The bowfin (Amia calva) is a bony fish, native to North America. Common names include mudfish, mud pike, dogfish, grindle, grinnel, swamp trout, and choupique. It is regarded as a relict, being one of only two surviving species of the Halecomorphi, a group of fish that first appeared during the Early Triassic, around 250 million years ago. The bowfin is often considered a "primitive fish" because they have retained some morphological characteristics of their early ancestors. It is one of two species in the genus Amia, along with Amia ocellicauda, the eyespot bowfin. The closest living relatives of bowfins are gars, with the two groups being united in the clade Holostei.
Bowfins are demersal freshwater piscivores, commonly found throughout much of the eastern United States, and in southern Ontario and Quebec. Fossil deposits indicate Amiiformes were once widespread in both freshwater and marine environments across North and South America, Europe, Asia, and Africa. Now, their range is limited to much of the eastern United States and adjacent southern Canada, including the drainage basins of the Mississippi River, Great Lakes, and various rivers exiting in the Eastern Seaboard or Gulf of Mexico. Their preferred habitat includes vegetated sloughs, lowland rivers and lakes, swamps, and backwater areas; they are also occasionally found in brackish water. They are stalking, ambush predators known to move into the shallows at night to prey on fish and aquatic invertebrates such as crawfish, mollusks, and aquatic insects. (Full article...)
One of the largest sharks of its time, Cardabiodon has been estimated to measure up to 5.5 metres (18 ft) in length. It may have been an apex predator in its ecosystem and likely used its large, robust teeth and fast swimming capabilities to prey on a variety of marine animals including plesiosaurs, ichthyosaurs, and other large fish. Cardabiodon also had a very heavy and stocky body. Scientists have been partially successful in calculating the life history of the shark. At birth, Cardabiodon individuals measured between 41–76 centimetres (16–30 in) in length and reached sexual maturity at around five to seven years of age, but no conclusive estimates on the maximum lifespan of Cardabiodon have been made. (Full article...)
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The smooth hammerhead (Sphyrna zygaena) is a species of hammerhead shark, and part of the family Sphyrnidae. This species is named "smooth hammerhead" because of the distinctive shape of the head, which is flattened and laterally extended into a hammer shape (called the "cephalofoil"), without an indentation in the middle of the front margin (hence "smooth"). Unlike other hammerheads, this species prefers temperate waters and occurs worldwide at medium latitudes. In the summer, these sharks migrate towards the poles following cool water masses, sometimes forming schools numbering in the hundreds to thousands.
The second-largest hammerhead shark after the great hammerhead shark, the smooth hammerhead can measure up to 5 m (16 ft) long. It is an active predator that takes a wide variety of bony fishes and invertebrates, with larger individuals also feeding on sharks and rays. As in the rest of its family, this shark is viviparous and gives birth to litters of 20–40 pups. A relatively common shark, it is captured, intentionally or otherwise, by many commercial fisheries throughout its range; its fins are extremely valuable for use in shark fin soup. This shark is potentially dangerous and has likely been responsible for a few attacks on humans, though it is less likely to encounter swimmers than other large hammerhead species due to its temperate habitat. (Full article...)
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The blackmouth catshark (Galeus melastomus) is a species of catshark, and part of the familyScyliorhinidae, common in the northeastern Atlantic Ocean from Iceland to Senegal, including the Mediterranean Sea. It is typically found over the continental slope at depths of 150–1,400 m (490–4,590 ft), on or near muddy bottoms. The youngest sharks generally inhabit shallower water than the older juveniles and adults. This slim-bodied species is characterized by the black interior of its mouth, a marbled pattern of pale-edged brownish saddles or blotches along its back and tail, and a prominent saw-toothed crest of enlarged dermal denticles along the upper edge of its caudal fin. It reaches lengths of 50–79 cm (20–31 in), with sharks in the Atlantic growing larger than those in the Mediterranean.
Slow-swimming but active, the blackmouth catshark is a generalist that preys on a wide variety of crustaceans, cephalopods, and fishes. Its visual and electroreceptive systems are adept at tracking moving, bioluminescent prey. This species is oviparous, with females producing batches of up to 13 egg cases throughout the year. Because of its abundance, the blackmouth catshark forms a substantial part of the bycatch of deepwater commercial fisheries across much of its range. It has low economic value and is usually discarded, though the largest sharks may be marketed for meat and leather. The International Union for Conservation of Nature (IUCN) has listed this species under Least Concern, as there is no indication that its numbers have declined despite fishing pressure. (Full article...)
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Roughtail stingray (Bathytoshia centroura) at McGrail Bank, Gulf of Mexico
The roughtail stingray (Bathytoshia centroura) is a species of stingray in the familyDasyatidae, with separate populations in coastal waters of the northwestern and southwestern Atlantic Ocean. This bottom-dwelling species typically inhabits sandy or muddy areas with patches of invertebrate cover, at a depth of 15–50 m (49–164 ft). It is seasonally migratory, overwintering in offshore waters and moving into coastal habitats for summer. The largest whip-tail stingray in the Atlantic, the roughtail stingray grows up to 2.6 m (8.5 ft) across and 360 kg (800 lb) in weight. It is plain in color, with an angular, diamond-shaped pectoral fin disc and a long, whip-like tail bearing a subtle fin fold underneath. The many thorns on its back and tail serve to distinguish it from other stingrays that share its range.
The Atlantic torpedo (Tetronarce nobiliana) is a species of electric ray in the familyTorpedinidae. It is found in the Atlantic Ocean, from Nova Scotia to Brazil in the west and from Scotland to West Africa and off southern Africa in the east, occurring at depths of up to 800 m (2,600 ft), and in the Mediterranean Sea. Younger individuals generally inhabit shallower, sandy or muddy habitats, whereas adults are more pelagic in nature and frequent open water. Up to 1.8 m (6 ft) long and weighing 90 kg (200 lb), the Atlantic torpedo is the largest known electric ray. Like other members of its genus, it has an almost circular pectoral fin disk with a nearly straight leading margin, and a robust tail with a large triangular caudal fin. Distinctive characteristics include its uniform dark color, smooth-rimmed spiracles (paired respiratory openings behind the eyes), and two dorsal fins of unequal size.
Solitary and nocturnal, the Atlantic torpedo is capable of generating up to 220 volts of electricity to subdue its prey or defend itself against predators. Its diet consists mainly of bony fishes, though it also feeds on small sharks and crustaceans. It is an aplacental viviparous species, wherein the developing embryos are nourished by yolk and later maternally provided histotroph ("uterine milk"). Females give birth to up to 60 young following a gestation period of one year. The electric shock of this species can be quite severe and painful, though it is not fatal. Because of its electrogenic properties, the Atlantic torpedo was used in medicine by the Ancient Greeks and Romans and became the namesake of the naval weapon. Prior to the 19th century, its liver oil was used as lamp fuel, but it is no longer of any economic value. The International Union for Conservation of Nature (IUCN) has listed this species as Least Concern; it is caught unintentionally by commercial and recreational fishers, but the impact of these activities on its population is unknown. (Full article...)
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The Australian swellshark (Cephaloscyllium laticeps) or draughtboard shark, is a species of catshark, and part of the familyScyliorhinidae, endemic to southern Australia. This bottom-dwelling species can be found on the continental shelf down to a depth of 220 m (720 ft). Usually measuring 1 m (3 ft 3 in) long, it is a stout-bodied, broad-headed shark with a short tail and a first dorsal fin much larger than the second. It can be identified by its variegated dorsal coloration of brown or grey patches and numerous spots.
Australian swellsharks are sedentary and mainly nocturnal, with most individuals remaining within the same local area throughout the year. It feeds on small crustaceans, cephalopods, and fish. When threatened, it responds by rapidly taking in water or air to inflate its body, hence the name "swellshark". This shark is oviparous and females lay pairs of distinctively ridged egg capsules at 20- to 30-day intervals. The eggs hatch after 11–12 months. Harmless and of little commercial interest, many Australian swellsharks are caught incidentally in gillnets and bottom trawls but usually survive to be released because of their extreme hardiness. As a result, the International Union for Conservation of Nature (IUCN) has assessed this species as of Least Concern. (Full article...)
The case began in 2002 when a Coast Guard crew working from a Navy ship stopped and searched the King Diamond II, a U.S.-flagged, Hong Kong–based vessel in international waters off the coast of Guatemala. On board the ship they found shark fins, equivalent to 32.3 tons (29.3 tonnes) but without any corresponding shark carcasses. The Coast Guard, upon further investigation, found documentary evidence that the KD II had arranged to meet fishing vessels at predetermined locations and buy various quantities of fins. These activities were believed to violate the Shark Finning Prohibition Act of 2000 (SFPA). The fins were thus seized and the ship escorted to San Diego, the nearest American port. (Full article...)
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The deepwater stingray or giant stingaree (Plesiobatis daviesi) is a species of stingray and the sole member of the familyPlesiobatidae. It is widely distributed in the Indo-Pacific, typically over fine sediments on the upper continental slope at depths of 275–680 m (900–2,230 ft). This species reaches 2.7 m (8.9 ft) in length and 1.5 m (4.9 ft) in width. It has an oval pectoral fin disc with a long, flexible, broad-angled snout. Most of the entire latter half of its tail supports a distinctively long, slender, leaf-shaped caudal fin. Its coloration is dark above and white below, and its skin is almost completely covered by tiny dermal denticles.
The Galapagos shark (Carcharhinus galapagensis) is a species of requiem shark, in the family Carcharhinidae, found worldwide. It favors clear reef environments around oceanic islands, where it is often the most abundant shark species. A large species that often reaches 3.0 m (9.8 ft), the Galapagos reef shark has a typical fusiform "reef shark" shape and is very difficult to distinguish from the dusky shark (C. obscurus) and the grey reef shark (C. amblyrhynchos). An identifying character of this species is its tall first dorsal fin, which has a slightly rounded tip and originates over the rear tips of the pectoral fins.
The Galapagos shark is an active predator often encountered in large groups. It feeds mainly on bottom-dwelling bony fishes and cephalopods; larger individuals have a much more varied diet, consuming other sharks, marine iguanas, sea lions, and even garbage. As in other requiem sharks, reproduction is viviparous, with females bearing litters of 4–16 pups every 2 to 3 years. The juveniles tend to remain in shallow water to avoid predation by the adults. The International Union for Conservation of Nature (IUCN) has assessed this species as least concern, but it has a slow reproductive rate and there is heavy fishing pressure across its range. (Full article...)
Cretoxyrhina (/krɪˌtɒksiˈrhaɪnə/; meaning 'Cretaceous sharp-nose') is an extinct genus of large mackerel shark that lived about 107 to 73 million years ago during the late Albian to late Campanian of the Late Cretaceous. The type species, C. mantelli, is more commonly referred to as the Ginsu shark, first popularized in reference to the Ginsu knife, as its theoretical feeding mechanism is often compared with the "slicing and dicing" when one uses the knife. Cretoxyrhina is traditionally classified as the likely sole member of the familyCretoxyrhinidae but other taxonomic placements have been proposed, such as within the Alopiidae and Lamnidae.
Measuring up to 8 m (26 ft) in length and weighing over 4,944 kg (10,900 lb), Cretoxyrhina was one of the largest sharks of its time. Having a similar appearance and build to the modern great white shark, it was an apex predator in its ecosystem and preyed on a large variety of marine animals including mosasaurs, plesiosaurs, sharks and other large fish, pterosaurs, and occasionally dinosaurs. Its teeth, up to 8 cm (3.1 in) long, were razor-like and had thick enamel built for stabbing and slicing prey. Cretoxyrhina was also among the fastest-swimming sharks, with hydrodynamic calculations suggesting burst speeds of up to 70 km/h (43 mph). It has been speculated that Cretoxyrhina hunted by lunging at its prey at high speeds to inflict powerful blows, similar to the great white shark today, and relied on strong eyesight to do so. (Full article...)
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The jamming avoidance response is a behavior of some species of weakly electric fish. It occurs when two electric fish with wave discharges meet – if their discharge frequencies are very similar, each fish shifts its discharge frequency to increase the difference between the two. By doing this, both fish prevent jamming of their sense of electroreception.
The dusky shark (Carcharhinus obscurus) is a species of requiem shark, in the family Carcharhinidae, occurring in tropical and warm-temperate continental seas worldwide. A generalistapex predator, the dusky shark can be found from the coast to the outer continental shelf and adjacent pelagic waters, and has been recorded from a depth of 400 m (1,300 ft). Populations migrate seasonally towards the poles in the summer and towards the equator in the winter, traveling hundreds to thousands of kilometers. One of the largest members of its genus, the dusky shark reaches more than 4 m (13 ft) in length and 350 kg (770 lb) in weight. It has a slender, streamlined body and can be identified by its short round snout, long sickle-shaped pectoral fins, ridge between the first and second dorsal fins, and faintly marked fins.
Adult dusky sharks have a broad and varied diet, consisting mostly of bony fishes, sharks and rays, and cephalopods, but also occasionally crustaceans, sea stars, bryozoans, sea turtles, marine mammals, carrion, and garbage. This species is viviparous with a three-year reproductive cycle; females bear litters of 3–14 young after a gestation period of 22–24 months, after which there is a year of rest before they become pregnant again. This shark, tied with the Spiny dogfish as a result is the animal with the longest gestation period. Females are capable of storing sperm for long periods, as their encounters with suitable mates may be few and far between due to their nomadic lifestyle and low overall abundance. Dusky sharks are one of the slowest-growing and latest-maturing sharks, not reaching adulthood until around 20 years of age. (Full article...)
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The Jersey Shore shark attacks of 1916 were a series of shark attacks along the coast of New Jersey, in the United States, between July 1 and 12, 1916, in which four people were killed and one critically injured. The incidents occurred during a deadly summer heat wave and polio epidemic in the United States that drove thousands of people to the seaside resorts of the Jersey Shore. Since 1916, scholars have debated which shark species was responsible and the number of animals involved, with the great white shark and the bull shark most frequently cited.
Personal and national reaction to the fatalities involved a wave of panic that led to shark hunts aimed at eradicating the population of "man-eating" sharks and protecting the economies of New Jersey's seaside communities. Resort towns enclosed their public beaches with steel nets to protect swimmers. Scientific knowledge about sharks before 1916 was based on conjecture and speculation. The attacks forced ichthyologists to reassess common beliefs about the abilities of sharks and the nature of shark attacks. (Full article...)
The whale shark (Rhincodon typus) is a slow-moving, filter-feedingcarpet shark and the largest known extantfishspecies. The largest confirmed individual had a length of 18.8 m (61.7 ft). The whale shark holds many records for size in the animal kingdom, most notably being by far the most massive living non-cetacean animal. It is the sole member of the genus Rhincodon and the only extant member of the family Rhincodontidae, which belongs to the subclass Elasmobranchii in the class Chondrichthyes. Before 1984 it was classified as Rhiniodon into Rhinodontidae.
Whale sharks inhabit the open waters of all tropical oceans. They are rarely found in water below 21 °C (70 °F). Whale sharks' lifespans are estimated to be between 80 and 130 years, based on studies of their vertebral growth bands and the growth rates of free-swimming sharks. Whale sharks have very large mouths and are filter feeders, which is a feeding mode that occurs in only two other sharks, the megamouth shark and the basking shark. They feed almost exclusively on plankton and small fishes and pose no threat to humans. (Full article...)
The following are images from various fish-related articles on Wikipedia.
Image 1Shortfin mako shark make long seasonal migrations. They appear to follow temperature gradients, and have been recorded travelling more than 4,500 km in one year. (from Pelagic fish)
Image 15Coral reefs support flourishing ecosystems, paradoxically in clear, low nutrient waters, along tropical continental coasts and around volcanic islands. Coral reef fish are numerous and diverse. (from Coastal fish)
Image 16Humans seldom encounter frilled sharks alive, so they pose little danger (though scientists have accidentally cut themselves examining their teeth). (from Deep-sea fish)
Image 17The stoplight loosejaw is also one of the few fishes that produce red bioluminescence. As most of their prey cannot perceive red light, this allows it to hunt with an essentially invisible beam of light. (from Deep-sea fish)
Image 18The rattail Coryphaenoides armatus (abyssal grenadier) on the Davidson Seamount at a depth of 2,253 metres (7,392 ft). (from Deep-sea fish)
Image 19The huge ocean sunfish, a true resident of the ocean epipelagic zone, sometimes drifts with the current, eating jellyfish. (from Pelagic fish)
Image 21The humpback anglerfish is a bathypelagic ambush predator, which attracts prey with a bioluminescent lure. It can ingest prey larger than itself, which it swallows with an inrush of water when it opens its mouth. (from Pelagic fish)
Image 23The stoplight loosejaw has a lower jaw one-quarter as long as its body. The jaw has no floor and is attached only by a hinge and a modified tongue bone. Large fang-like teeth in the front are followed by many small barbed teeth. (from Deep-sea fish)
Image 25Red snapper, are generalized reef feeders with standard jaw and mouth structures that allow them to eat almost anything, though they prefer small fish and crustaceans. (from Coral reef fish)
Image 29Areas of upwelling in red (from Coastal fish)
Image 30Most of the rest of the mesopelagic fishes are ambush predators, such as this sabertooth fish. The sabertooth uses its telescopic, upward-pointing eyes to pick out prey silhouetted against the gloom above. Their recurved teeth prevent a captured fish from backing out. (from Pelagic fish)
Image 39The stargazer is an ambush predator which can deliver both venom and electric shocks. It has been called "the meanest thing in creation". (from Coastal fish)
Image 43Lanternfish are partial residents of the ocean epipelagic zone During the day they hide in deep waters, but at night they migrate up to surface waters to feed. (from Pelagic fish)
Image 44Herring reflectors are nearly vertical for camouflage from the side. (from Pelagic fish)
Image 50Young, red flabby whalefish make nightly vertical migrations into the lower mesopelagic zone to feed on copepods. When males mature into adults, they develop a massive liver and then their jaws fuse shut. They no longer eat, but continue to metabolise the energy stored in their liver. (from Pelagic fish)
Image 53Long-snouted lancetfish. Lancetfish are ambush predators which spend all their time in the mesopelagic zone. They are among the largest mesopelagic fishes (up to 2 m). (from Deep-sea fish)
Image 54In the foreground is an orange-lined triggerfish displaying spines. Triggerfish have mouths that crush shells. Orange-lined triggerfish are particularly aggressive. The black and white fish are three-stripe damselfish and the unstriped fish are blue-green chromis damselfish. If the triggerfish attacks, the damselfish will hide in the nearby cauliflower coral. If the triggerfish wants to hide, it will squeeze into a coral crevice and lock itself in place with its spines. (from Coral reef fish)
Image 55Oceanic fish inhabit the oceanic zone, which is the deep open water which lies beyond the continental shelves. (from Pelagic fish)
Image 62Profile illustrating the shelf, slope and rise (from Demersal fish)
Image 63Surgeonfish are among the most common of coral reef herbivores, often feeding in shoals. This may be a mechanism for overwhelming the highly aggressive defence responses of small territorial damselfishes that vigorously guard small patches of algae on coral reefs. (from Coral reef fish)
Image 71The usually placid yellow tang can erect spines in its tail and slash at its opponent with rapid sideways movements (from Coral reef fish)
Image 72Most mesopelagic fishes are small filter feeders that ascend at night to feed in the nutrient rich waters of the epipelagic zone. During the day, they return to the dark, cold, oxygen-deficient waters of the mesopelagic where they are relatively safe from predators. Lanternfish account for as much as 65% of all deep sea fish biomass and are largely responsible for the deep scattering layer of the world's oceans. (from Pelagic fish)
Image 73Pacific decadal anomalies – April 2008 (from Pelagic fish)
Image 74The giant whale shark, another resident of the ocean epipelagic zone, filter feeds on plankton, and periodically dives deep into the mesopelagic zone. (from Pelagic fish)
Image 75Some flatfish can camouflage themselves on the ocean floor (from Demersal fish)
Image 76Many bristlemouth species, such as the "spark anglemouth" above, are also bathypelagic ambush predators that can swallow prey larger than themselves. They are among the most abundant of all vertebrate families. (from Pelagic fish)
Image 78Scale diagram of the layers of the pelagic zone (from Pelagic fish)
Image 79Cod-like fishes, like this morid cod have a barbel (fleshy filament) on their lower jaw which they use to detect prey buried in the sand or mud. (from Coastal fish)
The Atlantic spadefish is a species of marine fish endemic to the shallow waters off the coast of the southeastern United States and in the Caribbean Sea. They are similar in appearance to fresh waterangelfish, but much larger, reaching up to three feet (0.9 m) in length. Due to their reputation as strong fighters, they are popular game fish, especially during the summer months when they are most active.
In American English, the name gar (or garpike) is strictly applied to members of the Lepisosteidae, a family including seven living species of fish in two genera that inhabit fresh, brackish, and occasionally marine, waters of eastern North America, Central America, and the Caribbean islands.
A discus (Symphysodon discus) is guarding its eggs. As for most cichlids, brood care is highly developed with both the parents caring for the young. Additionally, adult discus produce a secretion through their skin, off which the larvae live during their first few days.
An Atlantic salmon (Salmo salar) egg hatching. The Alevin (larva) has grown around the remains of the yolk sac - visible are the arteries spinning around the yolk and little oildrops, also the gut, the spine, the main caudalblood vessel, the bladder and the arcs of the gills. In about 24 hours it will be a fry without yolk sac.
Brachysomophis cirrocheilos, the stargazer snake eel, is a marine fish belonging to the family Ophichthidae. It is native to shallow tropical and subtropical waters in the western Indo-Pacific region. It hunts at night for crustaceans and small fish, after which it submerges itself into the sediment tail first and remains there all day, with just its eyes and the top of its head projecting, as seen here in Batangas Bay in the Philippines.
The mandarinfish (Synchiropus splendidus, not to be confused with the similarly named mandarin fish) is a small (~6 cm or 2.4 in), brightly-colored member of the dragonet family, popular in the saltwater aquarium trade. The mandarinfish is native to the Western Pacific, ranging approximately from the Ryukyu Islands south to Australia.
The flying gurnard is a fish of tropical to warm temperate waters on both sides of the Atlantic Ocean. When excited, it spreads its "wings", semi-transparent appendages tipped with a phosphorescent bright blue coloration which are used to frighten predators.
Rhinogobius flumineus, also known as the lizard goby, is a species of goby in the family Oxudercidaeendemic to Japan, seen here in Hamamatsu, Shizuoka Prefecture. A small freshwater fish found in fast-flowing streams, it maintains its position against the current by gripping a rock with a sucker formed from two of its fins. The fish's mouth is slightly asymmetric; dextral (right-sided) fish tend to curve their bodies to the right as they rest, while sinistral (left-sided) fish tend to adopt a left-curving posture. The fish are omnivorous, picking edible items off the stream bed with the side of the mouth, but dextral and sinistral fish show no preference for which side of the mouth they use for this purpose.
Mudskippers, such as this Periophthalmodon septemradiatus, are uniquely adapted to a completely amphibious lifestyle. They are active when out of water, feeding and interacting with one another, as well as defending their territories.
Icefish are a type of Antarctic fish belonging to various families, including the Channichthyidae family. They have no haemoglobin and their blood is transparent. They feed on krill, copepods, and other fish. Icefish rely on well-oxygenated water and absorb oxygen directly through the skin as they lack red blood cells.
The round ribbontail ray (Taeniura meyeni) is a species of stingray in the family Dasyatidae, found throughout the nearshore waters of the tropical Indo-Pacific region. Reaching 1.8 m (6 ft) across, this large ray is characterized by a thick, rounded pectoral fin disc covered by small tubercles on top, and a relatively short tail bearing a single venomous spine. The ray is well-camouflaged when lying on the seabed; it is largely nocturnal, and preys on molluscs, crustaceans and bony fish. Mature females bear litters of up to seven pups, which are fed during gestation on "uterine milk", a product secreted by the walls of the oviduct. This round ribbontail ray was photographed in Lakshadweep, India.
The Eurasian ruffe (Gymnocephalus cernua) is a species of freshwater fish found in temperate regions of Europe and Asia. The aggressive fish is known to reproduce rapidly, leading to problems when it is introduced to foreign bodies of water.
The Mini Edition of the Fish Portal is available for you to use on your wikipedia user page or talk page. It uses minimum space but retains many crucial features of the portal. To use it, place {{Portal:Fish/Mini portal}} on the designated page. See here for an example of the mini portal on a user page.
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