Strange "alien" fish: Transparent head, glowing green eyes

This strange fish has a unique appearance. This fish has a transparent head and green eyes that glow in the dark.

In addition to researching and learning about aliens living in space, scientists also discovered that there are still many strange and wonderful life forms on Earth. In particular, this strange life form exists under the blue sea water far offshore.

Specifically, marine biologists caught a strange fish in Monterey Bay, off the coast of California, USA. This fish has an alien-like appearance, discovered at a depth of more than 600m. In this position, the sun can shine. This “alien” fish is called barreleye fish.

It is known that this fish was discovered by marine biologists working at the Monterey Bay Aquarium Research Institute (MBARI) using a remotely operated vehicle (ROV). Accordingly, the remotely controlled vehicle has recorded more than 5,600 successful dives.

In total, more than 27,600 hours of video were recorded. However, experts have only encountered barreleye fish only 9 times. In fact, this fish was first described in 1939.

On the head of this fish there are two indentations that look like eyes but are not. Nearby are the barreleye fish’s actual eyes, which are glowing green. These eyes are located in a very special position, allowing barrel-eye fish to observe the water ahead to look for food. The habitat is at great depth and food is scarce, so this fish must turn its eyes forward to be able to observe a large area.

Evolutionary biologists confirm that vision developed so strongly because of the harsh living environment, without sunlight. Its eyes are tubular, with a multi-layered retina and a large lens.

In 2019, a study showed that the barreleye fish’s unusual eyes can rotate within a transparent shield. This ability helps this fish find food and see far ahead.

In particular, the barrel-eye fish’s head has a very special transparent color, revealing bright eyes. According to marine biologists, this special fish uses large, flat fins to easily control its motionless body in the water.

This makes it impossible for surrounding creatures to see the barreleye fish clearly. Prey such as small fish and plankton above will not see it. However, it can clearly see its prey to attack. Once it identifies the target, this fish will attack quickly from the darkness and swallow its prey.

In the ‘Into the Deep’ project, researchers expect ocean exploration using ROVs will lead to discoveries of deep-sea creatures such as cactus jelly, bubble coral and Japanese spider crabs.