57 New Deep-Sea Species Found Off Argentina — Meet Loki

On October 1, marine scientists confirmed a discovery that rewrites part of the ocean's family tree: 57 deep-sea species previously unknown to science, recovered from a single submarine canyon off the coast of Argentina. According to the Ocean Census, the international program behind the find, the haul also includes five entirely new genera — whole branches of the tree of life that no human had ever classified. The announcement makes the Mar del Plata Submarine Canyon one of the most productive deep-sea species frontiers ever documented in the South Atlantic.

The numbers behind the expedition are striking. Researchers examined 20 copepods — tiny crustaceans that drift through the water column — and every single specimen turned out to be new to science, even though the team had sorted only a tenth of the material collected. Alongside them came 22 echinoderms, 14 cnidarians including deep-sea corals, and a single scaphopod mollusk from the tusk-shell group. As reported by Fox Weather, the canyon yielded dozens of animals that expand the known diversity of one of the least explored regions on Earth.

The breakout star is a translucent, horned sea cucumber nicknamed Loki after the Norse trickster god. Found at a depth of 2577 meters, the animal's ghostly body and crown-like appendages made it an instant favorite among the taxonomists who examined it during a two-week identification workshop in Buenos Aires. Images of Loki, credited to the Schmidt Ocean Institute, show a creature that looks less like an animal and more like a rumor — pale, delicate, and utterly alien to sunlit eyes.

How the canyon gave up its secrets

The specimens were gathered last August by the remotely operated vehicle SuBastian during an expedition to the Mar del Plata canyon, a vast underwater gorge carved into Argentina's continental slope. Back on land, specialists convened by the Ocean Census spent a fortnight in the Argentine capital sorting, photographing, and sequencing the catch — work that continues as genetic analysis confirms which finds truly represent new deep-sea species and which are cryptic variants of already-known animals. A follow-up expedition is already scheduled for the first quarter of next year to revisit the canyon and probe even deeper sections of the slope.

The copepod result deserves a second look. Copepods are among the most abundant animals on the planet, yet the ocean's smallest inhabitants remain its least catalogued. That every copepod examined from this canyon was new to science — drawn from just a fraction of the samples — suggests the South Atlantic's deep waters hide a diversity that current textbooks barely hint at. For taxonomists, who describe only a few thousand marine species in a good year, a single canyon delivering dozens of new deep-sea species at once is the equivalent of striking a library where every book was thought to be blank.

Why a canyon full of strangers matters

For anyone who grew up hearing that we have better maps of the Moon than of the seafloor, this is the receipts. Every new deep-sea species that gets formally described tightens the baseline that conservation policy depends on: you cannot protect what you have not catalogued. The South Atlantic's high seas are being negotiated under new international frameworks right now, and discoveries like this one give negotiators concrete evidence that the region holds unique biological wealth worth safeguarding, according to marine researchers involved in the census effort.

There is a bigger scientific reckoning hiding in the fine print. The Ocean Census team notes that marine biodiversity baselines for regions like this one may be structurally wrong — built from sparse historical sampling that missed entire communities. If one canyon can quietly harbor this many undescribed animals, the models used to set fishing quotas, plan marine protected areas, and assess the risks of deep-sea mining could be working from a map with most of the landmarks missing. Each new deep-sea species added to the record is a small correction to that map.

What happens next is refreshingly open. The Ocean Census publishes its specimen data and imagery for other researchers to use, and the Schmidt Ocean Institute's footage from the SuBastian dives is available for classrooms and curious viewers alike. Scientists caution that formal species descriptions — the peer-reviewed papers that give each animal its official Latin name — will take months or years, and the true tally from the canyon will almost certainly grow as the remaining samples are examined. Loki may have a proper scientific name by the time the next expedition sails. Until then, a horned ghost at the bottom of the Atlantic is a decent reminder: the largest habitat on Earth is still mostly unread.

Source: the Schmidt Ocean Institute announced the findings in September 2026.