Researchers at the Monterey Bay Aquarium Research Institute (MBARI) have caught a particularly elusive deep-sea fish on camera.
The highfin dragonfish (Bathophilus flemingi) can grow to be seven inches long and usually lives at depths of 740 to 4,500 feet below sea level, according to NPR.
“MBARI researchers have observed a few different dragonfishes in the depths of Monterey Bay, but this one is the rarest we’ve encountered,” the institute wrote on Twitter May 3. “In more than three decades of deep-sea research and more than 27,600 hours of video, we’ve only seen this particular species four times!”
Dragonfish are a type of deep-sea predator that can grow to be up to 20 inches and live as far down as 14,800 feet below sea level, according to MBARI. They typically catch their prey – usually fish or crustaceans – by staying still in the water and catching them as they swim by. They are aided in this endeavor by their coloring: They are tinted with some of the blackest blacks in the natural world.
However, the highfin dragonfish is unique in that its scales have a bronze tint, Live Science reported.
“They are just amazing animals, and part of what is appealing is that color pattern,” MBARI senior scientist and discovery team leader Bruce Robison told Live Science.
Like the black of its deep-sea cousins, the highfin dragonfish’s bronze might also help it to camouflage because it absorbs the bit of blue light that can still reach the fish’s habitat.
“But when we shine our white lights on it, it’s just gorgeous,” Robison said.
The highfin dragonfish has another notable feature that allows it both to catch prey and stay safe from predators: bioluminescence. It uses a sort of bioluminescent fishing rod that dangles from its chin to attract smaller animals until they swim within reach of the dragonfish’s jaws. At the same time, it protects itself with a series of light organs on its rear that disguises its silhouette from creatures swimming below.
“Many predators hunt by looking upwards trying to spot the silhouette or the shadows of their prey against the light of waters above,” Robinson explained.
The rare creature was spotted during an expedition in MBARI’s Western Flyer research vessel, the institute wrote on YouTube. They found it just outside of Monterey Bay at a depth of around 980 feet.
“Often the real joy of those trips comes from the stuff you don’t anticipate,” Robinson told Live Science.