Anglerfish are our mysterious, deep-sea lifeform of the week

Are you afraid of the dark? When it comes to anglerfish, you should fear the light. They live in the depths of the ocean and use a biological lantern to attract their prey. The female is the dominant fish, and there are many more unusual facts about these mysterious and fascinating creatures.

Beauty lies within

Normally, when talking about fish, one thinks of small, colorful animals. Well, this fish is the complete opposite of that. The anglerfish has a disproportionately large head with jaws full of teeth, in some cases very long and sharp. It is a medium-sized fish, about 12 inches (30 cm) long, but the largest anglerfish can measure 4 feet (1.2 m).

An anglerfish is not a pretty fish, but who cares? It is an impressive fish that adapts to the harsh conditions of the deep ocean. Not to mention the unique way it hunts; it uses the lantern on its head! Someone had a brilliant idea …

Few creatures are as resilient as anglerfish

There are more that 200 species of anglerfish. They are found in two types of water. They live in the water found above the continental shelf, which is no more than 650 feet or 200 meters deep. Or in the abyssal plains, which are located at an ocean depth between 2.5 and 3.7 miles (4 and 6 km) deep.

If there’s barely any light at 650 feet, imagine the level of darkness, the cold and the high pressure encountered by these fish inhabiting the ocean floor.

Anglerfish have a lifespan of 25 years. Isn’t it impressive how some species manage to survive in such ruthless environments?

Anglerfish have an anatomy built for survival

The anglerfish that inhabit the depths of the ocean do not have it easy, since they are subjected to very harsh conditions. Plus, food is scarce and difficult to find. So, to make the most of every opportunity, they have developed expandable jaws and stomach.

Their jaws can extend, allowing them to swallow large prey. In addition, the teeth of anglerfish are curved toward the inside of the oral cavity and can move. So, once the prey enters, it cannot escape.

On the other hand, their body is very flexible. They can eat prey up to twice their own size.

Anglerfish preferred prey is crustaceans, snails and small fish, but since the anglerfish can expand its size, it also eats large fish and even octopuses or squid.

A brilliant trap

No matter how many survival skills anglerfish have, nothing can be seen in the dark. Therefore, evolution had a brilliant idea for our favorite little monster fish.

Basically, there’s a lantern on the head of anglerfish, located at the end of a type of fishing rod. The part that shines is at the end, falling in front of the eyes and mouth. Naturally, the fish that inhabit these dark areas are attracted to light. And as luck would have it, anglerfish can see better than they do.

Anglerfish may swim aimlessly with their lantern shining, waiting for something to take the bait, or they may wait buried in the sand.

This bioluminescent lantern’s light is generated through a chemical reaction. It is not genetically passed on from the parents; anglerfish emit light thanks to bacteria capable of generating it. These microorganisms are acquired from the environment, in what is called symbiosis. So the bacteria receive nutrients from the fish and, in return, the fish gains an organ that lights up and allows it to attract prey … and mates.

Female power

In the case of anglerfish, there is sexual dimorphism. This means that one gender is very different than the other. One obvious difference is female anglerfish are much larger than the males.

Also, only the females have a lantern. Males do not need this shiny trap, nor large bodies, nor long, sharp teeth. However, males possess an impeccable sense of smell that they use to sniff out their future partner in the pitch-black expanse of the deep sea.

If it is difficult to find food at this depth, it is even harder to find a girlfriend. Therefore, in many species, once the male finds a female, the male never separates himself from her.

The male bites the female’s belly, releasing an enzyme that dissolves the skin under the bite and fuses his mouth with her body. In this way, he will draw sustenance from her for the rest of her life. The males become parasites of the females. Some females can be parasitized by up to six males.

Baby anglerfish develop on their own

The good thing is that, in return, the female will have a supply of sperm ready whenever she is ready to mate. Fertilization is external, so the male and female release sperm and ovules at the same time. The adults do not monitor the fertilized eggs; they develop independently.

In some species, once reproduction is over, males leave the females.

Bottom line: Are you afraid of the dark? Well, anglerfish are not! That’s because they have a lantern on their head that they use to attract prey in the dark deep sea. Also, they have a huge mouth full of long, sharp teeth. As you can see, it’s truly an amazing monster fish!

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