There are about 28,000 species of fish around the world. They are possessors of a large number of anatomical and physiological adaptations that have allowed them to evolve successfully over the years. In this article we are going to discover what abyssal fish are and their characteristics, incredible marine creatures that are found in the depths of the sea, where sunlight does not reach. Find out more about these deep-sea fish and their interesting anatomy in this article!

What are abyssal fish?

The abyssal fish are a group of species that have the ability to live in the abyssal zone or abyssopelagic zone of the oceans. That is, a portion of the ocean more than 2,000 meters deep. This area is characterized by its extreme environmental conditions. This includes deep seas, extreme water temperatures between 0º-4ºC, high concentration of nutritional salts, as well as a significant increase in pressure and lack of oxygen.

The abyssal zone, or abyssopelagic zone, also represents more than 83% of the ocean and covers about 60% of the land. And yet it is the area that we least know. In its depths, this area remains in perpetual darkness.

Fish that have the correct characteristics to live in these extreme conditions are called abyssal fish. They have a number of characteristics that allow them to survive in such deep oceans. Next we will review all its characteristics and we will know what are some of the fish of this species.

Characteristics of abyssal fish

As we have mentioned previously, these fish share certain characteristics that allow them to survive in the extreme conditions of the abyssal zone of the sea. They are as follows:

  • Skeleton: Netherfish have weak bones as they do not need stronger bones. This is because there are only weak currents in the abyssal zone. Another reason for the weakness of your bones is the fact that they cannot receive the nutrients and minerals, such as vitamin D or calcium, due to the lack of sun and specific components of the water.
  • Body: these fish do not have bright or flashy colors, in fact, many lack color and appear transparent. This helps them blend in with their environment that is in perpetual darkness. Many abyssal fish have bioluminescence that allows them to produce light from their bodies. These fish also have a very soft and flexible body that allows them to float in the depths of the sea.
  • Mouth: Many species of abyssal fish have extremely large mouths compared to their bodies. In fact, many have mouths larger than their bodies. This is an adaptation to the lack of food sources. The development of the mouth and stomach allows them to feed on larger prey. Even their prey are sometimes bigger than they are. Some species appear to simply consist of a head and a large jaw. Others have huge, sharp teeth that don’t fit in the mouth when closed.
  • Eyes: some abyssal species have huge eyes, while others do not even have eyes. Eyeless abyssal fish will need to rely on other senses to locate prey, mate, and avoid predators. When it comes to fish that do have eyes, their eyesight is extremely sensitive. In fact, they are 100 times more sensitive to light than the human eye.

Some of the abyssal fish that are known are: monkfish, viper fish, Saccopharynx ampullaceus, pelican fish or dragon fish.