Divers have captured the first in situ images of a rare Indonesian coelacanth

Nature · Published 3 October 2026 Swipe more like this →

In short: Long considered an elusive deep-sea phantom, the Sulawesi coelacanth has finally been documented in its natural habitat by human divers. Using technical diving gear, researchers observed a live specimen in North Maluku, challenging previous assumptions about where these ancient, lobe-finned fish spend their time and how they behave.

The Sulawesi coelacanth, Latimeria menadoensis, was first identified in 1997 after Arnaz and Mark Erdmann spotted one at a local fish market in Manado. For decades, this enigmatic species remained largely out of reach, documented primarily through bycatch or via expensive, remote-operated vehicles. Because these fish inhabit deep-reef environments, often exceeding 150 meters, direct human observation has been nearly impossible until recent advancements in technical diving.

In October 2024, researchers Alexis Chappuis and Leblond conducted a series of deep dives in the North Maluku Province. Using closed-circuit rebreathers and trimix gases, they reached depths of over 150 meters, encountering a complex, volcanic topography filled with cracks and crevices. At 144 meters, they spotted an adult coelacanth, approximately 1.1 meters long, hovering in the open. Unlike previous theories suggesting these fish remain hidden in caves during the day, this individual was observed swimming freely, potentially displaying defensive behavior with its dorsal fin fully erect.

The team returned the following day and successfully identified the same individual by its unique pattern of white lateral dots. This discovery is a significant milestone for marine biology, as it provides rare data on the species' natural behavior and habitat preferences. However, the exact location remains protected to prevent exploitation, as the species is vulnerable and faces potential threats from unregulated tourism. Understanding these deep-water populations is essential, as researchers continue to investigate whether these distinct regional groups represent genetically separate populations.

Coelacanths are evolutionary marvels, characterized by a slow metabolic rate and a long gestation period, which makes them highly sensitive to environmental disturbances. As the scientific community works to map their biogeography, this recent sighting serves as a reminder of how much of the deep ocean remains unexplored. By documenting these fish in their natural, cold-water environments, scientists hope to establish better conservation strategies for one of the planet's most iconic living fossils.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?

Related

• The prehistoric fish that shocked the world by refusing to stay extinct
• Presumed gone since the dinosaurs, then netted off South Africa
• Observing a living fossil 120 meters below the ocean surface
• The living fossil that proved the Loch Ness Monster was not the only prehistoric survivor
• The prehistoric fish that survived 360 million years of evolution
• The giant fossil penguin that was grey and red, not black and white
• This rodent-toothed dinosaur challenges everything we thought we knew about early bird-like feathers
• Inostrancevia was the apex predator of the Permian, wielding fifteen-centimeter serrated saber teeth.
• Meet the Ictonychinae: The Mustelid Subfamily That Sprays Like a Skunk
• Why these iridescent tropical birds hunt like aerial acrobats in the forest canopy
• Did this ancient creature crawl on land like a seal or swim like a fish?
• Why these tropical birds walk on water and let fathers raise the chicks

More in Vertebrates · More in Nature · Latest · A–Z · All topics