A remarkable discovery has been made in the Southern Ocean, where scientists have uncovered a variety of new deep-sea species, including a unique carnivorous sponge referred to as a “death ball.” This sponge employs a lethal method to ensnare its prey, showcasing the extraordinary adaptations of life in extreme underwater environments.
This biodiverse community consists of unusual organisms, including bone-eating worms and other previously unidentified species. The expedition revealed that many of these creatures are adapted to thrive near underwater volcanoes. The findings were made possible by a remotely operated underwater vehicle that explored an area previously hidden beneath an iceberg.
In January 2025, marine researchers were presented with an unprecedented opportunity when an iceberg, nearly the size of Chicago, broke away from the George VI Ice Shelf. This event exposed a previously inaccessible seabed, prompting the Schmidt Ocean Institute”s vessel, the R/V Falkor (too), to deploy the ROV SuBasitan to investigate.
During its exploration, the vehicle discovered hydrothermal vents, vibrant coral gardens, and even a juvenile colossal squid that had never been documented before. The expedition resulted in the collection of around 2,000 specimens across 14 different animal groups, along with thousands of images and hours of video footage.
Currently, researchers are in the process of classifying the newly found species. At a recent workshop hosted by the University of Magallanes in Chile, 30 of these species were confirmed as new to science. This classification is part of a larger initiative known as The Nippon Foundation-Nekton Ocean Census, which aims to document at least 10,000 new species over a decade.
Michelle Taylor, Head of Science at the Nippon Foundation-Nekton Ocean Census, emphasized the significance of these findings, stating, “The Southern Ocean remains profoundly under-sampled. To date, we have only assessed under 30 percent of the samples collected from this expedition, so confirming 30 new species already shows how much biodiversity is still undocumented.”
Among the noteworthy discoveries is the “death-ball” sponge, scientifically classified as Chondrocladia sp. nov.. Its spherical shape and predatory behavior distinguish it from typical sponges, which primarily feed by filtering water. Additionally, researchers observed “zombie worms” (Osedax sp.), known for their ability to burrow into whale bones and consume collagen.
The expedition revealed various other new species, including armored and iridescent scale worms, diverse sea stars, isopods, amphipods, and rare gastropods and bivalves that can survive in volcanic and hydrothermal environments. Several other species remain unassessed but may also be new to science, such as black corals and a potential genus of sea pens.
A team of taxonomists at the workshop utilized imaging and DNA barcoding to classify the specimens. Ongoing evaluations of the Southern Ocean”s biodiversity will continue, with newly identified species being curated in the open-access Ocean Census Biodiversity Data Platform, making the information accessible to both researchers and the public.
This groundbreaking expedition highlights the rich and largely unexplored biodiversity of the Southern Ocean, paving the way for future discoveries and a deeper understanding of marine ecosystems.
