Here we will present some of the unusual inhabitants of the sea…

1.Anglerfish

Anglerfish looking like something out of a science fiction movie.It is quite possibly the ugliest animal on the planet, and it lives in what is easily Earth’s most inhospitable habitat: the lonely, lightless bottom of the sea.

There are more than 200 species of anglerfish, most of which live in the murky depths of the Atlantic and Antarctic oceans, up to a mile below the surface, although some live in shallow, tropical environments. Generally dark gray to dark brown in color, they have huge heads and enormous crescent-shaped mouths filled with sharp, translucent teeth. Some angler fish can be quite large, reaching 3.3 feet (1 meter) in length. Most however are significantly smaller, often less than a foot.

Their most distinctive feature, worn only by females, is a piece of dorsal spine that protrudes above their mouths like a fishing pole—hence their name. Tipped with a lure of luminous flesh this built-in rod baits prey close enough to be snatched. Their mouths are so big and their bodies so pliable, they can actually swallow prey up to twice their own size.

2.Viperfish

The viperfish is one of the most unusual-looking fish in the deep sea. It is also one of the most popular and well-known species. Known scientifically as Chauliodus sloani, it is one of the fiercest predators of the deep. This fish can be easily recognized by its large mouth and sharp, fang-like teeth. In fact, these fangs are so large that they will not fit inside the mouth. Instead, they curve back very close to the fish’s eyes. The viperfish is thought to use these sharp teeth to impale its victims by swimming at them at high speeds. The first vertebra, right behind the head, is actually designed to act as a shock absorber. This fearsome looking creature has a long dorsal spine that is tipped with a photophore, a light-producing organ. The viperfish uses this light organ to attract its prey through a process known as bioluminescence. By flashing the light on and off, it can be used like a fishing lure to attract smaller fish.

Viperfish are found in tropical and temperate waters throughout the world at depths of up to 9,000 feet (2,800 meters). They are rarely seen by humans, although specimens do sometimes show up in the catches of deep water trawlers. These occasional catches provide scientists with unique opportunities to study this elusive animal. Because they live in such deep waters, it is believed that human activity has very little impact on their populations.

3.Giant Isopod

A giant isopod may be one of approximately nine species of large isopods in the genus Bathynomus. They are thought to be abundant in cold, deep waters of the Atlantic.

Giant isopods are of little interest to most commercial fisheries owing to the typical scarcity of catches and because ensnared isopods are usually scavenged beyond marketability before they are recovered. However, in northern Taiwan and other areas, they are common at seaside restaurants, served boiled and bisected with a clean lateral slice. The white meat, similar to crab or lobster in texture, is then easily removed. The species are noted for resemblance to the common woodlouse or pill bug, to which they are related. The few specimens caught in the Americas with baited traps are sometimes seen in public aquaria.

4.Black dragonfish

The deep sea dragonfish, or Grammatostomias flagellibarba, is a ferocious predator in spite of its small size. It is one of many species known to inhabit the deep oceans of the world. This fish grows to about six inches in length. It has a large head and mouth equipped with many sharp, fang-like teeth.

The dragonfish has a long barbel attached to its chin. This barbel is tipped with a light-producing organ known as a photophore. The dragonfish uses this organ like a fishing lure, flashing it on and off and waving it back and forth. Once an unsuspecting fish gets too close, it is snapped up in the dragonfish’s powerful jaws.

The dragonfish also has photophores along the sides of its body. These light organs may be used to signal other dragonfish during mating. They may also serve to attract and disorient prey fishes from deep below. Dragonfishes live in deep ocean waters at depths of up to 5000 feet (1,500 meters). They are found in most tropical regions around the world.

5.Vampie squid

The vampire squid, known to scientists as Vampyroteuthis infernalis, looks more like something that swam out of a late-night science fiction movie. The squid has large fins at the to of its body that resemble large ears. It is very gelatinous in form, resembling a jellyfish more than the common squid. The vampire squid has the largest eyes relative to its body size of any animal. Though it is relatively small, growing to a length of only about six inches, it has globular eyeballs as large as the eyes of a large dog.

The Vampire Squid is almost entirely covered in light-producing organs called photophores. The animal has great control over the organs, capable of producing disorienting flashes of light for fractions of a second to several minutes in duration. The intensity and size of the photophores can also be modulated. Appearing as small white discs, the photophores are larger and more complex at the tips of the arms and at the base of the two fins, but are absent from the underside of the caped arms. Two larger white areas on top of the head were initially believed to also be photophores, but have turned out to be photoreceptors.

Vampire Squid is able to live and breathe normally in the OMZ at oxygen saturations as low as 3%; a feat no other cephalopod, and few other animals, can claim.

6.Bathysaurus

The deepsea lizardfish, Bathysaurus ferox, is a lizardfish of the family Synodontidae, found in tropical and subtropical seas worldwide at depths of between 600 and 3,500 m. Its length is between 50 and 65 cm.

The deepsea lizardfish is a heavy-bodied fish, rounded in cross-section with a broad flattened head containing a large wide mouth. The lower jaw protrudes further forward than the upper. Both jaws and all the mouth bones are heavily covered with conical barbed teeth and most of the jaw teeth are visible outside the edges of the mouth. The strong thick pelvic fins probably serve as props when the fish is resting on the bottom waiting for prey.

Deepsea lizardfish are covered in tough scales and are dark brown or black with black eyes and a black lining to the mouth and gill cavity.

7.Frilled shark

The frilled shark is one of two extant species of shark in the family Chlamydoselachidae, with a wide but patchy distribution in the Atlantic and Pacific Oceans. This uncommon species is found over the outer continental shelf and upper continental slope, generally near the bottom though there is evidence of substantial upward movements. It has been caught as deep as 1,570 m (5,150 ft), whereas in Suruga Bay, Japan it is most common at depths of 50–200 m (160–660 ft). Exhibiting several “primitive” features, the frilled shark has often been termed a “living fossil”. It reaches a length of 2 m (6.6 ft) and has a dark brown, eel-like body with the dorsal, pelvic, and anal fins placed far back. Its common name comes from the frilly or fringed appearance of the gill slits, of which there are six pairs with the first pair meeting across the throat.

Seldom observed, the frilled shark is speculated to capture its prey by bending its body and lunging forward like a snake. The long, extremely flexible jaws enable it to swallow large prey whole, while the many rows of small, needle-like teeth prevent escape. It feeds mainly on cephalopods, while also consuming bony fishes and other sharks. Frilled sharks are occasionally captured as bycatch by commercial fisheries but have little economic value. The International Union for Conservation of Nature (IUCN) has assessed it as Near Threatened, since given its very low reproductive rate even incidental catches may deplete its population.