Australian scientists have unveiled a treasure trove of marine biodiversity from the depths of the Coral Sea, with over 110 new-to-science species identified from a groundbreaking research voyage. Led by the Commonwealth Scientific and Industrial Research Organisation (CSIRO), this expedition has spotlighted the untapped wonders of one of the world's least explored ocean realms, highlighting the critical role of deep-sea research in understanding and safeguarding Australia's vast marine heritage.

The Coral Sea Marine Park, spanning nearly one million square kilometres east of the Great Barrier Reef, encompasses seamounts, atolls, and deep reefs that plunge to over 3,000 metres. This protected area, Australia's largest marine park, remains a frontier for discovery due to its remoteness and technological challenges in accessing such profound depths. The recent findings underscore how much remains unknown about deep-sea ecosystems, where evolutionary processes unfold in isolation, producing unique adaptations unseen in shallower waters.

The Voyage: Charting the Unknown Depths

In late 2025, the CSIRO research vessel RV Investigator embarked on the Coral Sea Frontier voyage, a 35-day mission departing from Brisbane and venturing as far as Mellish Reef, approximately 1,000 kilometres offshore. Supported by a $5 million grant from the CSIRO Marine National Facility and backed by the Australian Government's National Collaborative Research Infrastructure Strategy (NCRIS), the expedition involved 24 scientists deploying advanced tools to sample uncharted territories.

Chief Scientist Dr. Will White, a renowned shark and ray expert from CSIRO, led the team. 'During the voyage it was incredible to observe plenty of unique, deep-sea creatures in locations from seamounts and atolls to unexplored deep reefs,' White remarked. The RV Investigator's deep-towed camera system, capable of surveying seafloors up to 3,900 metres, captured high-resolution footage of elusive life forms, complementing physical collections via trawling nets and sleds.

Over 6,000 individual specimens were collected, forming the basis for months of post-voyage analysis. This collaborative effort with the Nippon Foundation-Nekton Ocean Census not only gathered physical samples but also fed data directly into the Ocean Census Biodiversity Data Platform, the world's first open-access digital gateway for newly discovered marine species.

Taxonomic Workshops: Unlocking Species Identities

Following the voyage, a series of unprecedented taxonomic workshops across Australia brought together local and international experts. These sessions, described as the largest ever for marine animals in the country, combined morphological examination with DNA sequencing to confirm novelties. Specimens were preserved in national collections, including CSIRO's Australian National Fish Collection and state museums like the Australian Museum, ensuring long-term accessibility for future generations.

Dr. Claire Rowe, Marine Invertebrates Collection Manager at the Australian Museum, participated in both the voyage and workshops. She highlighted the challenges with jellyfish: 'Jellyfish specimens are usually fixed in formalin... This preservation method makes DNA extraction more challenging. Voyages such as the recent one to the Coral Sea allow us to take tissue samples... from these deep-sea specimens.' Her team's work has yielded first-ever DNA from rare deep-sea jellyfish, revolutionizing identification.

Dr. Candice Untiedt, CSIRO marine ecologist, emphasized: 'Turning [specimens] into knowledge depends on taxonomic expertise... Discoveries across invertebrate groups like jellyfish, sponges and polychaete worms are emerging.' This rigorous process has already confirmed over 110 new species, with projections exceeding 200 as cryptic forms—those indistinguishable by appearance alone—are genetically parsed.

Star Species: Sharks, Rays, and Ghostly Chimaeras

Among the highlights are four new cartilaginous fish identified by Dr. White himself, showcasing his expertise honed over nearly 80 species discoveries in his career. The deepwater catshark (genus Apristurus) stands out as a tropical novelty: 'very dark-bodied, almost flabby – truly deepwater things, very slow moving, [with] lots of little teeth,' White described. This flabby form aids buoyancy in crushing pressures.

The ghost shark, or chimaera (genus Chimaera), features a rat-like tail, plump nose, and prominent dorsal spine—relics of ancient lineages predating modern sharks. Two rays complete the quartet: a long-snouted skate (Dipturus) with eye thorns and a stingaree (Urolophus) from the Kenn Plateau. These finds expand our knowledge of chondrichthyans, vital apex predators regulating deep-sea food webs.

Footage also revealed rare sightings like the sand tiger shark (Odontaspis ferox), a deepwater grey nurse relative, underscoring the park's role as a biodiversity hotspot.

Photo by Karl Solano on Unsplash

Invertebrate Marvels: From Brittlestars to Jellyfish

Beyond fish, invertebrates dominate the haul. Brittlestars, crabs, sea anemones, sponges, polychaete worms, and jellyfish abound, many new to science. Anemones, in particular, excited Rowe: 'There does look like there’s some new species of anemones, which is quite exciting.' These sessile filter-feeders anchor deep-sea communities, hosting symbiotic microbes and sheltering smaller fauna.

Polychaetes and sponges reveal evolutionary quirks adapted to perpetual darkness and cold. Tripod fish, standing on stilt-like fins, and 'dumpling' angelfish exemplify bizarre morphologies. Genetic barcoding addresses cryptic diversity, where look-alikes hide genetic distinctions, vital for accurate censusing.

Preservation innovations—tissue sampling pre-formalin fixation—enable molecular insights, bridging morphology and genetics for robust taxonomy.

Technological Frontiers in Deep-Sea Exploration

The RV Investigator's arsenal proved pivotal. Its deep-towed camera delivered unprecedented imagery, revealing behaviours impossible via nets alone. Trawls targeted benthic layers, while sleds skimmed surfaces. Post-collection, workshops integrated AI-assisted imaging and high-throughput sequencing.

This tech ecosystem, funded by NCRIS, positions Australia as a deep-sea leader. Partnerships like Bush Blitz enhance capacity, training early-career taxonomists—a pipeline for marine science talent.

Conservation Imperatives: Protecting the Abyss

These discoveries arrive amid threats. Climate change warms the Coral Sea by nearly 0.5°C in decades, with record sea surface temperatures. Overfishing targets high-value species, while proposed deep-sea mining risks irreversible damage to seamounts—biodiversity pinnacles.The Guardian reports underscore urgency: 'With so many threats... we need to understand what’s out there before it’s lost.'

Parks Australia's Shaun Barclay noted: 'These discoveries will directly inform how we manage and conserve this globally significant marine ecosystem.' Baseline data guides zoning, no-take areas, and monitoring, preventing extinction of unnamed species.

Broader Implications for Marine Science

The voyage illuminates deep-sea connectivity. Seamounts act as 'stepping stones' for larvae dispersal, linking ecosystems. New species inform phylogenies, revealing evolutionary hotspots. Economically, biodiversity underpins fisheries and biotech—chimaeras yield cartilage insights, anemones inspire pharmaceuticals.

Dr. Michelle Taylor of Nekton stressed real-time data sharing: 'To ensure high-quality data is visible to the global community.' This accelerates global censuses, countering the 'taxonomic impediment'—expert shortages hindering descriptions.

Challenges persist: describing species takes 10-20 years per White, with 50-year gaps between voyages possible. Sustained funding is crucial.

Photo by Karl Solano on Unsplash

Careers in Deep-Sea Research: Opportunities Down Under

This expedition exemplifies Australia's marine research prowess, fostering careers in taxonomy, genomics, and ecology. CSIRO and universities like James Cook and Queensland offer research positions, from postdocs to faculty roles. Early-career scientists gain hands-on via Bush Blitz, building skills in ROV operation, sequencing, and fieldwork.

With CSIRO's ongoing commitments, aspiring marine biologists can contribute to conservation. Explore Australian academic jobs in ocean sciences, where voyages like this propel discoveries and policy.

Future Horizons: Sustaining Discovery

Expect more publications from this trove, with DNA unlocking cryptic diversity. Repeat voyages, enhanced AI taxonomy, and international alliances promise acceleration. As White warns, 'It may be the last time we get into that Coral Sea area for 50-odd years'—urgency drives investment.

Global context: Ocean Census aims 100,000 species by 2030. Australia's Coral Sea contributions position it centrally, blending research with stewardship for resilient oceans.

Toni Moate, CSIRO Marine National Facility Director, affirmed: 'RV Investigator provides the crucial capability for deep-sea discovery.' Sustained voyages ensure baselines evolve with threats, securing legacies for generations.