The Pacific viperfishChauliodus macouni, is a predatory fish that lives in the abyssal depths of the deep sea. In daytime it can be found from 200–5000 m below the ocean surface. At night it swims up into shallower depths of less than 200m where food is more plentiful. Pacific viperfish will mostly eat crustaceans and small fish. They typically reach lengths of up to 1 foot and are considered an example of deep-sea gigantism.According to O’Day (1973) luminescent silhouetting may aid the fish in mating, spacing themselves out as they hunt, maintaining conspecific aggregations, warning potential predators of their own formidable size, or perhaps allowing them to escape from predators by temporarily blinding them. These functions, however, remain speculative.Pacific viperfish can be characterized by its large mouth, long fang-like teeth and long dorsal fin ray (as much as half its body length). They are iridescent dark silver-blue color in life with pale fins. They can also be a light black color with blue fins.As most fish species, the Pacific viperfish has several parasites. In 2018, Susumu Ohtsuka, Dhugal J. Lindsay and Kunihiko Izawa described a new genus and species of pennellid copepodProtosarcotretes nishikawai, from a single ovigerous female infecting a Pacific viperfish collected from the deep-waters of Suruga Bay, Japan. According to the authors, the new genus had the most plesiomorphic states in the first to fourth legs of pennellid copepods.



Fangtooths are beryciform fish of the family Anoplogastridae (sometimes spelled “Anoplogasteridae”) that live in the deep sea. The name is from Greek anoplo meaning “unarmed” and gaster meaning “stomach”. With a circumglobal distribution in tropical and cold-temperate waters, the family contains only two very similar species in one genus, with no known close relatives.While understandably named for their disproportionately large, fang-like teeth and unapproachable visage, fangtooths are actually quite small and harmless to humans: the larger of the two species, the common fangtooth, reaches a maximum length of just 16 cm (6.3 in);[2] the shorthorn fangtooth is less than half this size[3] though currently known only from juvenile specimens.The head is small with a large jaw and appears haggard, riddled with mucous cavities delineated by serrated edges and covered by a thin skin. The eyes are relatively small, set high on the head; the entire head is a dark brown to black and is strongly compressed laterally, deep anteriorly and progressively more slender towards the tail. The fins are small, simple, and spineless; the scales are embedded in the skin and take the form of thin plates. As compensation for reduced eyes, the lateral line is well-developed and appears as an open groove along the flanks.In adults, the largest two fangs of the lower jaw are so long, the fangtooths have evolved a pair of opposing sockets on either side of the brain to accommodate the teeth when the mouth is closed. According to BBC’s Blue Planet, episode “The Deep”, the fangtooth has the largest teeth of any fish in the ocean, proportionate to body size, and are so large, they can never close their mouths. The juveniles are morphologically quite different – unlike the adults, they possess long spines on the head and preoperculum, larger eyes, a functional gas bladder, long and slender gill rakers, much smaller and depressible teeth, and are a light gray in colour. These differences once caused the two life stages to be classed as distinct species, with one in another genusCaulolepis.The pelagic fangtooths are among the deepest-living fish, found as far as 5,000 m (16,000 ft) down.[1] They are more commonly found between 200 and 2,000 m (660 and 6,560 ft), however, and juveniles apparently stay within the upper reaches of this range. They may undergo diel migrations as is common with many deep-sea fish: by day these fish remain in the gloomy depths and towards evening they rise to the upper layers of the water column to feed by starlight, returning to deep water by daybreak. Fangtooths may form small schools or go alone. They are thought to use contact chemoreception to find prey, relying on luck to bump into something edible.The smaller teeth and longer gill rakers of juveniles suggest they feed primarily by filtering zooplankton from the water, while the deeper-living adults target other fish and squid. The fangtooths’ oversized teeth and mouths are a common feature among the miniature beasts of the deep (cf. viperfishesdaggertoothsbristlemouthsbarracudinasanglerfishes), thought to be an advantage in these lean waters where anything encountered (even if it is larger than the fish) must be considered a possible meal. The fangtooths in turn are preyed upon by other large pelagic fish, such as tuna and marlin and some species of sharks.Fangtooths are known to be robust when compared to many other deep-sea fish;[5] they have been kept alive for months in aquariums despite conditions which are significantly different from their usual deep-sea habitat.Fangtooths have planktonic larvae and are assumed to not be egg guarders; spawning frequency and time are not certain, but some activity has been reported from June–August. The juveniles of common fangtooths begin to assume adult form from about 8 cm (3.1 in) in length, at which time they begin to descend into deeper water.[8] Onset of maturity is not known, but common fangtooths are known to be mature at 16 cm (6.3 in). They are probably slow-growing, as are most deep-sea fish.


The Atlantic wolffish (Anarhichas lupus), also known as the seawolfAtlantic catfishocean catfishdevil fishwolf eel (the common name for its Pacific relative), woof or sea cat, is a marine fish of the wolffish family Anarhichadidae. The numbers of the Atlantic wolffish in US waters are rapidly being depleted, most likely due to overfishing and bycatch, and is currently a Species of Concern according to the U.S. National Oceanic and Atmospheric Administration‘s National Marine Fisheries Service. Apart from their unique appearance wolffish are distinguished by the natural antifreeze they produce to keep their blood moving fluidly in their very cold habitat, involvement by both the male and female in brood bearing, and the large size of their eggs. They are also an important factor in controlling green crab and sea urchin populations, which can become overly disruptive to habitats if left unchecked. Wolffish population success is also an important indicator of the health of other bottom-dweller populations, such as Atlantic cod. The Atlantic wolffish has retained the bodily form and general external characteristics of small blennies (Blennioidei). The largest specimen recorded measured 1.5 m (5 ft) long and weighed almost 18 kg (40 lb).[3] Its body is long, subcylindrical in front, compressed in the caudal portion, smooth and slippery, the rudimentary scales being embedded and almost hidden in the skin. Atlantic wolffish vary in color, usually seen as purplish-brown, a dull olive green, or blueish gray.[2] An even dorsal fin extends the whole length of the back, and a similar fin from the vent to the caudal fin, as in blennies. The pectorals are large and rounded and the pelvic fins are entirely absent. Its obtuse, eel-like body type makes the fish swim slowly, undulating from side to side, like an eel. The Atlantic wolffish’s distinguishing feature, from which it gets its common name, is its extensive teeth structure. Its dentition distinguishes the Atlantic wolffish from all the other members of the family Anarhichadidae. Both the lower and upper jaws are armed with four to six fang-like, strong, conical teeth. Behind the conical teeth in the upper jaw, there are three rows of crushing teeth. The central row has four pairs of molars and the outer rows house blunted conical teeth. The lower jaw has two rows of molars behind the primary conical teeth. The wolffish’s throat is also scattered with serrated teeth.Atlantic wolffish inhabit both the west and east coasts of the Atlantic. In the west Atlantic, they are seen as far north as the Davis Strait, of the Canadian territory of Nunavut, populating the shores of GreenlandNewfoundland, and Nova Scotia, extending as far south as Cape Cod. Although they are seldom seen south of Cape Cod, there have been sightings in New Jersey. The most dense populations are in Georges Bank, the Gulf of Maine and the Great South Channel.[4] In the eastern Atlantic, they range from Russia’s White Sea and Novaya Zemlya, through the Nordic countries and British Isles, to the Bay of Biscay. Atlantic wolffish are primarily stationary fish, rarely moving from their rocky homes. They are benthic dwellers, living on the hard ocean floor, frequently seen in nooks and small caves. They like cold water, at depths of 20 to 500 m (66–1,640 ft).[5] They are usually found in water temperatures of −1 to 11 °C (30–52 °F). Since they can live in near-freezing waters (salt water only freezes at slightly below 0 °C or 32 °F), to keep their blood moving smoothly, they contain a natural antifreeze. Three related species (Atlantic, northern and spotted wolffish) occur in the north Atlantic.[5] The northern wolffish has loose gelatinous flesh, but the other species are esteemed as food, both fresh and preserved.[5] They are marketed in Britain as “Scotch halibut” and “Scarborough woof”, or, simply “woof” in other areas of the northeast coast, and are a popular ingredient in fish and chips.


The eagle rays are a group of cartilaginous fishes in the family Myliobatidae, consisting mostly of large species living in the open ocean rather than on the sea bottom.Eagle rays feed on mollusks and crustaceans, crushing their shells with their flattened teeth. Devil and manta rays filter plankton from the water. They are excellent swimmers and are able to breach the water up to several metres above the surface. Compared with other rays, they have long tails, and well-defined, rhomboidal bodies. They are ovoviviparous, giving birth to up to six young at a time. They range from 0.48 to 9.1 m (1.6 to 29.9 ft) in length.Nelson’s book Fishes of the World treats cownose rays, mantas, and devil rays as subfamilies in the Myliobatidae. However, most authors (including William Toby White) have preferred to leave the Rhinopteridae and Mobulidae outside of the Myliobatidae.[2] White (2014) retained three genera (AetobatusAetomylaeus, and Myliobatis) in the Myliobatidae, while a fourth (Pteromylaeus) was synoymized with Aetomylaeus.[2] A 2016 paper placed Aetobatus in its own family, the Aetobatidae.This obscure genus is distributed in the Eastern Atlantic OceanIndian Ocean, and Pacific Ocean. These rays were named because they lack a sting on the tail.The common eagle rayM. aquila, is distributed throughout the Eastern Atlantic, including the Mediterranean Sea and the North Sea. Another important species is the bat eagle rayM. californica, in the Pacific Ocean. These rays can grow extremely large, up to 1.8 m (6 ft) including the tail. The tail looks like a whip and may be as long as the body, and is armed with a sting. Eagle rays live close to the coast in depths of 1 to 30 m (3 to 98 ft) and in exceptional cases they are found as deep as 300 m (980 ft). The eagle ray is most commonly seen cruising along sandy beaches in very shallow waters, its two wings sometimes breaking the surface and giving the impression of two sharks traveling together.Eagle rays unlike stingrays tend to live in the open ocean rather than on the bottom of the sea. Compared with other rays, their tails are quite long and they are a well-defined rhomboidal shape featuring distinct wings.


The bluespotted ribbontail ray (Taeniura lymma) is a species of stingray in the family Dasyatidae. Found from the intertidal zone to a depth of 30 m (100 ft), this species is common throughout the tropical Indian and western Pacific Oceans in nearshorecoral reef-associated habitats. It is a fairly small ray, not exceeding 35 cm (14 in) in width, with a mostly smooth, oval pectoral fin disc, large protruding eyes, and a relatively short and thick tail with a deep fin fold underneath. It can be easily identified by its striking color pattern of many electric blue spots on a yellowish background, with a pair of blue stripes on the tail.At night, small groups of bluespotted ribbontail rays follow the rising tide onto sandy flats to root for small benthic invertebrates and bony fishes in the sediment. When the tide recedes, the rays separate and withdraw to shelters on the reef. Reproduction is aplacental viviparous, with females giving birth to litters of up to seven young. This ray is capable of injuring humans with its venomous tail spines, though it prefers to flee if threatened. Because of its beauty and size, the bluespotted ribbontail ray is popular with private aquarists despite being poorly suited to captivity. The International Union for Conservation of Nature (IUCN) has listed this species as Near Threatened, as it faces widespread habitat degradation and intensive fishing pressure throughout its range.he bluespotted ribbontail ray was originally described as Raja lymma by Swedish naturalist Peter Forsskål, in his 1775 Descriptiones Animalium quae in itinere ad maris australis terras per annos 1772, 1773, et 1774 suscepto collegit, observavit, et delineavit Joannes Reinlioldus Forster, etc., curante Henrico Lichtenstein.[2] The specific epithet lymma means “dirt”.[3] Forsskål did not designate a type specimen.[2] In 1837, German biologists Johannes Peter Müller and Friedrich Gustav Jakob Henle created the genus Taeniura for Trygon ornatus, now known to be a junior synonym of this species. Other common names used for this species include bluespotted ray, bluespotted fantail ray, bluespotted lagoon ray, bluespotted stingray, fantail ray, lesser fantail ray, lagoon ray, reef ray, ribbon-tailed stingray, and ribbontail stingray.[5] Morphological examination has suggested that the bluespotted ribbontail ray is more closely related to the amphi-American Himantura (H. pacifica and H. schmardae) and the river stingrays (Potamotrygonidae) than to the congeneric blotched fantail ray (T. meyeni), which is closer to Dasyatis and Indo-Pacific Himantura.Widespread in the nearshore waters of the tropical Indo-Pacific region, the bluespotted ribbontail ray has a range that extends around the periphery of the Indian Ocean from South Africa to the Arabian Peninsula to Southeast Asia, including MadagascarMauritiusZanzibar, the SeychellesSri Lanka, and the Maldives. It is rare in the Persian Gulf and Gulf of Oman. In the Pacific Ocean, this species is found from the Philippines to northern Australia, as well as around numerous Melanesian and Polynesian islands as far east as the Solomon Islands.[1] Rarely found deeper than 30 m (100 ft), the bluespotted ribbontail ray is a bottom-dwelling species that frequents coral reefs and adjacent sandy flats. It is also commonly encountered in the intertidal zone and tidal pools, and has been sighted near seagrass beds.


Stingrays are a group of sea rays, which are cartilaginous fish related to sharks. Many species are endangered. They are classified in the suborder Myliobatoidei of the order Myliobatiformes and consist of eight families: Hexatrygonidae (sixgill stingray), Plesiobatidae (deepwater stingray), Urolophidae (stingarees), Urotrygonidae (round rays), Dasyatidae (whiptail stingrays), Potamotrygonidae (river stingrays), Gymnuridae (butterfly rays), and Myliobatidae (eagle rays).[1][2]Stingrays are common in coastal tropical and subtropical marine waters throughout the world. Some species, such as Dasyatis thetidis, are found in warmer temperate oceans, and others, such as Plesiobatis daviesi, are found in the deep ocean. The river stingrays, and a number of whiptail stingrays (such as the Niger stingray), are restricted to fresh water. Most myliobatoids are demersal (inhabiting the next-to-lowest zone in the water column), but some, such as the pelagic stingray and the eagle rays, are pelagic.[3]There are about 220 known stingray species organized into 10 families and 29 genera. Stingray species are progressively becoming threatened or vulnerable to extinction, particularly as the consequence of unregulated fishing.[4] As of 2013, 45 species have been listed as vulnerable or endangered by the IUCN. The status of some other species is poorly known, leading to their being listed as data deficient.The mouth of the stingray is located on the ventral side of the vertebrate. Stringrays exhibit euhyostyly jaw suspension, which means that the mandibular arch is only suspended by an articulation with the hyomandibula. This type of suspensions allows for the upper jaw to have high mobility and protrude outward.[6] The teeth are modified placoid scales that are regularly shed and replaced.[7] In general, the teeth have a root implanted within the connective tissue and a visible portion of the tooth, is large and flat, allowing them to crush the bodies of hard shelled prey.[8] Male stingrays display sexual dimorphism by developing cusp, or pointed ends, to some of their teeth. During mating season, some stingray species fully change their tooth morphology which then returns to baseline during non-mating seasons.Stingrays can breathe through their spiracles, which are openings just behind their eyes. The respiratory system of stingrays is complicated by having two separate ways to take in water to utilize the oxygen. Most of the time stingrays take in water using their mouth and then send the water through the gills for gas exchange. This is efficient, but the mouth cannot be used when hunting because the stingrays bury themselves in the ocean sediment and wait for prey to swim by.[10] So the stingray switches to using its spiracles. With the spiracles, they can draw water free from sediment directly into their gills for gas exchange.[11] These alternate ventilation organs are less efficient than the mouth, since spiracles are unable to pull the same volume of water. However, it is enough when the stingray is quietly waiting to ambush its prey.The flattened bodies of stingrays allow them to effectively conceal themselves in their environments. Stingrays do this by agitating the sand and hiding beneath it. Because their eyes are on top of their bodies and their mouths on the undersides, stingrays cannot see their prey after capture; instead, they use smell and electroreceptors (ampullae of Lorenzini) similar to those of sharks.[12] Stingrays settle on the bottom while feeding, often leaving only their eyes and tails visible. Coral reefs are favorite feeding grounds and are usually shared with sharks during high tide.


The cownose ray (Rhinoptera bonasus) is a species of eagle ray found throughout a large part of the western Atlantic and Caribbean, from New England, United States to southern Brazil (East Atlantic populations are now generally considered a separate species, R. marginata); a separate sub-species is known on Australia (Rhinoptera neglecta Ogilby)[1]. Cownose rays grow rapidly, and male rays often reach about 35 inches (89 cm) in width and weigh 26 pounds (12 kg). Females typically reach 28 inches (71 cm) in width and weigh 36 pounds (16 kg). The cownose ray is classified as a stingray due to the very close relation to both sharks and skates. These rays also belong to the order Myliobatiformes, a group that is shared by bat rays, manta rays, and eagle rays.Cownose rays breed from June through October. A large school of cownose rays gather of varying ages and sexes in shallow waters. A female will swim with the edges of her pectoral fins sticking out of the water, with male cownose rays following her trying to grasp the fins to mate.[3]The embryo grows within its mother with its wings folded over its body. Initially it is nourished by an egg yolk, although the uterine secretions of the mother nourish it later in its development. The length of gestation is disputed, but it is believed to last between 11 and 12 months and is variable. At full term, the offspring are born live, exiting tail first.The cownose ray is 11 to 18 inches (28 to 46 cm) in width at birth. A mature specimen can grow to 45 inches (1.1 m) in width, and weigh 50 pounds (23 kg) or more. There is some controversy over the size that a mature cownose ray can reach. A ray reaching a span of 84 inches (2.1 m) has been recorded.[5] The cownose ray is often mistaken for being a shark by beach-goers. This is due to the tips of the rays fins sticking out of the water, often resembling the dorsal fin of a shark.A cownose ray is typically brown-backed with a whitish or yellowish belly. Although its coloration is not particularly distinctive, its shape is easily recognizable. It has a broad head with wide-set eyes, and a pair of distinctive lobes on its subrostral fin. It also has a set of dental plates designed for crushing clams and oyster shells. When threatened the cownose ray can use the barb at the base of its tail to defend itself from the threat.A cownose ray has a spine with a toxin, close to the ray’s body. This spine has teeth lining its lateral edges, and is coated with a weak venomthat causes symptoms similar to that of a bee sting.The cownose ray feeds upon clamsoystershard clams and other invertebrates. It uses two modified fins on its front side to produce suction, which allows it to draw food into its mouth, where it crushes its food with its dental plates. Cownose rays typically swim in groups, which allows them to use their synchronized wing flaps to stir up sediment and expose buried clams and oysters.


The jelly blubber (Catostylus mosaicus), also known as the blue blubber jellyfish, is a species of jellyfish from coastal regions in the Indo-Pacific. It is the most commonly encountered jellyfish along the Australian eastern coast and large swarms sometimes appear in estuarine waters.In Sydney waters, the jelly blubber’s large bell is a creamy white or brown colour, but farther north in Australia it is usually blue.[1] The colours are derived from pigment produced by the jellyfish itself (not symbiotic algae, as in some other jellyfish).[2] There is no obvious mouth on the underside, but there are small openings on each arm, through which food is passed to the stomach.[3] The tentacles also have stinging cells that can capture tiny crustaceans and other plankton. It grows to a diameter of 30–45 cm (12–18 in).The sting can be painful but generally poses no serious risk to humans.This jellyfish is found in coastal parts of the Indo-Pacific. In Australia, it occurs off the coasts of QueenslandNew South Wales and Victoria. It can also enter intertidal estuaries.Eats mainly plankton, small fish, some crustaceans, and small particles in the ocean water.Blue blubber jellyfish is a type of fish that can only be found at the Deep Sea Fishing Hub, which can be accessed by talking to Goomah in the Fishing Guild. Players need 91 Fishing to catch blue blubber jellyfish and a Cooking level of 95 to cook them.They stop burning at level 97 only if wearing cooking gauntlets, or while wearing the cooking cape at level 99. They give 235 Cooking experience per fish, which equals 394,800 experience per hour.The minimum Constitution level to receive the full amount of healing from this food is 30.Blue blubber jellyfish are consumed in 3 bites. Each bite heals a maximum of 750 life points. Eating blue blubber jellyfish does not reduce adrenaline, nor does it share a cool-down with many other foods and potions.


Sepia apama, also known as the giant cuttlefish and Australian giant cuttlefish,[3] is the world’s largest cuttlefish species, growing to 50 cm (20 in) in mantle length and over 10.5 kg (23 lb) in weight.[4][5] Using cells known as chromatophores, the cuttlefish can put on spectacular displays, changing color in an instant. S.apama is native to the southern coast of Australia, from Brisbane in Queensland to Shark Bay in Western Australia. It occurs on rocky reefs, seagrass beds, and sand and mud seafloor to a depth of 100 m.S. apama live 1–2 years. Breeding takes place with the onset of the southern winter. Males abandon their normal cryptic coloring and set out to dazzle the females by adopting rapidly changing bright colours and striking patterns. Females are polyandrous, and collaborative research indicates the tendency for females to reproduce using male genetic material deposited in spermatangia more favorably than in sperm receptacles directly. Females then attach their eggs to the undersides of rocks in caves or crevices, where they hatch within three to five months. S. apama is semelparous, and death follows shortly after a single mating cycle and laying of eggs that will spawn the next generation.[7] S. apama has poor anaerobic capability compared to most aquatic invertebrates and a lack of food leads to catabolism. Stomach-content analysis indicates fasting during the breeding season, and as S. apama can catabolise no more than 50% of its body weight, it slowly loses physical condition as the season progresses and eventually dies. Throughout their range, these squid breed in pairs or small groups, laying eggs in suitable caves or rock crevices. Loose spawning aggregations can form, but rarely exceed 10 animals in any one location,[8] with one known exception: hundreds of thousands aggregate along rockey reefs between Whyalla and Point Lowly in the Upper Spencer Gulf. While surveys suggest that juveniles leave these spawning grounds after hatching, nothing is known of their subsequent movement or lifestyle strategies as a juvenile. Adults return to the aggregation site the following winter, or delay their return by an additional year.Genetic studies have shown that little if any interbreeding occurs between S. apama populations. While some genetic divergence is seen, the various populations are not considered taxonomically distinct and are commonly referred to by their location, e.g. Sepia apama upper Spencer Gulf population.[7] The upper Spencer Gulf population is unique in that a permanent salinity gradient in the Spencer Gulf may physiologically exclude other populations from the zone occupied by the upper Spencer Gulf population.[7] The upper Spencer Gulf population may in fact be a separate species, as it does show some hallmarks, such as genetic separation, differences in morphology, and different patterns of sexual dimorphism from adjacent populations.[8][9]S. apama is a neritic demersal species. They are carnivorous, opportunistic and voracious predatorswho feed predominantly on crustaceans and fish.[8] Using neurally controlled cells known as chromatophore organs (red to yellow), iridophores (iridescent: spans the entire visible spectrum from blue to near-IR) and leucophores (white), the cuttlefish can put on spectacular displays, changing colour and patterns in a fraction of a second. Located in three layers under the skin, leucophores make up the bottom layer, with chromatophores the outermost. By selective blocking, the three layers work together to produce polarised patterns. Unlike those in most animals, cuttlefish iridophores are physiologically active; they can change their reflectivity, and the degree of polarisation can also be controlled. Cuttlefish are colourblind; however, the photoreceptors of cuttlefish eyes are arranged in a way which gives them the ability to see the linear polarisation of light. While the mantis shrimp is the only known creature to have true polarisation vision, cephalopods may also.[10] Because the optic lobes of cuttlefish are larger than any other region of the brain and their skin produces polarised reflective patterns, they may communicate through this visual system.[11] By raising elaborate papillae on their skin, S. apama squid can change the shape and the texture of their skin to imitate rock, sand, or seaweed.[12]bioenergetics study found that S. apama is primarily diurnal and has a small home range (90–550 m or 300–1,800 ft) over short recording periods while travelling large distances to breed. They are able to channel most of their energy directly into growth because they spend 95% of the day resting, suggesting bioenergetics more like that of an octopus than a squid. Very little time is spent foraging (3.7% during the day and 2.1% at night); most of their time is spent resting and hiding in crevices from predators. The exception to this behavioral routine is the mass spawning aggregation, where cuttlefish are far more active during the days or weeks that they spend there.


The lemon shark (Negaprion brevirostris) is a species of shark from the family Carcharhinidae. Lemon sharks can grow to 3.4 metres (11 ft) in length. They are often found in shallow subtropical waters and are known to inhabit and return to specific nursery sites for breeding. Often feeding at night, these sharks use electroreceptors to find their main source of prey: fish. Lemon sharks enjoy the many benefits of group living such as enhanced communication, courtshippredatory behavior, and protection. This species of shark gives birth to live young, and the females are polyandrous and have a biennial reproductive cycle. Lemon sharks are not thought to be a large threat to humans.The lemon shark was first named and described in 1868 by Felipe Poey.[3] He originally named it Hypoprion brevirostris, but later renamed it Negaprion brevirostris.[3] The lemon shark has also appeared in literature as Negaprion fronto and Carcharias fronto (Jordan and Gilbert, 1882), Carcharias brevirostris (Gunther, 1870), and Carcharhinus brevirostris (Henshall, 1891).The shark’s yellow colouring serves as a perfect camouflage when swimming over the sandy seafloor in its coastal habitat.[4] The lemon shark commonly attains a length of 2.4 to 3.1 m (7.9 to 10.2 ft) and a weight up to 90 kg (200 lb) by adulthood, although sexual maturity is attained at 2.24 m (7.3 ft) in males and 2.4 m (7.9 ft) in females.[5] The maximum recorded length and weight is 3.43 m (11.3 ft) and 183.7 kg (405 lb), respectively.[6] It has a flattened head with a short, broad snout, and the second dorsal fin is almost as large as the first. Lemon sharks have electroreceptors concentrated in their heads, called the ampullae of Lorenzini.[7] These receptors detect electrical pulses emitted by potential prey and allow these nocturnal feeders to sense their prey in the dark.Lemon sharks are found from New Jersey to southern Brazil in the tropical western Atlantic Ocean. They also live off the coast of west Africa in the southeastern Atlantic.[8] In addition, lemon sharks have been found in the eastern Pacific, from southern Baja California to Ecuador.[8] This species of shark often occupies the subtropical shallow waters of coral reefsmangroves, enclosed bays, and river mouths; however, lemon sharks have also been found in the open ocean down to depths of 92 meters (301 feet.)[9] Although lemon sharks do swim up rivers, they never seem to travel very far into fresh water. They are found in open water primarily during migrations, and tend to stay along the continental and insular shelves for most of their lives.The environmental temperature influences an individual’s body temperature, which ultimately affects physiological processes such as growth and metabolism.[11] Lemon sharks, therefore, select warm-water habitats to maintain optimal metabolic levels. They are believed to avoid areas with thick sea grasses because they make finding prey more difficult.[11] Lemon sharks tend to live in or near shallow-water mangroves, which are often the nursery areas of several species of fish. One theory is that lemon sharks select mangrove habitats due to the abundance of prey that resides there, while another theory posits that mangroves provide a safe haven from adult lemon sharks that occasionally feed on juvenile sharks and are unable to enter the shallow waters.[12] Ontogenetic niche shifts, or changes in an animal’s niche breadth or position, to deeper waters are known to occur in relation to a lemon shark’s size. These changes occur due to the dramatic decrease in the risk of predation as body size increases.[11] Habitat selection clearly depends on a variety of biological and environmental variables.Lemon sharks feed at night and are mainly piscivorous; however, they have been known to feed on crustaceans and benthic organisms.[15] Intraspecific predation, or cannibalism, of juvenile lemon sharks by larger conspecifics has also been documented.[11] Rather than feeding randomly, lemon sharks display a high degree of preference for certain species and size of prey when environmental conditions are favorable.[16] They also tend to prefer a prey when it is more abundant and available. Lemon sharks feed selectively on species that are slower and more easily captured by using a stalking technique.[17] For example, parrotfish and mojarras are common prey in the Bahamas because they use camouflage rather than an escape response and are vulnerable due to their stationary foraging behavior.