A predatory death ball sponge feasting on its victims in the shadowy depths of the ocean floor might appear to be taken from a science fiction horror film, yet this was indeed what was uncovered during a groundbreaking voyage to the Southern Ocean. The death ball sponge was one of 30 species identified, expanding our comprehension of life and ecosystems beneath the waves.
These discoveries in 2025 were led by The Nippon Foundation–Nekton Ocean Census, the Schmidt Ocean Institute, the Southern Ocean Species Discovery Workshop, and the Universidad de Magallanes in Chile. This initiative was a collective endeavor to seek out undiscovered species around the South Sandwich Islands and their vicinity. These islands sit at the boundary of the Southern Ocean and the Atlantic Ocean, southeast of Argentina.
This segment of our oceans has been underexplored, and the expedition aimed to rectify that. By collaborating as an international team, swifter and more thorough research could be achieved. In addition to the captivating death ball sponge, other species found included zombie worms, shimmering scale worms, black corals, among others. Since over 99% of the deep sea remains enigmatic, this research employed cutting-edge technology to help unveil the secrets hidden in areas unreachable to humans.
The newly identified species in the Southern Ocean
The expedition guided researchers throughout the South Sandwich Islands region. They examined the South Sandwich Trench, the calderas of underwater volcanoes, and the seafloor surrounding Montagu and Saunders Islands. More than 2,000 new samples were gathered, and research teams are diligently sorting through all the findings.
The carnivorous death ball sponge was particularly intriguing. The minute hooks adorning its body ensnare prey for nourishment, contrasting with the behavior of known ocean sponges. The zombie worms observed utilized symbiotic bacteria to digest the bone fat of larger creatures, compensating for their lack of a mouth. Additionally, the research teams captured the inaugural footage of a young colossal squid, which might eventually reach up to 45 feet in length and weigh over 1,000 pounds.
The protected iridescent scale worms represented another remarkable discovery, as did a novel species of sea star. They also unearthed unidentified isopods, amphipods, gastropods, bivalves inhabiting volcanoes, and a new genus of sea-pen. This merely scratches the surface of their findings, as all samples are still undergoing continued study and verification. With expeditions like this one, which revealed life thriving at the ocean’s depths without sunlight, along with this record-breaking coral, we are gradually unlocking more about our underwater realm.
