greatest voyages are driven by freedom, camaraderie, and an insatiable thirst for discovery.”

The new species was collected using the crewed submersible DSV Shinkai 6500, making it the first time a member of the genus Bathylepeta has been observed and photographed live on its natural rocky substrate, rather than being dredged using a net. The use of submersibles is instrumental in accessing these habitats, allowing for direct observation and collection of previously overlooked organisms. 

Dr. Chong Chen, lead author of the research paper, said: “Even in an age of sophisticated remotely operated vehicles, there’s often an edge to the human eye on the seafloor. Crewed submersibles like Shinkai 6500 let us explore with intention and nuance—spotting lifeforms like Bathylepeta wadatsumi that might otherwise be missed entirely.” 

Beyond its taxonomic significance, the study has broader ecological implications as B. wadatsumi appears to graze on sediment layers over rock, indicating a specialised role in processing organic matter in deep-sea ecosystems.

The findings underscore the need for more comprehensive explorations of rocky abyssal habitats using submersibles to reveal the true diversity and distribution of Bathylepeta and other animals relying on such habitats.

Original source

Chen C, Tsuda M, Ishitani Y (2025) A new large-sized lepetid limpet from the abyssal northwestern Pacific is the deepest known patellogastropod. Zoosystematics and Evolution 101(3): 1249-1058. https://doi.org/10.3897/zse.101.156207