An underwater robot exploring the deep seas captured the first video footage ever of a creepy-looking anglerfish — a creature that looks so menacing it is sometimes called the "black seadevil."

Researchers from the Monterey Bay Aquarium Research Institute (MBARI) were using a remotely operated vehicle (ROV) to explore the Monterey Canyon ocean trench, a steep seafloor canyon in California that extends about 95 miles (153 kilometers) into the Pacific Ocean.

The robotic sub came across the anglerfish around 1,968 feet (600 meters) below the surface. The researchers used the ROV to take pictures and video of the anglerfish, and then captured the deep-sea creature and brought it back to MBARI for closer study. [See photos of the creepy anglerfish]

The anglerfish is named for the long strip of flesh that sticks out of its head. This "fishing pole" has a luminous bulb that looks irresistible to smaller prey fish or squid swimming through deep and dark waters. Once the prey gets too close, the anglerfish snatches it with its long, needlelike teeth.

Anglerfish are the most rarely seen of all deep-sea fish, said senior scientist Bruce Robison in a video created by MBARI. The fish captured by MBARI researchers is only 3.5 inches (9 centimeters) long. The anglerfish is being kept in a tank at MBARI, but the researchers don't expect it to live very long.

MBARI marine scientists think this is the first video footage captured of this anglerfish species. The video shows that the fish has a broken tooth on the left side of its jaw, and scientists are not sure if the tooth will grow back once it falls out.

The milky eyes of the anglerfish are useless in the dark ocean depths where it lives. Instead, the fish relies on the small white dots covering its body, which it uses to sense the movement of other fish around it.

Male anglerfish are much smaller than female anglerfish, and they look a lot less intimidating. The tiny males don't have a fishing pole or lure and are almost incapable of finding their own food. Once they find a female anglerfish, the helpless males attach themselves to the females. Their bodies actually fuse together, and the male's skin and major organs waste away. Eventually, the male fish becomes an accessory for the female that can provide sperm when the female is ready to breed.

The rare footage and observations of the live anglerfish could help scientists learn more about the behavior of this elusive deep-sea creature.

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