MBARI's advanced underwater technology reveals a new species of deep-sea snailfish • MBARI

The bumpy snailfish is one of three new species of deep-sea snailfish described by MBARI collaborators at SUNY Geneseo.

Why It Matters

MBARI technology is helping researchers document deep-sea biodiversity, providing much-needed information to help guide decision-making about the ocean and protect marine life and communities from threats like climate change and mining.

MBARI’s advanced underwater technology is revealing the remarkable species that thrive in the deep sea. In 2019, MBARI researchers encountered an unfamiliar pink snailfish swimming just above the seafloor. New research from MBARI collaborators has confirmed this individual represents a species previously unknown to science: the bumpy snailfish (Careproctus colliculi).

A pale pink deep-sea snailfish swims just above the deep seafloor. The snailfish has a tapering, tadpole-shaped body. It is facing the left side of the frame and has large eyes, a wide mouth, broad fins, and a bumpy appearance. The background is dark blue water with several drifting bits of organic material and sediment. — The bumpy snailfish (*Careproctus colliculi*) has a distinctive pink color, pectoral fins with long fin rays, and a unique bumpy texture. Image: © 2019 MBARI

A team of researchers from the State University of New York at Geneseo (SUNY Geneseo), with scientists from the University of Montana and the University of Hawaiʻi at Mānoa, published their findings in the scientific journal Ichthyology and Herpetology, describing the bumpy snailfish observed by MBARI researchers alongside two other snailfishes from the abyssal seafloor offshore of California.

“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,” said MBARI Senior Scientist Steven Haddock, who led the research expedition that encountered the bumpy snailfish.

Uncovering secrets to survival in extreme environments

Snailfishes belong to the family Liparidae. They typically have a large head, jelly-like body covered in loose skin, and narrow tail. Many snailfish species have a disk on their belly that allows them to grip the seafloor or hitchhike on larger animals, such as deep-sea crabs. Shallow-water snailfishes often cling to rocks and seaweed, curling up like a snail.

Scientists have described more than 400 different species of snailfish worldwide. These fishes make their homes in a variety of ocean habitats, from shallow tide pools to deep-sea trenches. In fact, a snailfish holds the record for the deepest-dwelling fish.

SUNY Geneseo Associate Professor Mackenzie Gerringer studies deep-sea physiology and ecology and has conducted extensive research on deep-sea snailfishes. Her research uses comparative techniques in taxonomy, functional morphology, and physiology to understand how fishes are adapted to life under crushing pressure, frigid cold, and perpetual darkness in the ocean’s depths.

“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,” said Gerringer.

Chance encounters spark new discoveries

An MBARI remotely operated vehicle descends into the ocean. The robotic submersible has a bright yellow float on top of a black metal frame with a pair of black metal manipulator arms, a large camera, and several colored wires. The robot was photographed shortly after deployment, with its tether visible at the top of the frame. Bright blue water and one of the twin hulls of an MBARI research ship are visible in the background. — Operated by a team of scientists and pilots aboard a research vessel at the surface, MBARI’s ROV *Doc Ricketts* is a robotic submersible equipped with advanced cameras and scientific instruments for exploring the ocean’s midnight zone and abyssal seafloor. Image: Randy Prickett and Erich Rienecker © 2018 MBARI

MBARI’s Biodiversity and Biooptics Team observed the newly described bumpy snailfish during an expedition aboard the institute’s retired flagship research vessel Western Flyer. Haddock and his team were exploring the outer reaches of Monterey Canyon, approximately 100 kilometers (62 miles) offshore of Central California, with MBARI’s remotely operated vehicle Doc Ricketts at a depth of 3,268 meters (10,722 feet) when they observed this small snailfish swimming above the abyssal seafloor.

MBARI researchers collected this individual—an adult female 9.2 centimeters (3.6 inches) long—for further study in the laboratory. With features unlike other deep-sea snailfishes that MBARI had encountered offshore of California, Haddock reached out to Gerringer for more detailed analysis. MBARI frequently collaborates with expert taxonomists to review footage and specimens. These partnerships offer fresh perspectives that often spark new discoveries.

New additions to the family

An animation alternates between a photo of a pale pink deep-sea snailfish swimming and a lab scan of the fish’s skeleton. The snailfish has a tadpole-shaped body. It is facing the camera and has a wide mouth, large lips, broad fins, and a bumpy appearance. The background is dark greenish-blue water with several drifting bits of organic material. The lab scan of the fish’s skeleton shows the bones of the fish’s skull and backbone in white on a solid black background with a white text label that reads CT Scan at the bottom right. — CT scans conducted at Friday Harbor Laboratories revealed the skeleton and internal anatomy of the bumpy snailfish (*Careproctus colliculi*), complementing MBARI’s video observations to provide a detailed description of the fish’s morphology. Animation: Steven Haddock/MBARI, snailfish image © 2019 MBARI, CT image © 2025 Mackenzie Gerringer

Gerringer and researchers from the University of Montana and the University of Hawaiʻi at Mānoa, including former MBARI postdoctoral fellow Jeff Drazen, examined the bumpy snailfish as part of a comprehensive analysis of three unusual snailfish specimens collected offshore of California. The team combined imaging, morphological, and genetic approaches to compare these snailfishes to other known fishes.

Using microscopy, micro-computed tomography (micro-CT) scanning, and careful measurements, the team collected detailed information about the size, shape, and physical characteristics of the three fishes, distinguishing them from all known species. They also sequenced the DNA of the specimens to compare these animals to other snailfishes and determine their evolutionary position in the family Liparidae. Their examination confirmed that all three snailfishes were new to science. The team has made their CT scan data publicly available via MorphoSource and genetic sequence data via GenBank (PV300955-PV300957 and PV298545-PV298546).

In addition to the bumpy snailfish, the SUNY Geneseo team described the dark snailfish (Careproctus yanceyi) and the sleek snailfish (Paraliparis em).

A slender deep-sea snailfish swims above the seafloor. The snailfish has a dark brown body with a tapering translucent white tail. The fish is swimming to the left side of the frame. The background is greenish-brown muddy seafloor. — Many deep-sea snailfishes are hard to identify from video alone. MBARI researchers have observed a snailfish that appears to be the newly described slender snailfish (*Paraliparis em*), but without collecting a specimen for closer analysis, we cannot be sure. Image: © 2006 MBARI

The bumpy snailfish has a distinctive pink color, a round head with large eyes, wide pectoral fins with long uppermost rays, and a bumpy texture. The dark snailfish has a fully black body with a rounded head and horizontal mouth. The sleek snailfish is distinguished from other snailfishes by a long, black, laterally compressed body, absence of a suction disk, and prominently angled jaw.

Both the dark and sleek snailfishes were collected in 2019 by Drazen and colleagues during an expedition with the submersible Alvin at Station M, a research site operated by MBARI offshore of Central California at a depth of approximately 4,000 meters (13,100 feet). MBARI scientists and researchers worldwide have leveraged a unique 30-year dataset collected by a suite of advanced instruments at Station M to make several important discoveries about abyssal ecosystems and the ocean-climate connection. The species name of the sleek snailfish, Paraliparis em, recognizes this unique research site and the people and programs that have supported the Station M time series.

Haddock’s encounter is the only confirmed observation of the bumpy snailfish, so the full geographic distribution and depth range of this species remain unknown. However, a closer look at MBARI’s extensive archive of underwater video suggests this species may have been previously encountered offshore of Oregon in 2009 and mistaken for a similar species, the bigtail snailfish (Osteodiscus cascadiae).

Cataloging life in the depths

The deep sea is the largest living space on Earth. The inky waters beneath the ocean’s surface teem with life, including many species unknown to science. With threats like climate change and mining putting deep-sea communities at risk, documenting the residents of this environment is more urgent than ever.

Over the past 38 years, MBARI researchers and our collaborators have discovered more than 300 new species. We share video footage and specimens with taxonomy experts around the world, giving other researchers access to the deep sea. MBARI science and technology are helping establish a baseline understanding of ocean health and deep-sea biodiversity so we can better assess how climate change, pollution, mining, and other human activities will affect the marine ecosystems. From the mesmerizing “mystery mollusc” to the carnivorous harp sponge, each discovery is a new piece of the puzzle.

Funding for this work was provided by the U.S. National Science Foundation Division of Ocean Sciences (OCE-1829612), the David and Lucile Packard Foundation, and the SUNY Geneseo Research Foundation.

Learn more about these new deep-sea snailfishes from MBARI’s collaborators at SUNY Geneseo.

Research Publication:

Gerringer, M.E., S. Suplicz, J.L. Palmeri, L. Fregosi, B.H. Woodworth, M. McMahon, S. Shepard, L.M. Peoples, and J.C. Drazen. 2025. Descriptions of three newly discovered abyssal snailfishes (Liparidae) from the Eastern Pacific Ocean. Ichthyology and Herpetology. 113(3): 487–506. https://doi.org/10.1643/i2024069

Story by Senior Science Communication and Media Relations Specialist Raúl Nava

For additional information or images relating to this article, please email pressroom@mbari.org.

You might be interested in:

MBARI’s advanced underwater technology reveals a new species of deep-sea snailfish