Marine researchers have formally identified 149 species new to science among more than 1,000 organisms collected from a chain of seamounts in the eastern Indian Ocean, according to findings reported by Mongabay and published in the journal Deep-Sea Research Part II.
The survey, led by Tim O'Hara of Museums Victoria, drew on samples gathered between 2020 and 2022 aboard Australia's RV Investigator around seamounts near Christmas and Cocos (Keeling) Islands, southwest of Java, at depths ranging from 94 to 5,431 meters. A team of 33 researchers from Australia, New Zealand, Canada and the United States catalogued the haul, which included previously unknown sea cucumbers, greeneye fish, parasitic barnacles, black corals and sea worms, along with 23 fish species never before recorded in Australian waters.
Among the more striking finds was what the team nicknamed a "shark graveyard" — a seafloor scattered with roughly 1,000 shark teeth spanning more than 22 million years of evolution, including teeth from great whites, makos, tiger sharks and the extinct giant Megalodon.
Seamounts act as underwater oases, their currents concentrating nutrients that support life far denser than the surrounding open ocean, which is part of why they draw disproportionate scientific interest despite covering only a small fraction of the seafloor. The Christmas and Cocos Islands seamount chain had barely been sampled before this expedition, leaving much of its biodiversity undocumented until now. Researchers described the region as a critical gap in the scientific record, and warned that seamount ecosystems worldwide face growing pressure from climate change, deep-sea trawling and prospective seabed mining before they have even been fully mapped.
The formal species descriptions, drawn from specimens now held in Australian museum collections, are expected to continue for years as taxonomists work through the full catalogue from the expedition.
