Fangtooth

Looking like it just swam out of a horror movie is the amazing fangtooth. Known scientifically as Anoplogaster cornuta, this menacing creature haunts the deep waters of many of the world's oceans. The fangtooth gets its name from its rather impressive looking teeth, which are actually the largest teeth of any fish in the ocean when taken in proportion to body size. Because of its unusually grotesque appearance, the fangtooth has earned the nickname "ogrefish". It is also referred to by some as the common sabretooth.

Although the fangtooth may look like a true monster, it is actually a small fish, reaching a maximum length of only six inches (16 centimeters). It has a short, deep body and with a large head and mouth. The head contains numerous mucous cavities separated by serrated ridges. These cavities are covered over with thin skin. The body of this fish is covered with small, prickly scales, and its color varies from black to dark brown. It has very small eyes that are set high on the head. To compensate for relatively poor eyesight, the fangtooth has developed an unusually prominent lateral line which helps it to sense movement and vibration from the surrounding water.

Undoubtedly the most noticeable characteristic of this species is the teeth. They are so large that the fangs on the lower jaw actually slide into specially formed pockets in the roof of the mouth when the jaw is closed. These pockets extend into sockets on either side of the brain. These teeth become a formidable weapon as the fangtooth hunts squid other small fish. Because its eyesight is not good, many researchers think the fangtooth hunts by a process known as chemoreception, where it essentially must bump into something edible as it searches the dark waters. It is believed that these fish migrate to upper layers of the ocean to feed during the night and then return to the murky depths during the day. If a fangtooth wanders too close to the surface, it risks becoming a meal for larger fish species such as marlin or tuna.

Fangtooth reproduce by laying eggs that hatch to reveal tiny plankton-sized larvae. Their spawning frequency is not well known, although it has been observed between June and August. As the larvae eventually grow into the juvenile stage, they look completely different from the adults. They are light gray in color with long spines on their heads. They also have larger eyes and slightly smaller teeth. This difference in appearance initially caused scientists to assume that it was a different species entirely. Unlike the adults, the juveniles feed by filtering plankton from the water using specially formed gill rakes. These gill rakes disappear as they reach maturity. The juveniles begin to resemble the adults when they reach a size of about three inches. At this time they begin to descend down to deeper waters. Scientists still do not know how long they live.

The fangtooth is found throughout the world in temperate and tropical ocean regions including the waters off the coast of Australia. It is one of the deepest living fish species yet discovered. These fish are commonly seen between 600 and 6,500 feet (200 - 2,000 meters), but have been observed as deep as 16,000 feet (5,000 meters). The pressure at these great depths is intense and the water temperature is near freezing. The fangtooth is more robust than other deep water species. Researchers have been able to keep them alive for months in captivity in spite of the vast differences in temperature and pressure.

From: http://www.seasky.org/deep-sea/fangtooth.html

Deep Sea Dragonfish

The deep sea dragonfish, sometimes known as the scaleless dragonfish, is a ferocious predator that inhabits the deep oceans of the world. Known scientifically as Grammatostomias flagellibarba, it has extremely large teeth compared to its body size. In spite of its gruesome appearance, its is a small fish, measuring only about 6 inches (about 15 centimeters) in length. There are several different species of dragonfish. All are very similar in appearance.

The deep sea dragonfish is one of the many species of deep sea fish that can produce its own light through a chemical process known as bioluminescence. The light is produced by a special organ known as a photophore. It is believed that the fish can use these flashing lights in the dark waters to attract prey and even to signal potential mates. The dragonfish has a large head and mouth equipped with many sharp, fang-like teeth. It also has a long protrusion known as a barbel attached to its chin. This barbel is tipped with a light-producing photophore. 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.

The dragonfish can use its light-producing barbel like a fishing lure. By flashing it on and off and waving it back and forth, it is thought that the dragonfish can attract the attention of its potential meal. Once an unsuspecting fish gets too close, it is snapped up in the dragonfish's powerful jaws. The large teeth of the dragonfish help it to grab its prey as it hunts in the dark waters of the deep sea. It will feed on small fish and crustaceans as well as anything else it can find. Since many of their prey also produce light themselves, the dragonfish has evolved special method of remaining hidden from predators after its meal. The walls of its stomach are black to keep the lights concealed while its meal is digested.

Because they live in extremely deep waters, very little is known about the mating habits of the dragonfish. It is believed that they are external spawners, meaning that the female releases eggs into the water to be fertilized by the male. The eggs then float to the surface where they remain until hatching. Once the eggs hatch, the tiny larvae are left to fend for themselves until they can reach maturity. Once mature, they return to the deep ocean to spend the rest of their lives. Not much is known about the life span of the dragonfish.

The deep sea dragonfish lives in deep ocean waters at depths of up to 5,000 feet (1,500 meters). Although dragonfish species are found in most oceans the world, the deep sea dragonfish is limited mainly to the North and Western Atlantic Ocean and the Gulf of Mexico.

From: http://www.seasky.org/deep-sea/dragonfish.html

Deep Sea Anglerfish

The deep sea anglerfish is one of the most bizarre-looking fish in the sea. Known scientifically as Melanocetus johnsoni, it is also one of the best-known creatures of the deep. It is one of about 200 species of anglerfish found throughout the world's oceans. The angler gets its name from the elongated dorsal spine that supports a light-producing organ known as a photophore. Through a chemical process known as bioluminescence, this photophore can produce a blue-green light similar to that of a firefly on land. The fish uses this appendage like a fishing lure, waving it back and forth to attract its prey.

The deep sea anglerfish has a round body that resembles a basketball, and indeed, it looks like it could easily swallow one. It has a very large mouth with sharp, fang-like teeth. Its grotesque appearance has earned it the nickname "common black devil". Despite its ferocious appearance, the angler is a small fish, reaching a maximum length of only about five inches (12 centimeters). The color of this anglerfish ranges from brown to dark gray or black. It has soft flesh and bones and small eyes. Its skin is specially adapted to reflect blue light. Since nearly all light emitted from bioluminescent creatures is blue, the anglerfish can be nearly invisible to other deep sea animals. Due to its wide, round body, it cannot swim very fast. Instead, it somewhat "wobbles" through the water.

The anglerfish uses its illuminated lure as its hunts for prey. This specialized spine is highly maneuverable and can be moved in any direction. The anglerfish is known to remain completely motionless, waving its lure back and forth like a fishing pole. When the prey fish gets close enough, the angler snaps it up with its powerful jaws and swallows it whole. The sharp teeth of the angler are angled inwards, which helps to prevent the prey from escaping. The anglerfish can extend both its jaw and its stomach to an incredible size, allowing it to swallow prey twice the size of its entire body. Since food can be scarce in the deep sea, this special adaptation allows it to stock up on food during times of plenty.

The deep sea anglerfish has an extremely unusual method of reproduction. The male angler is much smaller than the female and completely different in appearance. It is about the size of a small finger and black in color. When a male angler matures, its digestive system degenerates, making it impossible for it to feed on its own. It must now find a female or die of starvation. The male angler has small hook teeth, which it uses to attach itself to the female. Once he bites into her skin, he releases an enzyme that dissolves the skin of his mouth and that of her body. The two become fused together and their blood vessels join as one. The male will spend the rest of its life joined to the female like a parasite, getting all of his nourishment from her body. A female can carry up to six males on her body at a time. This bizarre method of reproduction helps to ensure that when the female is ready to spawn, she has a mate instantly available. The female will lay her eggs in a thin sheet of gelatinous material two or three feet (about one meter) wide and about 30 feet (9 meters) long. This thin sheet of eggs floats free in the sea until the eggs hatch into tiny larvae. Once hatched, the larvae swim to the surface and feed on plankton. As they mature, they return to the depths below.

The deep sea angler is found throughout the world's oceans at depths of over 3,000 feet (914 meters). At this depth, there is almost no light and the water is near freezing. Many species of anglerfish are fished commercially throughout the world. They are compared to lobster in taste and texture. In Japan, anglerfish is considered a delicacy and can fetch a premium price.

From: http://www.seasky.org/deep-sea/anglerfish.html

Chambered Nautilus

The curious-looking chambered nautilus, also known simply as the nautilus, is considered by many to be a living fossil. Nautilus pompilius is the largest and most common of about six species known to exist. Like the coelacanth, it has remained unchanged for over 400 million years. During prehistoric times, there were about 10,000 different species of nautilus, but only a small handful are known to survive today. The nautilus is a mollusk and a member of the cephalopod family. It is closely related to other cephalopods such as the squid, cuttlefish, and octopus. Like most cephalopods, it can use jet propulsion to attain speeds of over two knots. A small tube near the animal's tentacles, known as a siphon, expels water under pressure. This propels the nautilus in the opposite direction at high speeds.

The life and habits of the nautilus are still largely a mystery, since it spends most of its time in deep water. The shell of the nautilus is comprised of many individual chambers. Each chamber is individually sealed and contains an amount of gas. This provides the animal with buoyancy. The nautilus can regulate its density by injecting or removing fluid into these chambers through a system of tubes. This strong shell also provides protection for the animal's soft body. The nautilus has many more tentacles than its close cousins. Depending on the particular species, there can be up to 90 separate tentacles. The tentacles are arranged into two circles, and unlike those of other cephalopods, they have no suction cups. These tentacles are used to catch shrimp, fish and small crustaceans, which the animal crushes with its powerful beak. Nautiluses are active predators, but since their siphon system uses very little energy while swimming, they only need to eat about once a month. Their eyesight is very poor because their eyes contains no lenses. Instead, there is only a tiny hole to allow light into the eye. This system operates much like a pinhole camera. The nautilus is thought to rely mainly on its sense of smell when searching for food or looking for a mate. An adult nautilus can grow to about eight inches (20 centimeters) in length.

The Nautilus reproduces by laying eggs. The eggs are usually attached to rocks in shallow water, hidden away from curious predators. These eggs require between eight and twelve months to fully develop. When a young nautilus first hatches from its egg, it is about an inch in diameter and has a shell with seven chambers. The young animal will drift and feed on plankton and other small prey as it grows. As it gets larger, it will add new chambers to its shell. Each new chamber will be a little larger that the last, allowing the opening of the shell to continually grow larger. The average life span of the nautilus is believed to be about 20 years, which is unusually long for a member of the cephalopod family.

Nautiluses are found throughout the Pacific and Indian oceans, where they spend their daylight hours at depths of about 1,800 feet (550 meters). At night they migrate to shallower waters to feed among the coral reefs. The shell of the nautilus cannot withstand the pressure of depths greater than 2,600 feet (800 meters). Unfortunately, nautilus populations are on the decline due to the harvesting of their beautiful shells. Because of this, export of the shells has been banned in may countries throughout the world. You can help save this amazing animal by refusing to buy nautilus shells.

From: http://www.seasky.org/deep-sea/chambered-nautilus.html

Coelacanth

The strange-looking coelacanth is one of the oldest species of fish in the world. It is considered by many to be an actual living fossil. Known scientifically as Latimeria chalumnae, this fish was thought to have been extinct since the end of the cretaceous period over 65 million years ago. Fossils of the coelacanth have been found that date back over 350 million years. But, against all odds, in 1938, a fisherman actually caught a live coelacanth off the coast of South Africa. A second specimen was captured in 1952 off the coast of the Comoros Islands off theeastern coast of Africa near Madagascar. Needless to say, this caused a sensation throughout the scientific community. Since then, live coelacanths have been sighted and photographed many times in the wild.

The coelacanth is closely related to the lungfishes and tetrapods, ancient animals that form part of the evolutionary bridge between sea creatures and land dwellers. The long fins of the coelacanth actually contain bones that resemble toes divided into three lobes. Because of this, it is referred to as a lobe-finned fish. These leg-like fins have earned this fish the nickname, "old fourlegs". Another prehistoric feature of this unique fish are its scales. These highly modified scales are known as cosmoid scales, and are only found on extinct fish species. They are woven tight like armor and are rough to the touch. These hard scales help protect the fish from rocks and predators. Coelacanths are large fish, growing to average length of 6.5 feet (2 meters). They can weigh as much as 175 pounds (80 kg). In the wild, they have a deep blue color which is thought to help camoflauge them from predators. The eyes of the coelacanth are extremely sensitive to light. They contain a special adaptation known as a tapetum, which is also found in cats, dogs, and dolphins. It is the tapetum that causes a cat's eyes to glow when exposed to bright light. This highly specialized eye enables the coelacanth to see as much as possible in the lightless environments of the deep sea.

Ceolacanths are opportunistic feeders, eating just about anything they can find and fit in their mouth. They possess hinges in their skulls that allow them to consume very large prey. Their diet is believed to consist mainly of squid, eels, small sharks, and other animals that are found in their deep sea habitats. They hunt their prey near deep underwater volcanic slopes and can frequently be seen swimming with their heads down. They have even been seen swimming upside down and backwards. Researchers believe that this behavior allows them to use a special organ called a rostral gland to help them locate their prey. Once located, their meal is usually swallowed whole. Since food can be scarce at these great depths, scientists believe that the coelacanth has the ability to slow down its metabolism. This allows the fish to go for long periods of time without eating. This may be part of the reason they have survived so long and outlived their other prehistoric cousins. In their natural habitat, they are believed to live about 60 years.

Coelacanths give birth to live young, known as "pups". There are usually between 5 and 25 pups born at any given time. These young coelacanth pups are fully formed and capable of surviving on their own as soon as they are born. Their gestation time is 13 months, and it is believed that ceolacanths are unable to reproduce until they are 20 years old. Beyond that, very little is known about the reproductive habits of this elusive creature

Coelacanths can be found throughout the Indian ocean, from the southwest coast of Africa to Indonesia. They can to go as deep as 2,300 feet (700 meters), but are more commonly found at a depth of 300 - 600 feet (90 - 200 meters). Because of their sensitive eyes, these fish prefer the darkness. They are rarely ever seen during the daytime hours or on nights with a full moon. They prefer cold water because their gills have trouble absorbing oxygen in warm water. In Sodwana Bay, South Africa, coelacanths have been found resting in caves during the day.

In 1989, the coelacanth was declared an endangered species by the international community. Their current world population is believed to be fewer than 500 animals. This means that without protection, this prehistoric animal that has survived for over 350 million years could be wiped out in our lifetime.

From: http://www.seasky.org/deep-sea/coelacanth.html

Footballfish

The footballfish are a family, Himantolophidae, of globose, deep-sea anglerfishes found in tropical and subtropical waters of the Atlantic, Indian, and Pacific Ocean. As in other deep-sea anglerfish families, sexual dimorphism is extreme: the largest females may exceed lengths of 60 cm (two feet) and are globose in shape, whereas males do not exceed 4 cm (1.5 inches) as adults and are comparatively fusiform. Both are a reddish brown to black in life.

In both sexes, the fins are spineless: the single dorsal fin with 5 – 6 soft rays, the pectoral fins with 14 – 18, the anal fin with four, and the caudal fin with 19. There are six branchiostegal rays and 19 vertebrae; the parietal is lacking throughout life, there are no epurals, and the pelvic bone is triradiate.  

The football fish was first discovered in the early 1900s by deep sea fisherman in search of flounder.Their poor musculature and cumbersome morphology indicate that female footballfish at least are probably poor swimmers and largely sedentary, lie-in-wait predators. They are primarily mesopelagic, living in open water, with very few caught below 1,000 m (3,280 ft). Females are carnivorous and feed upon other pelagic fish (such as lanternfishes and ridgeheads) and cephalopods, as well as shrimp and euphausiids. Upon maturity, the tiny males of most species metamorphose into a parasitic form, which lacks both a lure and true teeth and is presumed not to feed. The parasitic males use their enlarged olfactory bulbs (as indicated by their enlarged nostrils) and sensitive eyes to home in on the pheromones and possibly the species-specific lures of mature females, as is the case in other ceratioid anglerfish families.

Footballfish are presumed to be non-guarders and to spawn pelagically. Their larvae are epipelagic (occurring in the well-lit 200 m of the water column), indicating they probably undergo an ontogenetic descent into deeper waters as the larvae mature. Predators of footballfish include Sperm Whales and other footballfish. 

Humans do not use the fish, but scientists are attempting to use the shape of the fish to advance deep sea exploration.

From: http://en.wikipedia.org/wiki/Footballfish

Atlantic Hagfish

The Atlantic hagfish, scientifically known as Myxine glutinosa, is an unusual sea creature. Its body is covered with special glands that can emit a sticky slime. In fact, a single hagfish can produce enough slime at one time to fill a milk jug. This has earned it the name "slime eel", although it is really not an eel at all. A hagfish will actually "sneeze" when its own nostrils fill with slime. Hagfish slime is different that any other natural slime secretion in that it is reinforced with tiny fibers. These fibers make the slime strong and difficult to remove. It is believed that the hagfish uses this slime to protect itself from predators. It can also be used to easily produce a protective cocoon for the hagfish. It is believed that this slime can actually suffocate predators by clogging their gills if they come in contact with it. The hagfish has a trick for escaping this slime cocoon. Believe it or not, this animal can tie itself in a knot and then pass the knot down the length of its body to wipe the slime away.

The Atlantic hagfish has been called the nastiest and most disgusting little creature in the sea. Over 60 different species are known to science. There is actually some debate among researchers as to whether the hagfish is really a fish. It is more closely related to some primitive creatures such as the lampreys. Hagfish have a long, eel-like body that averages 18 inches (about a half meter) in length, although it is believed that some of them can grow as long as 32 inches (nearly a meter). The hagfish is a scaleless fish with soft skin and thick barbels on the end of its mouth. Hagfish have a partial skull but no vertebrae, so they cannot technically be classified as vertebrates. They have no jaws and no bones. Their skeleton is made up entirely of cartilage. They have very poorly developed eyes located just under the skin and are almost blind. They do, however have finely developed senses of smell and touch which help them find food in the darkness of the deep sea. There are four small sensing tentacles near their mouth. They also have between 5 and 15 pairs of gills. Their colors can range from pink to brown to various shades of gray. Hagfish have a very primitive circulatory system that contains four hearts. One heart, known as the brachial heart, serves as the main pump, while the other three hearts serve as accessory pumps.

Lamprey

The hagfish is a true monster of the deep. To see why, one only has to examine its greusome feeding habits. A hagfish begins its feeding process by attaching itself to a passing fish. Once firmly attached, it then bores its way inside its unsuspecting host. Once inside, the hagfish will actually eat the fish's flesh with a specialized rasping tongue. It literally eats its victim from the inside out. When no large prey can be found, hagfish will feed on worms and other small invertebrates they find on the ocean floor. Hagfish have a very slow metabolism and can go for months without feeding.

Very little is known about the reproductive habits of the hagfish. It has been observed that some hagfish species are actually hermaphroditic, which means that they are both male and female. Females will lay up to 30 tough, yolky eggs. These eggs tend to stick together due to velcro-like attachments on the ends. Hagfish are often found curled around their eggs, but it is not know if they actually take care of the eggs with any type of brooding behavior. Hagfish do not go through a larval stage like their cousins, the lampreys. The newly hatched young are nearly perfect miniatures of their parents. The are all born hermaphroditic, but will change to either male or female as they develop. That have the ability to change sexes from season to season. Since local populations of hagfish tend to be quite large, as many as 15,000, it is believed that they have a low mortality rate.

The Atlantic hagfish is a deep-water fish. They can be found at depths of up to 5,600 feet (about 1,800 meters). They are known on both sides of the North Atlantic Ocean as far north as Norway. Hagfish prefer soft sea bottoms where they can quickly bury themselves when threatened.


From: http://www.seasky.org/deep-sea/atlantic-hagfish.html