A team of scientists from the Monterey Bay Aquarium Research Institute (MBARI) said on September 8, 2025, that they’ve discovered three new species of snailfish. They first spotted the snailfish in 2019 while exploring the deep-sea floor off the coast of California. Their advanced underwater technology made the discovery possible.
After the researchers collected the specimens, they collaborated with scientists from the State University of New York at Geneseo (SUNY Geneseo), the University of Montana and the University of Hawaii at Manoa to try to identify them. The scientists conducted both morphological and genetic analyses and have now confirmed that these three species are previously unknown to science.
The scientists published their study on August 27, 2025, in the journal Ichthyology and Herpetology.
Three new snailfish species identified
Researchers from SUNY Geneseo recently described three new deep-sea snailfish species: the bumpy snailfish (Careproctus colliculi), the dark snailfish (Careproctus yanceyi) and the sleek snailfish (Paraliparis em).
The bumpy snailfish is notable for its pinkish coloration, large eyes set on a rounded head, broad pectoral fins with extended upper rays and a body covered in an uneven texture. The dark snailfish features a completely black body, a rounded head and a mouth that sits horizontally. Meanwhile, the sleek snailfish has a slender, flattened black body, lacks a suction disc and has a sharply angled jaw.
Snailfish belong to the family Liparidae. They’re known for their distinctive body shape. They usually possess a large head, soft and gelatinous flesh covered by loose skin and a thin tail. Many species have a suction disc on their underside, enabling them to cling to the seafloor or even “hitch a ride” on larger deep-sea creatures such as crabs. In shallower waters, snailfish often attach themselves to rocks and algae, much like true snails.
So far, scientists have identified over 400 species of snailfish worldwide. These fish occupy a diverse range of habitats, from shallow intertidal pools to the ocean’s deepest trenches. One particular snailfish species even holds the record for living at the greatest ocean depth ever recorded for a fish.
This is the bumpy snailfish. A team of scientists from MBARI found, recorded and collected the animal in 2019, about 62 miles (100 kilometers) off California’s central coast. Image via © 2019 MBARI (used with permission).
How was the discovery made?
In 2019, MBARI’s Biodiversity and Biooptics team made a remarkable discovery of the bumpy snailfish during an expedition aboard the now-retired vessel Western Flyer. Senior scientist Steven Haddock led the team as they explored the Monterey Canyon, located roughly 62 miles (100 kilometers) off California’s central coast. Using the remotely operated vehicle Doc Ricketts, the team observed this small snailfish swimming near the ocean floor at a depth of 10,722 feet (3,268 meters).
The adult female snailfish they collected measured 3.6 inches (9.2 centimeters) and displayed unique features that hadn’t been seen in previous deep-sea snailfish documented by MBARI in California. This finding prompted Haddock to contact Mackenzie Gerringer, an associate professor at SUNY Geneseo, who specializes in the physiology and ecology of deep-sea marine life. Gerringer’s extensive expertise in deep-sea snailfish made her the perfect collaborator for further analysis.
Around the same time, Jeff Drazen and his team discovered the dark and sleek snailfish during a 2019 expedition using the Alvin submersible. Drazen, who was a postdoctoral fellow at MBARI at the time, made this find at Station M, a deep-sea research site off California’s central coast at about 13,100 feet (4,000 meters) depth.
MBARI’s ROV Doc Ricketts is a robotic submersible equipped with advanced cameras and scientific instruments to explore the ocean’s midnight zone and abyssal seafloor. Steven Haddock and his team operated it from a research vessel at the surface when they discovered the bumpy snailfish. Image via Randy Prickett/ Erich Rienecker/ © 2018 MBARI (used with permission).
Cutting-edge technology
Mackenzie Gerringer collaborated with researchers from the University of Montana and the University of Hawaii at Manoa – including Jeff Drazen – to conduct an in-depth study of the three snailfish specimens. Their goal was to evaluate how these fish compared to known species in terms of similarities and differences.
The team employed a variety of methods, such as detailed imaging, morphological assessments and genetic comparisons. By using microscopy, micro-CT scans and precise measurements, they gathered extensive data on the size, shape and physical characteristics of the fish. This analysis clearly demonstrated that these specimens were distinct from any previously documented snailfish species.
In addition to physical examination, the researchers sequenced the DNA of the fish to compare their genetics with other snailfish. This helped place the new species within the evolutionary tree of the Liparidae family and confirmed their status as previously undiscovered species.
Currently, the only confirmed observation of the bumpy snailfish comes from Steven Haddock’s 2019 sighting, leaving its full geographic distribution and depth range largely unknown.
However, while reviewing MBARI’s underwater video archives, researchers found footage from 2009 that might show an earlier sighting. The fish filmed off the Oregon coast was initially thought to be a bigtail snailfish (Osteodiscus cascadiae), but it could potentially have been the bumpy snailfish.
These are the sleek and dark snailfish. Images via Jeffrey Drazen/ Ichthyology and Herpetology (CC BY 4.0).
The importance of collaborating
MBARI’s cutting-edge technology plays a vital role in documenting the rich diversity of species living in the deep ocean. This information is critical for making informed decisions about ocean management and for protecting marine ecosystems and coastal communities from threats like climate change and deep-sea mining. Steven Haddock emphasizes MBARI’s commitment to sharing data and technology with the scientific community, which fosters collaboration and expands our understanding of deep-sea life. Haddock said:
MBARI seeks to make ocean exploration more accessible by sharing our data and technology with our peers in the science community. We welcomed the opportunity to collaborate with researchers from SUNY Geneseo to expand our understanding of life in the deep ocean, especially since documenting deep-sea biodiversity is critical to detecting any changes that may be occurring in this environment.
For over 30 years, MBARI and global scientists have gathered unique data at Station M, a deep-sea research site that has provided important insights into ocean ecosystems and their links to climate. The species Paraliparis em was even named to honor this site and the dedicated researchers involved.
MBARI’s advanced technology supports deep-sea species research, guiding ocean conservation and fostering global scientific collaboration through open data sharing. Image via © 2019 MBARI (used with permission).
Snailfish: small creatures, big insights
Deep-sea ecologist Mackenzie Gerringer brings her expertise in physiology, taxonomy and functional morphology to study how snailfish survive in extreme environments: enduring crushing pressure, near-freezing temperatures and total darkness. She reflects on the discovery of three new snailfish species as a testament to the vast unknowns still hidden beneath the waves and the power of curiosity driving scientific exploration. According to Gerringer:
The deep sea is home to an incredible diversity of organisms and a truly beautiful array of adaptations. Our discovery of not one, but three, new species of snailfishes is a reminder of how much we have yet to learn about life on Earth and of the power of curiosity and exploration.
With the deep ocean as the planet’s largest habitat, many species remain unidentified. As threats like climate change and mining escalate, the urgency to document and understand deep-sea biodiversity grows. Over nearly four decades, MBARI and its collaborators have discovered more than 300 new species, sharing specimens and video footage worldwide to support ongoing research. Each discovery, no matter how small, adds an essential piece to the vast puzzle of our planet’s deep ocean.
Researchers collected both Paraliparis em and Careproctus yanceyi at the same location (white circle). A white square marks the collection location of Careproctus colliculi. Image via Ichthyology and Herpetology (CC BY 4.0).
Bottom line: Researchers have identified three species of snailfish in the Pacific Ocean. Millions of creatures inhabit the vast abyss of the oceans. So, why is the discovery of these tiny animals so important?
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