Did you know that the ocean has millions of mysteries and singularities, fish being one of them.
We may not all know them since many live at great depths where it’s not possible to carry out studies, however currently it’s known that there are very rare species, actually very rare, strange, peculiar, ugly or as you want to call them.
We also find rare fish in some rivers which are classified as monstrous due to their size or shape.
However, all the species within the ocean are always necessary, so we invite you to read our last paragrah about importance of marine diversity.
To begin, we will study the layers of the Ocean … it’s necessary to know how the depths are divided, in this way to know exactly at what level of the sea the fish lives which you are studying.
Ocean
The water of the ocean is divided into several layers that have different characteristics in salinity, pressure, temperature among others, but today we are interested to know the division that is made according to its depth these are called Pelagic, Mesopelagic, Batial, and Abyssal Zone .
Pelagic and Mesopelagic
Pelagic waters reach up to two hundred meters deep and have enough natural light for photosynthesis to take place.
In turn the Mesopelagic zone starts from 200 meters to 1000 meters deep … in this region only a little natural light penetrates but insufficient to achieve photosynthesis.
Batial
It’s called in this way to the waters and the seabed that are located between 1000 and 4000 meters deep. It has a high hydrostatic pressure. It’s worth mentioning that it’s an area of difficult feeding for these creatures since predation is the only possible means of feeding.
Most of the enigmatic creatures that live there have a slow metabolism and never approach the surface.
Natural light does’t reach this area and the only source of illumination comes from bioluminescent organisms. Fish that live in these depths generally lack eyes and most are black or red.
Abyssal Zone
This area is located between 4000 and 6000 meters deep. It’s a very dark area and sunlight doesn’t reach it.
Moreover, it has a cold environment and an extremely high hydrostatic pressure. Like the Batial zone, fish feeding is limited, some have a jelly-like body and are of enormous sizes, making it impossible for them to approach the surface.
Let’s learn about them
Weird Ocean Fish
As we told you at the beginning there are weird fish distributed throughout the ocean living in different depths, let’s meet some of them in this post.
The hairy frog (Trichobatrachus robustus)
There are only 30 species of this rare and very strange fish. It’s a breed that likes to walk alone. it has a very weird appearance very similar to that of a frog. 
Trichobatrachus robustus has a semicircular body, which is covered with hair-like ramifications as well as a thick mouth.
The hairy frog fish has poisonous spines on its dorsal fin and also on its gill caps.
This species inhabits the warm waters of the ocean between corals and sponges … it feeds on the sea beds remaining hidden until it visualizes its prey on which it pounces in an action similar to that of a frog jumping being another one of the similarities that owns with this amphibian.
Longhorn Cowfish
This is another fish belonging to the rare fish category; Ostracion cubicus is its scientific name and, like the sunfish, it’s a bony fish of the order Tetraodontiformes.
This species is closely related to the Balloon Fish and its colors have a bright yellow hue with black dots. It should be noted that when 
the points grow they become smaller and brown, although in intermediate specimens, their hue is light brown with blue dots surrounded by black dots or black borders.
The largest adults are mustard brown with bluish-green tones and have a bump on their upper lip. Longhorn Cowfish don’ t exceed 45 centimeters in length in their natural habitat.
They are tropical weather fish that live in the pelagic and mesopelagic area from one meter of depth at two hundred and eighty meters.
They are found from the Red Sea and East Africa to Hawaii with seaweed, mollusks and polychaetes being the main elements of their diet.
It’s possible to have this species in captivity but it’s necessary to have rigid measures for its care, which is not easy to achieve so it’s only suggested for expert caregivers.
The long-horn fish is a very calm fish with other species, although they tend to be very aggressive with those of their own species when they are in aquariums. We invite you to read our article Longhorn Cowfish to learn more about this species.
Red lips bat
This species feeds primarily on small fish, shrimp and also small shellfish. It’s worth noting that this fish is not a good swimmer 
(unlike angel fish), and it has adapted pectoral fins that allow it to walk along the ocean floor. It’s a pelagic fish that lives from 3 to 76 meters deep in tropical climates. We invite you to read our article red lips bat to learn more about this spcies.
Blob fish
This species is also known as spot fish and their scientific name is Psychrolutes micropores. The blob fish belongs to the family Psychrolutidae and it’s very rare to find them due to the inaccessibility of their habitat.
Very few human beings have had the privilege of observing this fish. its meat is mostly jelly, its density is a little less than that of water, which allows it to keep floating on the seabed if it wastes its energy.
The gout fish lacks muscles which is considered an advantage as it helps in its feeding. It’s able to swallow any organism that it considers edible that floats in front of it, feeds on sea urchin, molluscs and crustaceans, food It’s scarce in its habitats but due to this passive behavior it does not need much.
Inhabits waters of New Zealand and in eastern Australia at a depth of more than 4,000 meters. They live in the abyssal zone of the ocean at least that is believed. As a curious fact we can mention that he was chosen in 2013 as the ugliest animal in the world and is the image of the Ugly Animal Preservation Society.
This species is considered a living fossil because it has hardly evolved since its appearance is the seas.
Most of its catches were accidental in trawling at the bottom of the sea for this reason IUCN has placed it on its red list of threatened species, classifying it as vulnerable.
Barrel eyes fish
Also known by its scientific name Macropinna microstoma it is the only one that belongs to the genus Macropinna (family Opisthoproctidae).
This fish has been known since 1939 and was discovered by a scientist named Chapman, but it was not until 2004 that the first photograph of this creature was obtained.
The most significant feature of this species is the back of its head which is transparent where the inner part of its eyes can be observed.
Its brain decomposes when they are taken from the depths, the rest of its body is opaque has two dark holes over the mouth the eyes are two spheres with a green hue and are very sensitive to light.
This species is native to the North Pacific and lives between 600 and 800 meters deep, that is, it inhabits the Mesopelagic zone of the ocean.
They are solitary rare fish and a study was carried out on a specimen that feeds on jellyfish and other cdinaries. they also consume seedlings, crustaceans, small jelly fish, some scholars believe that they detect their prey by their silhouette.
Deep sea angler fish
This fish is also known as Melanocetus johnsonii. It belongs to the family Melanocetidae and measures approximately 20 
centimeters. The males are much smaller than females and the largest male identified only measured 2.8 centimeters which is only one tenth of the female.
These fish are red and their most striking feature is the antenna located in their head which leaves from their nose and is shaped like a rod, it has bioluminescent bacteria that light up.
The fish uses this antenna to attract the fish to which it confuses resembling the appearance of a worm and then devours them
With his big teeth to prevent his escape. It can swallow fish that doubles in size since it has a large mouth compared to its body and even small eyes.
To mate, the male bites the belly of the female and after a while merges with her becoming an aggregate of her body, this provides the male with blood and nutrient irrigation and in return receives his sperm continuously.
Males are excellent swimmers and the female prefers to be still and wait for her prey to approach her lure. As a curiosity it’s worth noting that this fish appeared in the animated movie Finding Nemo
These fish inhabit the tropics at a depth that usually ranges from 3,000 to 4,000 meters in the deep ocean area.
Ragged finned firefish
The ragged finned fierefish is also mistakenly called a scorpionfish. Its scientific name is Pterois antennata and it’s one of the rare fish. Its size doesn’t exceed 20 centimeters in diameter and its main 
feature are the amazing and very striking stripes located on its fins as well as its long pectoral antennas whose color varies between black and white. His body is adorned with red, white and brown lines
Pterois antennata is a pelagic fish that has been observed in Africa, Japan, Australia among others.
It’s very important to highlight that it’s a poisonous fish since its radii have poisonous glands, its sting produces painful wounds while the poison causes respiratory paralysis, circulatory insufficiency and fever in humans, these symptoms disappear after a couple of days.
It feeds on shrimp and crab can be housed in captivity taking into account certain precautions. During the day it hides in cracks and under some rocks while at night they hunt. We inviye you to read our article ragged finned fish to learn more about this species.
There are also rare fish in the river as we indicated before before delving into them we will know a little about this body of water.
Let’s meet them
There are also rare fish in the river as we indicated before before delving into them we will know a little about this body of water.
There are also rare fish in the river as we indicated before before delving into them we will know a little about this body of water.
Weird Fish in Rivers
There are also rare fish in the river as we indicated before before delving into them we will know a little about this body of water.
Mekong cat
Description. The catfish of the Mekong is light gray, with silver on the top, and a yellow or cream on the belly. They lack teeth which is interesting, as they are the only species of catfish with such a trait.
The giant Mekong catfish or Mekong catfish is often confused with a shark in the water, they can be very large, up to 10½ feet long and weigh up to 660 pounds. It’s considered the largest freshwater fish in the world.
Distribution.
This species inhabits Southeast Asia, and they tend to live in the deepest areas of water or where water flows rapidly. They are difficult to see, due to their place of residence in the water, but it’s estimated that only a few hundred adults remain in their natural habitat at this point in time.
Behavior.
There are many things that experts don’t know yet about the life of the giant Mekong catfish, and many of their behaviors remain a mystery. 
They aren’t believed to be aggressive, in terms of behavior, however, they are known to be very strong.
They migrate great distances every year, as they need certain environments to perform spawning and breeding.
Feeding habits:
When the Mekong catfish is young, it feeds on various forms of zooplankton. When they are about 1 year old, they begin to change their diet and consume large amounts of algae and plants from the bottom of the water. They spend a lot of time in food consumption, since they need large volumes of it to meet their nutritional needs.
Reproduction.
When the rainy season begins, the giant Mekong catfish will begin to breed. Only the largest will be able to mate, because size is what determines their maturity, and not their age. Although these fish grow fast, and most of them are able to mate at 6 years of life.
Paddle fish
Also called the Mississippi paddle fish, its scientific name is Polyodon spathula these rare fish reach a size of 2.2 meters long and manage to weigh 100 kilograms. their most characteristic feature is their spatula shaped horn from which derives their names both common and scientific.
It’s thought that in his tube there are sensitive electroreceptors which detect his prey also serves to navigate; their diet is based on zooplankton which are filtered by the animal through its feathery gills. It lives lives in slow waters of the Mississippi River.
This species was very common throughout the Midwest of the USA. UU, but overfishing has caused a decline in its population, hunting for its meat and roe as well as the alteration of the river where it lives has influenced the decline of fish reservoirs are an obstacle to its displacement.
Sawfish
It’s a fish of the order elasmobranchs belonging to the Pristidae family. These fish are closely related to the rays.
They measure 1.5 to 6 meters in length. Its main feature is its saw-shaped snout which is covered with sensitive pores that detect movement and electricity. These allow them to detect movement 
and even the heartbeats of their prey that are buried in the seabed.
The sawfish attacks from below and uses its saw very aggressively and sometimes as a defense weapon against other predators such as sharks, dolphins and divers.
The teeth that protrude from their snout are not true teeth but rather dental scales that have been modified. Their body and head are flattened because they spend most of their time lying on the sea floor, the mouth is located at the bottom.
Garpike
This fish has not evolved in the last 100 years and is considered a living fossil. It has an elongated and tubular shape, its snout is large, usually elongated and is disproportionate compared to its body, its skin is covered by hard scales that have a diamond shape, these create a protective armor.
Its fierce appearance is also known by its scientific name Lepisosteiformes, some specimens are huge and measure up to 3 meters in length and can weigh more than 130 kilograms.
It’s a voracious and very efficient predator and has a large mouth with sharp and pointed teeth.
They usually move slowly and still have the ability to accelerate their swimming sharply at an amazing speed.
Most of the time they are still near the surface, letting themselves be carried away by the current and waiting for some prey.
When its food is close enough the fish quickly turns its head and catches the victim often by the side and then flips it and swallows it by the head they are opportunistic predators.
The garpike has been able to survive for so long because it has the ability to adapt to very uncomfortable waters, it has a bladder that fills it by swallowing air which it uses to provide its gills with supplemental oxygen in waters where this element is scarce.
Its meat is edible, but it has a large amount of spine, its eggs have a deadly toxicity to humans and for these reasons its consumption is not common.
Their fishing is usually sporty as it is quoted by fishermen for the great resistance that the fish opposes. They inhabit both freshwater and seawater and are distributed throughout North America, Central America and the Caribbean.
The hard skin and its scales are used in different ways by various cultures, in some cities of Mexico the dissected specimens are sold as souvenirs in Tabasco, Mexico is considered a delicacy, it is part of its typical gastronomy.
Let’s meet it
Https://www.youtube.com/watch?v=qLw-WZXRnVc
Importance of Marine Biodiversity
Biodiversity and marine ecosystems maintain the health of the planet and sustain social welfare
Nowhere else is the importance of biodiversity for sustainable development more essential than in the oceans.
Marine biodiversity, that is, the variety of life in the oceans and seas, is a fundamental aspect of the three pillars of sustainable development – economic, social and environmental – that maintains the healthy functioning of the planet and provides services that support the health, well-being and prosperity of humanity.
The oceans are one of the main biodiversity reserves in the world. They constitute more than 90% of the habitable space of the planet and contain about 250,000 known species and many more that have yet to be discovered, since no more than two-thirds of the world’s marine species have yet been identified1.
The oceans and the life they contain are fundamental to the healthy functioning of the planet, since they supply half of the oxygen we breathe and annually absorb 26% of the anthropogenic carbon dioxide emissions emitted into the atmosphere.
Therefore all the species of the oceans are necessary to maintain the proper biodiversity and ecological balance.
There is increasing evidence to demonstrate the essential role that marine biodiversity plays for the health of the planet and social welfare.
The fisheries and aquaculture sectors are a source of income for hundreds of millions of people, especially for low-income families, and contribute directly and indirectly to their food security. Marine ecosystems provide countless services to coastal communities around the world.
For example, mangrove ecosystems are an important food source for more than 210 million people4, but they also provide many other services such as livelihoods, clean water, forest products and protection against erosion and extreme weather events.
Therefore all the species of the oceans are necessary to maintain the proper biodiversity and ecological balance.
Let’s enjoy this interesting topic….