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Last updated date: 23rd May 2024
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Introduction to Flounder

Flounder fish, any of many flatfish species belonging to the Achiropsettidae, Pleuronectidae, Paralichthyidae, and Bothidae families (order Pleuronectiformes).

The flounder has an interesting Morphogenetic Ally. It is bilaterally symmetrical when it is born, with one eye on each side, and it swims near the sea's surface. However, after a few days, it begins to tilt to one side, and the eye on that side migrates to what will ultimately become the fish's top side. A variety of additional complicated changes in bones, nerves, and muscles occur as a result of this growth, and the flounder's underbelly loses its colour. The fish lives on the bottom as an adult, with the eyes side on top.

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The European flounder (Platichthys flesus), a European marine and freshwater food and sport fish that grows to a length of 50 cm (20 inches) and a weight of 2.7 kg (6 pounds); the starry flounder (Platichthys stellatus), a North Pacific species that averages about 9 kg (20 pounds); and the winter flounder (Pseudopleuronectidae) are among the approximately 100 species of the Pleuronectes.

Define Flounder

Flounder are saltwater flatfish that are captured using a bottom trawl or a static net. During the summer and autumn, they can be seen in large numbers in the North-East Atlantic. The fragrance of flounder is peppery or woody. They have a deep, musty, peppery flavour that comes from the darker flesh near the top of the fillet.

Flounder meat has a fairly soft texture, with initial moisture that gives it a crumbly feeling in the mouth. Skinned, filleted, and fried flounder is best paired with robust vegetables like kale. Flounder is quite similar to Plaice, thus it's a decent substitute for Dabs.

Flounder Fish

Flounder fish is a kind of flatfish. They are demersal fish that may be found at the bottom of seas all around the world, with certain species found their way into estuaries. Flatfish is a catch-all name for over 700 different fish species. Flounder, Halibut, Sole, Plaice, Dab, Turbot, and more species are included in the group. It's important to note that half of the time, these names aren't based on any scientific classification. Flounder is the scientific name for almost all of our favourite flatfish, although most of them go by another name. Flatfish live their whole lives on the seafloor, waiting for a meal to swim along. As a result, they're well suited to a life on the seafloor. If they ever leave their muddy habitat, their speckled skin changes colour to fit their environment, and their white underside renders them inconspicuous from below. 

To prove this point, their whole head is twisted sideways. Flounder are born spherical, but their bodies flatten out as they mature. Their lips twist to the side and one eye "migrates" across their skull. Depending on which eye moves, the group is classified into "right-eye" and "left-eye" fish. It's right-eyed if you hold it up with its eyes over its lips and it faces right. It's not pretty in any case.

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Flatfish are a common catch in both the United States and the United Kingdom.

Some similarities exist between the two countries, although many do not. This article will provide an overview of the most popular Flatfish in North America and the United Kingdom.

Types of Flatfish

1. Gulf Flounder - Paralichthys Albigutta

The Gulf flounder is a flatfish that swims on its side. When they swim, their two eyes are directed upward. They have sharp teeth on one side, two eyes on the other, and a white side. The species Paralichthys Albigutta is found in the western North Atlantic. Adults may be found in a range of environments, although they favour hard, sandy bottoms, while juveniles prefer high-salinity seagrass beds. Females achieve maturity between 1–2 years and live for 7–10 years. It is used both economically and recreationally. The northeastern coast of Florida is the centre of Paralichthys Albigutta abundance in the Gulf of Mexico. It is found in extremely small numbers west of the Mississippi River delta. They're a popular sport fish that may be caught with live bait, dead fish (like mullet), or even artificial or frozen baits like shrimp or clams.

Spearfishing and jigging are two popular methods for getting this flounder. This species has a recreational daily bag restriction of 10 and a minimum size of 12 inches. Gulf flounders appear to prefer the ocean floor, where they can mix in with their surroundings and strike their prey quietly.

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2. Southern Flounder - Paralichthys Lethostigma

The southern flounder, Paralichthys Lethostigma, is a large-toothed flounder native to the eastern and Gulf coasts of the United States. It is the largest and most economically valuable flounder in the western North Atlantic Ocean and Gulf of Mexico, making it a popular sport fish. It's a left-eyed flounder, which means the upside is coloured on the left side. Brown spots and blotches with scattered, ocellated spots and blotches cover the body.

This species normally grows a length of 12-14 inches. Southern flounder larvae and postlarval eat zooplankton. Small invertebrates make up the majority of the southern flounder's food as juveniles, but as they get larger, their diet turns to larger invertebrates and fish. Southern flounder are near top predators that eat on the bottom of the ocean and in the water column. Adult fish breed in coastal embayments and nearshore shelf waters during the warmer months, when the eggs develop until they are late-stage larvae, which are then carried into estuaries by currents, where they settle into the sediment and grow into juveniles. The juveniles remain in the estuaries until sexual maturity, at which point they leave to spawn.

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3. Summer Flounder  –  Paralichthys Dentatus

The large-tooth flounder family Paralichthyidae includes Paralichthys dentatus (Linnaeus, 1766), sometimes known as a fluke. On the body, there are usually 5 to 14 ocellated (eye-like) spots. They can change the colour and pattern of their dark side to fit the surrounding bottom, and they can burrow quickly into muddy or sandy bottoms, like other members of the left-eye flounder family. On both the upper and lower jaws, the teeth are sharp and well-formed. Summer flounders reach sexual maturity at two years old, weigh one to three pounds, and are normally 15 to 20 inches long, however, they can grow to be as large as 26 pounds and live up to 20 years, with females being the largest and oldest.

Female flounder have been observed to live to be 17 years old, while male flounder have been recorded to live to be 15 years old. [three] Sand lance, menhaden, Atlantic silverside, mummichog killifish, small bluefish, porgies, squid, shrimp, and crabs are among the ambush prey for adults, who often lie buried with only their minds exposed to ambush prey such as sand lance, menhaden, Atlantic silverside, mummichog killifish, small bluefish, porgies, squid, shrimp, and crabs.

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4. Halibut – Hippoglossus Stenolepis

Halibut is the common name for two flatfish species of the genus Hippoglossus from the right-eye flounder family, as well as, in some areas, and less often, other large flatfish species. Because of its popularity on Catholic holy days, the name is derived from haly (holy) and butte (flatfish). Halibut are a demersal fish that is popular as both a food fish and a sport fish.

Halibut are dark brown on top with an off-white underbelly and have very microscopic scales embedded in their skin that are invisible to the human eye. Halibut have one eye on each side of the head when they are born. Then, about six months later, one eye migrates to the other side of the skull during larval metamorphosis. Once the skull has entirely ossified, the eyes are permanently fixed. The stationary-eyed side darkens to match the top side at the same time, while the other side remains white. Countershading is a colour scheme that hides halibut from above (blending with the ocean floor) and below (blending with the light from the sky).

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5. Olive Flounder – Paralichthys Olivaceus

The olive flounder (Paralichthys olivaceus), sometimes known as bastard halibut or Japanese halibut, is a temperate marine large-tooth flounder endemic to the western Pacific Ocean.

When described in the context of those nations, it is commonly referred to as the Japanese flatfish or Korea(n) flatfish (). It is the world's most valuable finfish, and due to its quick growth rate and popularity in Korea, it is recognised to be ideal for aquaculture.  It is 103 cm (41 in) in length and weighs 9.1 kg (20 lb).  Its genome and transcriptome were sequenced in 2017 as a model for flatfish asymmetry research. The olive flounder may be found in soft, muddy offshore sea areas with water depths of up to 100 metres.

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6. Winter Flounder – Pseudopleuronectes Americanus

The black back, commonly known as the winter flounder (Pseudopleuronectes americanus), is a right-eyed ("dextral") flatfish of the Pleuronectidae family. It is found along the western north Atlantic coast, from Labrador, Canada, to Georgia, USA, though it is less prevalent south of Delaware Bay. It is the most common near-shore (shallow-water) flounder in the seas from Newfoundland to Massachusetts Bay, growing to a maximum length of 61 cm and a weight of 2.25 kg. On Georges Bank, the species grows bigger, reaching 70 cm in length and weighing 3.6 kg. Up to 3.3 million demersal, sticky eggs are laid by winter flounder, which are kept in their spawning grounds. Larvae of around 3 mm in length hatch in two to three weeks, depending on temperature.

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7. Witch Flounder – Glyptocephalus Cynoglossus

Glyptocephalus Cynoglossus, also known as the witch, witch flounder, pole flounder, Craig fluke, Torbay sole, and grey sole in English, is a flatfish species belonging to the Pleuronectidae family.

It may be found on muddy seabeds in deep water on both sides of the North Atlantic Ocean. As a food fish, it is important in northern European fisheries. The right-eyed flatfish Glyptocephalus Cynoglossus has a small mouth that reaches the forward edge of the lower eye. A single set of tiny, incisor-like teeth can be found in the mouth. On its blind side, it has a small head that takes up a fifth of its total length and huge, open blister-like mucous pits. Its body is oval and strongly compressed dorsally. The body is elongated, with a usual length 2.5-3.5 times greater than the breadth. With 110-140 scales, the lateral line is pretty straight and runs the length of its body.

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8. European Flounder – Platichthys Flesus

The European flounder (Platichthys flesus) is a flatfish that lives in European coastal waters from the White Sea to the Mediterranean and the Black Sea. It was accidentally introduced into the United States and Canada via ballast water shipping. It is captured and consumed by humans. European flounders have an oval form and are generally right-handed. It usually grows to be approximately 30 cm long, while it has been known to grow to be as long as 60 cm. The upper surface of this fish is normally a drab brown or olive colour with reddish patches and brown blotches, and it may change colour to fit in with its environment.

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Eye Migration

Larval flounder have one eye on each side of their head when they are born, but one eye migrates to the opposite side of the body when they grow from larval to the juvenile stage during metamorphosis.

As a result, both eyes are now on the up-facing side. The species type determines which side the eyes move to. A flounder alters its habits as an adult and camouflages itself by laying on the ocean floor to protect itself from predators.

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flounder ambush their prey by feeding around bridge piles, docks, and coral reefs in soft muddy sections of the seabed. Fish spawn, crustaceans, polychaetes, and tiny fish make up the majority of a flounder's diet. Flounder may reach lengths of 22–60 centimetres (8.7–23.6 in) with a maximum size of 95 cm (37 in). Their breadth is roughly equal to half of their length. Male Platichthys have been discovered up to 130 kilometres (80 miles) off the coast of northern Sardinia, occasionally with thick barnacle encrustations. Mariculture Technologies in Greenport, New York, is breeding fluke, a form of flounder, in open water.


The flounder is bilaterally symmetrical, with an eye on each side, and swims near the surface of the sea. After a few days, however, it begins to lean to one side and the eye on that side begins to migrate to what eventually becomes the top side of the fish. As an adult, the fish lives on the bottom, with the eyed side uppermost. A flounder alters its habits as an adult and camouflages itself by laying on the ocean floor to protect itself from predators. Flounder may reach lengths of 22–60 centimetres (8.7–23.6 in) with a maximum size of 95 cm (37 in) Their breadth is roughly equal to half of their length. Mariculture Technologies in Greenport, New York.

FAQs on Flounder

Q.1) Is Flounder Fish Good to Eat?

Answer: Nutritional Values and Health Advantages

Pacific Flounder, which can be found at the bottom of oceans and seas, is a fantastic fish to have for supper since it has a great flavour and is healthful.

Q.2) What is the Most Dangerous Fish to Eat?

Answer: Puffer Fish (or Fugu) 

  1. Red LionFish.

  2. Chilean Sea Bass. 

  3. Any Fish in Sushi.

  4. Octopus (not a fish, but close enough)

  5. Shark. 

  6. Swordfish.

Q.3) What is Flounder Meaning in the Dictionary?

Answer: Flounder meaning is to struggle with stumbling or plunging movements.

Q.4) What is the Most Unhealthy Fish to Eat?

Answer: 6 Fish to Avoid

  • Bluefin Tuna.

  • Chilean Sea Bass (aka Patagonian Toothfish)

  • Grouper.

  • Monkfish.

  • Orange Roughy.

  • Salmon (farmed)