Deep Sea Discovery: New Species Found Off Argentina

This deep sea discovery is rewriting what scientists know about life in the South Atlantic. Researchers have identified 57 species never before described by science in Argentina's Mar del Plata submarine canyon, plus five entirely new genera. The announcement, made in September 2026, ranks among the largest single hauls of unknown ocean life in recent years — and one of the newcomers is a translucent, horned sea cucumber nicknamed Loki.

The breakdown reads like a census from another planet. Twenty of the new species are copepods, tiny crustaceans that drift through the water column and anchor marine food webs. Another 22 are echinoderms, the group that includes sea cucumbers and crinoids. Fourteen more are cnidarians — octocorals, sea pens and stony corals — and the final newcomer is a scaphopod, a tusk-shell mollusc. According to Ocean Decade's report on the findings, the new genera span corals, sea cucumbers and crustaceans.

The standout is Loki, formally listed as Peniagone sp. As reported by DIVE Magazine, the animal was found at a depth of 2,577 metres, with a see-through body and a pair of horn-like appendages that reminded researchers of the Norse trickster. It is one of up to ten new sea cucumber species uncovered during the project, and the discovery shows how much weird, beautiful biology is still sitting on the seafloor within reach of modern robots.

How twenty scientists named a hidden world in two weeks

The haul came out of a Species Discovery Workshop hosted at Universidad Maimónides in Buenos Aires from July 13, 2026 to July 24, 2026. Twenty taxonomists and early-career researchers from Latin America and Europe spent the fortnight examining specimens with integrated taxonomy techniques — combining anatomy with DNA analysis — and logging each discovery directly onto an open-access platform for new marine species.

The workshop was led by the Nippon Foundation-Nekton Ocean Census in partnership with the Schmidt Ocean Institute, alongside Argentina's national research council CONICET and the Museo Argentino de Ciencias Naturales. "International cooperation in taxonomy is critical, especially in groups with few active specialists," said Dr. Daniel Lauretta, a principal investigator at CONICET, in the announcement. He noted that the workshop sped up the recognition of species new to science while training a new generation of local deep-sea taxonomists.

Most of the specimens came from the Schmidt Ocean Institute's Underwater Oases of the Mar del Plata Canyon expedition in August 2025, when the research vessel Falkor (too) sent the remotely operated vehicle SuBastian down into the canyon. The team also worked through historical samples from earlier CONICET expeditions. Underwater photography from the dives captured highlights including an orange-red octocoral at nearly two kilometres down and sea pens that anchor some of the canyon's most complex habitats.

Why this haul matters more than the photos

The deep sea is the least explored ecosystem on the planet, and scientists are in a race to document it before it changes. According to the Nippon Foundation, the official registration of a new species can take up to thirteen and a half years — meaning some creatures may vanish before they are ever documented. The Ocean Census was launched in April 2023 with a goal of finding at least one hundred thousand new marine species in its first decade, precisely because the traditional pace of taxonomy cannot keep up.

The newcomers matter for practical reasons, not just wonder. Copepods sit at the base of ocean food webs that ultimately feed fish stocks humans depend on, and deep-sea corals and sea pens create habitats that shelter countless other animals. Every species catalogued now becomes part of the baseline that future conservation decisions — and debates over deep-sea resource use — will be measured against.

There is also more still to come. Some of the corals and sea pens found in the canyon may represent an entirely new family, pending genetic analysis, and the workshop's success is a blueprint for similar rapid-discovery events around the world. "Discovering 57 new species and five new genera in just two weeks demonstrates the speed and power of collaborative taxonomy," said Dr. Michelle Taylor, Ocean Census head of science, in the announcement. For a generation that grew up with the whole ocean supposedly mapped, this deep sea discovery is a reminder that whole neighbourhoods of life are still waiting for their names.

For more on how scientists are tracking our changing oceans, browse the science desk and read how ocean heat readings are revealing where climate models miss.