Backwards-walking fish caught on video in the South China Sea

An armored searobin spotted during Dive 11 of NOAA’s Papahānaumokuākea ROV and Mapping expedition in 2025. This was one of the team’s “fishier” dives thus far, with numerous fish sightings, including this armored sea robin, seen at a depth of approximately 493 meters (1,6,17 feet). Armored sea robins use modified fins to move across the seafloor and branched "whiskers" in front of their mouths to help them sense food. Image: NOAA Ocean Exploration, 2025 Beyond the Blue Get the Popular Science daily newsletter💡 Breakthroughs, discoveries, and DIY tips sent six days a week. By signing up, you confirm you are 16+, will receive newsletters and promotional content and agree to our Terms of Use and acknowledge the data practices in our Privacy Policy. You may unsubscribe at any time. The deep-sea is filled with weird creatures: goblin sharks (Mitsukurina owstoni), vampire squid (Vampyroteuthis infernalis), and… walking fish? For the first known time, a team of scientists in China filmed a strange, shrimp-like fish walking backward along the seafloor. The fish, Scalicus engyceros, is a species of armored searobin, a group of fish known for weird anatomy. Their bodies are covered in bony plates, while stiff free fin rays stick out of its pectoral rays like tiny legs it can use to “walk.” Walking behavior in 'Peristediid' fishes in the South China Sea The new study, published in the journal Ocean-Land-Atmosphere Research, not only provides video evidence of the animal’s sea-floor strolls, but it also marks the first time backwards locomotion has been described in fish. “[Our] study delivers a paradigm-shifting revelation: the deep-sea fish Scalicus engyceros, a representative of fishes characterized by highly specialized free pectoral-fin rays, is among the few fish species known to walk,” said Han Tian, a postdoctoral researcher at Sun Yat-sen University in Guangzhou, in a statement. The video was taken from a deep-sea diving vehicle in the northern South China Sea that also helped the researchers observe the fish’s other unique traits. It has outward-extending barbels that resemble a farmer’s rake. While the barbel makes it awkward for the fish to walk, it provides “an advantage in probing, digging, or hunting for food buried in the sediment,” according to the team. Like other deep-sea creatures, Scalicus engyceros also has large eyes. The researchers note that the fish did not seem to react to the approaching vehicle, but it did appear to react to its light beam before swimming away. This suggests its eyes have at least some sensitivity to light, perhaps pointing to the fish not having lived in this habitat for very long. While there’s still much to learn about this mysterious creature, advancements in technology are helping scientists better understand the life way beneath our oceans’ surface. “Modern deep-sea diving vehicles allow not only discovery of new species but also add a new in situ, functional dimension to the study of species based solely on the morphology of preserved specimens,” said Tian. “By observing deep sea animals alive in their surrounding environment, we can gain insight into the adaptation and evolution of the species. These walking fish harbor far more novel behavioral and evolutionary adaptations than previously assumed.” 2026 Popular Science Home of the Future Awards 39 products that will improve your everyday life.