Get unlimited access to our EXCLUSIVE Content and our archive of subscriber stories. The most obvious characteristic of the flatfish is its asymmetry, with both eyes lying on the same side of the head in the adult fish. The flounders with left-handed stipulations make up approximately a third of the population. Munroe, Thomas A (2005) "Distributions and biogeography." Their diet is composed mostly of crustaceans and fishes. Because mackerel has strong fish flavor, it is best served with acidic sauces. Lets look in more detail at all the various types of popular fish you can find in restaurants, supermarkets, and fish markets. The firm flexible rod found in the dorsal area in chordates is called the. Others tip over to play possum, only to leap up and snatch unsuspecting prey. The majority of tonguefish are smaller than 30 cm (12 inches). Carnivores eat a diet of eating tiny fish and crustaceans and bottom invertebrates, particularly annulids. They are found at 50 percent of depth, which is approximately 100 meters. Compared to salmon, trout has a similar taste but a more delicate flakier flesh. If you were to imagine what kind of fish Picasso would paint, it would be the flatfish., Photo credits: Today a large number of fish from various groups are flatfish. In many species, both eyes lie on one side of the head, one or the other migrating through or around the head during development. An observation of a flatfish from the Bathyscaphe Trieste at the bottom of the Mariana Trench at a depth of almost 11km (36,000ft) has been questioned by fish experts, and recent authorities do not recognize it as valid. Who created it? You will also find out about which kinds of fish to choose if you want a mild-flavored fish or strong-flavored one. How did this mountain lion reach an uninhabited island? Sometimes plaice are called flounder because the name flounder refers to fish in the suborder Pleuroncetoidei, Bothidae, and Paralichthyidae. As per FAO (Food and Agriculture Organization which is an agency of the United Nations), total landings across these regions are around 15,000 tonnes per year, and the UK is part of the total at 3000 tonnes. In the late 2000s, Friedman reexamined 45-million-year-old fish fossils that other researchers had dredged up from Monte Bolca, an ancient petrified coral reef in Italy. Plaice is like flounder, plaice is found only in the waters surrounding Finland. Garrett, D.L. It is now a young adult bottomfeeder with two eyes on the same side of its head, a contorted mouth, and one fin squashed against the sand. The jet propels them forward. Ad-free experience & advanced Chrome extension. However, it is much bigger. Turbot is an expensive flatfish with a strong taste. Updated on 04/08/17. Save my name, email, and website in this browser for the next time I comment. What are the advantages and disadvantages of video capture hardware? Instead of drifting down, it falls up, and rather than flakes of ice, its made of innumerable diaphanous eggs that rise from the bottom of the ocean to the surface. Flatfish larvae require light to swim upright, so when the lights go off, they swim erratically. Our free guide can help keep your tank clean and your fish healthy. However, what the fish lacks in looks, it makes up for in taste. In the absence of visible light, the baby flatfish were incapable of staying upright. . [5] The largest families are Soleidae, Bothidae and Cynoglossidae with more than 150 species each. This week in Fish: Flatworm mimic and shark teeth. They're bottom-dwelling species, which range from Baja up to the Bering Sea. rhymes. The larva also loses its swim bladder and spines, and sinks to the bottom, laying its blind side on the underlying surface. This type of fish also popular for people who enjoy the Mediterranean cuisine. But since the time of Charles Darwin, a handful of biologists have become fascinated with the flatfish for an entirely different reason: its unique evolutionary history. If everyone is studying fruit flies and zebrafish, Ill be damned if I am going to study them. Tuna is a popular type of edible fish in many restaurants. How a zoo break-in changed the life of an owl called Flaco, Naked mole rats are fertile until they die, study finds. Certain species can reach a certain size and have enough to make them important to fishing. 3. It comes with an apricot-colored skin that is delicious when served crispSanddab sandwiches are a favorite local food! Darwin worried that the relative scarcity of such transitional fossils would doom his theory. Red mullet (Mullus barbatus) is a species of goatfish that is popular in Mediterranean cuisine. Dark and oily fish is usually strong-flavored fish and some delicious kinds are mackerel, sardines, tuna, and salmon. Their color blends beautifully with the bottom, and they are able to swiftly alter their color to blend with the substratum. You think pimples and prom were awkward? Similar to salmon, trout start their lives in lakes and rivers before heading out to sea. On the Validity of the Trieste Flatfish: Dispelling the Myth. Ling is a firm-fleshed and versatile fish that can be cooked in many ways. It seems that habitat was a vacuum, and nature abhors a vacuum, so flatfish adapted to it.. The prevailing story has been that modern flatfish evolved from bilateral fish, whichlike goldfish and most familiar specieshave right and left sides that mirror one another. The spots can be rusty red (can be confused when confused with plaice). It has a light and delicate taste; however, it has an overall texture that is more firm than cod or tilapia. Many fish lovers rate sea bream as one of the tastiest of all the whitefish available. habit of mind. Rainbow trout (Oncorhynchus mykiss) has light pink flesh and a mildly fishy flavor that is very delicate. In Finland, there is a Finnish name for brill is, Silokampela, and the name in Portugal, the Portuguese name is Rodovalho. What is A person who sells flower is called? This is their main adaptation to living on the seabed (benthos). Explore a billion-year-old volcanic mystery on Lake Superior, A journey of the senses through Abu Dhabi, These Lake Superior islands are no place for amateurs. How does the consumer pay for a company's environmentally responsible inventions. A teacher walks into the Classroom and says If only Yesterday was Tomorrow Today would have been a Saturday Which Day did the Teacher make this Statement? All rights reserved. Social vs. medical egg freezing: Whats the difference? Red, pink, or orange fish are some of the tastiest fish and can be some of the most expensive. Cod is a mild-tasting fish with flaky white flesh. Flatfish quality is variable, and the most desirable ones possess uniform color and do not have to bleed, as stated by certain customers. They can also bury themselves quickly in the sand, protruding their independently moving eyes to keep watch without being seen. , Mivart wielded the flatfish like a weapon to bludgeon Darwins ideas. For example, the Achiridae were classified as a subfamily of Soleidae in the past, and the Samaridae were considered a subfamily of the Pleuronectidae. Trout is a species of freshwater fish in the same family as salmon and is found in lakes and rivers. A recent examination of two fossil species from the Eocene shows "the assembly of the flatfish bodyplan occurred in a gradual, stepwise fashion". Although this is classed as a white fish, it sometimes has pale pink flesh. More than 130 years later, paleobiologist Matt Friedman, now at Oxford University, identified exactly the type of fossils Darwin had in mind. Achiridae (American soles) Tonguefish are flat and drop-shaped fish that have small eyes, located on the right side with long dorsal as well as anal fins that connect with that of the tail fin. The pelvic fins bases extend. Its often described as a substitute for the sole, and since it is often presented in fillets, it can be difficult for the customer to distinguish it. Sometimes, the flesh can have a beige/gray tinge to it. Megrim is abundant in the UK as well as in southern Norway, Iceland, France, and Spain and a little less within the Mediterranean. It has a light brown skin that is topped by massive, rough scales and a few spots and a somewhat transparent aspect. Some cheap types of fish include mackerel, sardines, and tilapia. Please be respectful of copyright. Soon enough, though, these young flatfish lose all semblance of normalcy during one of the most difficult puberties of any animal on the planet. Sanddabs are typically caught commercially by bottom trawlers and occasionally smaller boats using hooks and lines. ratfish. But recently, scientists using clever experiments and advanced imaging have shown just how their curious anatomies came about. [22], The flounders and spiny turbots eat smaller fish, and have well-developed teeth. ; Pietsch, T.W. That shows the intermediate stages were at no particular disadvantage. Are They baby fish. Add Fish to Favorites Copy Definition Thesaurus. Wiley. In contrast to turbots, these fish are cheaper since they are commercially caught. From their new perch, the flatfishs constantly swiveling eyes provide 360 degree vision. Preopercular margins are not present. Fok THE MACE OF LACE WITH PLAICE IN A PLACE THAT BASES THE CASE. Apart from being an excellent source of healthy omega-3s, salmon is popular due to its non-fishy taste. When does spring start? Also, you can occasionally see other fish beings that are sold as Turbot in less well-known restaurants. They sometimes seek prey in the midwater, away from the bottom, and show fewer extreme adaptations than other families. [6][18][19] Juveniles of Soleichthys maculosus mimic toxic flatworms of the genus Pseudobiceros in both colours and swimming mode. [24] The researchers concluded, "the change happened gradually, in a way consistent with evolution via natural selectionnot suddenly, as researchers once had little choice but to believe."[23]. Its lean flesh makes for a unique flavor that differs from species to species. But evolution did not engineer them that way on purpose. For example, a dwarf gourami's official scientific name is Trichogaster laium,where the first word represents the animal genus and the second is the precise species within that genus. They are found in sites together with flatfish with the full cranial asymmetry. Rather, it changes from a cute, symmetrical little fish into a total anatomical disasterlike some unrecognizable object evolution made from clay in preschool and gleefully brought home to its parents, who kept it for sentimental value., Flatfish are the most asymmetrically-shaped vertebrate to ever live on earth.. This deliciously-tasting flatfish has a sweet flavor that some rate as better than turbot. (Related: Meet the millipede with the most legs on Earth.). Petrale Sole is an oval-shaped or round flounder with a mouth that is large and two eyes on the right side. Skin is, in fact, soft. From Simple English Wikipedia, the free encyclopedia. All fish are vertebrates, and types of fish are divided into groups such as bony fish, cartilaginous fish, and jawless fish. https://simple.wikipedia.org/w/index.php?title=Flatfish&oldid=8476595, Creative Commons Attribution/Share-Alike License. Every summer theres a snowfall in the sea. This answers first letter of which starts with M and can be found at the end of A. Syllables. sentences. Its small, typically less than 25cm (10 inches) long, and is light brown with dark spots. Do clownfish have a skeleton or exoskeleton. In the past decade, biologists have hit upon some of the answers. That of flounder usually ranges between 35 to 46. Plaice is a common name for 4 species of flatfish in the family Pleuronectidae. Most modern scientists who study this diverse familywhich includes halibut, soles and floundersare interested in farming the fish more efficiently. They can also be found in all waters of the United Kingdom. Plaice usually grows to a length of 20 (50 cm) and tastes great when baked, fried, grilled, or steamed. Instead of drifting down, it falls up, and rather than flakes of ice, it . Flatfish are exactly what they sound like: fish with thin, oval or diamond-shaped bodies that are lie flat on the seafloor. Bones and cartilage in the skull twist and shift, and one eye migrates across the head to . Salmon is a pink deep sea fish favored by many people. For the initial two years, they remain close to the shore. At the same period in our lives when the slightest blemish seems like a calamity, the flatfish is preparing to lose half of its face. What is the most delicious Flatfish you can eat? Click on any word to find out the definition, synonyms, antonyms, and homophones. Some swordfish caught at sea may have a pink tinge to their flesh due to feeding on shrimp. Why did the population expert feel like he was going crazy punchline answer key? There are several different kinds of flatfish. Squint of the fossil flatfish. The top of the brill is devoid of tubercules and is smooth too. Halibut is thicker, longer, and heavier than other Flatfish. Evolutionary biologists have long struggled to explain the flatfishs curious, asymmetrical anatomy. Instead, it works with what it has. Most people use common names when talking about aquarium fish. You have entered an incorrect email address! The young uns need to swim upright to catch plankton near the surface of the ocean. and 22 lb. Smaller species like the two-foot-long Greenland turbot will eat crabs, squid, and fish, while larger species, like the six-foot-long Atlantic halibut, will chase after cod, haddock, or even lobsters. Janvier, Philip 2008. Depending on their stage of metamorphosis, they either bobbed in the water with noses pointed down, as though weighted by lead, or they leaned over and drifted to the bottom of the tank like a falling leaf, landing on the same side every timethe one that would eventually become blind. Salmon is a healthy oily fish that is well-known for its pink-colored meaty flesh. The idea that flatfishes and millipedes have stumbled upon the same method of moving is intriguing, Flammang says. It comprises groups such as Bigeye Flounders, Southern Flounders, and Turbots. [6], Hybrids are well known in flatfishes. Please. Schreiber is getting close to solving the latter puzzle. All flatfish are rather flat, and are ray-finned fish. This is also one of the least fishy fish, so people who generally dont like fish may eat swordfish. Also, darker colored fish such as pink salmon or red tuna are very popular due to their rich taste and omega-3 fatty acids. The surface of the fish facing away from the sea floor is pigmented, often serving to camouflage the fish, but sometimes with striking coloured patterns. During their evolution, their eyes have moved so that they are on the same side, which the fish keeps uppermost. However the IUCN lists the Atlantic halibut, a fish popular for seafood and recreational angling, as endangered due to overfishing. Words that rhyme with case include base, face, place, chase, grace, space, ace, brace, lace and race. To find out, she filmed members of six flatfish species collected from Puget Sound as they maneuvered around the floor of a tank at the University of Washingtons Friday Harbor Laboratories. For example, wild salmon is usually a dark pink to red or orange color whereas farmed salmon is usually light pink. The 'extreme cruelty' around the global trade in frog legs, What does cancer smell like? Sea bass includes several fish species with white firm flesh and a delicate flavor. New AI may pass the famed Turing test. And that is what biologists love about the fishtheir functional freakiness. (25 kg). No misnomers here. I wanted to show that larval flatfish before metamorphosis were like goldfish, but lo and beholdHoly cow!they are different from the get go. Some species of tuna are also some of the largest edible fish in the sea. Namely, why did these animals abandon their previously symmetrical situation in life? Brill is found on sandy or mixed substrates as well as in waters that are less than fifty meters. Some flatfishes are also able to change their pigmentation to match the background, in a manner similar to some cephalopods. On a flatfishs sideways body, however, the fins that function as limbs in other walking species are no longer in the right position to support ground mobility. The turbot is a large, left-eyed flatfish found in sandy shallow coastal waters around Europe. These are generally white kinds of fish with a delicate taste and mild flavor. The plaice has between 4 and 7 bony bumps in the area behind the eye. Flatfish are exemplars of evolution at work. Its large head means that much of the fish is discarded when filleting. Were they to remain at the seafloor where they hatched, they would surely be vacuumed up by a roving sideways pair of lipsperhaps even by their own parents. White, flaky, mild fish are the most commonly consumed fish as they tend to be less expensive than pink or red fish. Which travel companies promote harmful wildlife activities? New AI may pass the famed Turing test. White, lean, and firm fish such as black sea bass, sword fish and pearlfish. Evolution is capable of producing a wonderfully streamlined, symmetrical bottom-feeding fish: we know them as skates and rays. What is wind chill, and how does it affect your body? Get expert advice to help your pet live its best life, 22 Small Fish for Your Freshwater Aquarium, List of Aquarium Fish Species by Common Name, Nitrate Poisoning in Freshwater Aquarium Fish, Common and Scientific Aquarium Fish Names Beginning with C, Common Fish Names Beginning With the Letter T. Mackerel is also a cheaper alternative to other dark fish such as tuna or kingfish. Get it free when you sign up for the Spruce Pets! This large species of fish in the family Salmonidae and is related to trout. Pleuronectidae (righteye flounders) Or did one eye begin migrating to accommodate a new lifestyle at the bottom of the sea? Some popular species of sea bass include European sea bass (Dicentrarchus labrax), Japanese sea bass (Lateolabrax japonicus), and Asian sea bass (Lates calcarifer). Brill is a variety of names that are based on various locations or even countries. John Dory is a type of white fish with medium flakes with somewhat firm texture, If there was a list for unsightly edible fish, then John Dory (Zeus faber) would probably win it. Flatfishes are total freaks of nature. (Related: How do flatfish see the ocean floor?). Sea bream is a popular fish dish in restaurants in Mediterranean countries. They're known as a "left-eyed" flounders with eyes on both their left sides of the head of the Sanddab. You can browse the rhymes for Case below. Some of them are fished commercially, like flounder, sole, turbot, plaice, and halibut. So ancient flatfish with eyes even a little closer together would have had a better chance of avoiding their predators bellies while still filling their own. Its whole body begins to tip over, so it has to swim at an angle. The Atlantic bluefin tuna can grow up to 15 ft. (4.6 m) long and weigh over 1,508 lb. Suborder Psettodoidei Copyright 1996-2015 National Geographic SocietyCopyright 2015-2023 National Geographic Partners, LLC. Its inactivity is higher in the daytime because it has primarily nocturnal habits. The flesh of the Pacific Sanddab is mild, sweet as well as low-fat. Their young are perfectly symmetrical, but the head is remodelled during a metamorphosis. Most people describe the taste of salmon as more meaty than fishy. Halibut is the biggest Flatfish found in the ocean that can reach 9 feet long and weighting upwards of 600 pounds! Flatfish range in color from a speckled brown, black, and beige, like a black sea turbot ; or spotted, like . In reality, 15,000 tonnes overstates the reality since megrim is an extremely inexpensive fish, and many fishing vessels have had the habit of historically (and most likely will are continuing to do so) to throw it away due to the fact that the price it fetches isnt worth the hassle of dealing with it. Can we bring a species back from the brink? Smoked cod has a delicate flavor and can be incorporated in many recipes like soups, fishcakes, and pies. ; and Hauser, L. (2007). Methods of cooking include grilling, pan-frying, baking and deep-frying. Theyre great when pan-fried, broiled, or baked and served with a simple salad or vegetable dish. Mackerel is a type of oily fish with a strong taste and is relatively cheap. But this raised the problem that one eye was always looking down into the sand and was effectively useless. Halibut that are large are usually referred to as barn doors, whereas smaller halibut are known as chickens. So, Fox wondered how these unconventional creatures managed to get around on the seafloor. It is found in bottoms that are covered by dirt or sand and expose its eyes only. Because of its meat-like texture, swordfish is a good fish to cook on the grill or put on skewers. The evolutionary origin of flatfish asymmetry. What is the name of a flatfish that rhymes with case? 9 things to know about Holi, Indias most colorful festival, Anyone can discover a fossil on this beach. In this article, you will learn about the most popular types of fish that we consume. Just as metamorphosis has proved an enormously successful strategy for insectsseparating larvae and adults so they do not compete for resources (think: nectar-slurping butterflies vs. leaf-munching caterpillars)flatfish larvae have clung to the vestiges of symmetry in order to distance themselves from their parents. What are the disadvantages of shielding a thermometer? While some common names refer to a single species, others may be used for an entire group of species, such as a genus or family, and still others have been used confusingly for multiple unrelated species or groups; the articles listed here should attempt to list the possible meanings if the common name is ambiguous. Most people use common names when talking about aquarium fish. The embryos and young specimens show bilateral symmetryhowever, the proportions of its body shift in the course of growth. This fish species is often identified by a light red stripe along the sides of its spotted body. Rhyme. batfish. definitions. The flank which has the eyes is different in accordance with the background. [1], Flatfishes lay eggs that hatch into larvae resembling typical, symmetrical, fish. With their lopsided eyes and tilted bodies, flatfishes like this starry flounder are the most asymmetrical creatures in the world. Then figure out what the total cost of the trip would be.? Can we bring a species back from the brink? , This is a good fish to use in recipes as its delicate flavor doesnt overpower food and it readily takes on other flavors. John Dory is often one of the more expensive fish on a restaurant menu. Turbot is an expensive flatfish with a strong taste Turbot ( Scophthalmus maximus) is one of the largest and most expensive edible flatfish. It has dense white flesh with a meaty texture and a mild taste. Flatfish are a group of fish that are found in oceans and seas throughout the world. Every summer there's a snowfall in the sea. Similarly, flatfish larvae that are deliberately blinded adopt a sideways swimming posture. Can You Eat Dead Fish Survivor? Brown trout (Salmo trutta) is a subgroup of the family Salmonidae that live in both freshwater and saltwater. cross the mind. Bats and agaves make tequila possibleand theyre both at risk, The new year once started in Marchhere's why, Jimmy Carter on the greatest challenges of the 21st century, This ancient Greek warship ruled the Mediterranean, 3 ways Jimmy Carter changed the world for the better, The meaning of the cross of ashes on Ash Wednesday, This disease often goes under-diagnosedunless youre white, The groundbreaking promise of cellular housekeeping. Gurnard has a firm white flesh that doesnt break apart easily when cooking. One of the reasons why this mild whitefish is popular is that it is a cheaper alternative to cod. Generally, brown trout has a stronger fish taste than rainbow trout and it also has light-colored flesh. Like many flatfish species, plaice has good flavor and is as tasty as some more expensive fish. All types of edible fish are high in nutrients and protein and can be the highlight of a tasty meal. Sole is considered to be the best Flatfish, both for its culinary qualities. 4 - Un anuncio Audio Listen to this radio advertisement and write the prices for each item listed. Heres why each season begins twice. Talk about cognitive dissonance. 2 syllables. (25 kg). However, most species of this flatfish weigh between 17 oz. When an organisms circumstances change and demand a completely different body, evolution cannot go back to the drawing board. In the dark, goldfish and other bilateral fish have no trouble staying in an upright position because they can rely on their inner ears, even when their eyes cannot see much of anything. Social vs. medical egg freezing: Whats the difference? As tuna cooks, it turns from red to a light tan color. The larvae typically have protective spines on the head, over the gills, and in the pelvic and pectoral fins. [20][21] Conversely, a few octopus species have been reported to mimic flatfishes in colours, shape and swimming mode. Different life stages inhabit very different regions of the ocean ecosystem. What if we could clean them out? A flatfish is a member of the ray-finned demersal fish order Pleuronectiformes, also called the Heterosomata, sometimes classified as a suborder of Perciformes. But it is best to look upon it as a group of fish which are adapted to the same habitat. They swim like this, and can hide in the sand waiting for prey on the ocean floor. Flatfish, one of the most asymmetrical organisms on Earth, use their fins to move around the seafloorsimilar to how millipedes walk. Sea bass is the name for a number of fish species in the families Serranidae, Moronidae, or Latidae. Cod (Gadus morhua) is one of the most popular types of whitefish, and Atlantic cod and Pacific cod the two most common species. What rhymes with flat-fish? When threatened, some modern fish are known to lie flat on their side on the seafloor and briefly bury themselves in the sand. Flatfish is considered a Whitefish[26] because of the high concentration of oils within its liver. Unfortunately, common names can refer to more than one fish. (500 g 10 kg). The taste, however, may depend on its species. Amphistium is a 50-million-year-old fossil fish which has been identified as an early relative of the flatfish, and as a transitional fossil. thesaurus. [1], In general, flatfishes rely on their camouflage for avoiding predators, but some have aposematic traits such as conspicuous eyespots (e.g., Microchirus ocellatus) and several small tropical species (at least Aseraggodes, Pardachirus and Zebrias) are poisonous. All rights reserved, thanks to their ability to mimic the various colors of the ocean floor. Suborder Soleoidei All rights reserved. Australian lungfish Australian prowfish (family Pataecidae) Ayu ( Plecoglossus altivelis) B Baikal oilfish Bala shark Ballan wrasse Bamboo shark Banded killifish Bandfish Banjo Bangus Banjo catfish Barb Barbel Barbeled dragonfish Barbeled houndshark Barbel-less catfish Barfish Barracuda Barracudina Barramundi Barred danio Barreleye Basking shark It has a deep flavor that will stand up well to strong ingredients such as garlic, herbs, and chili. 9 things to know about Holi, Indias most colorful festival, Anyone can discover a fossil on this beach. Once its landed in the water, its usually between 500g and 1500g and around 35cms in length. Campbell, Matthew A; Chanet, Bruno; Chen, JhenNien; Lee, MaoYing; Chen, WeiJen 2019. Petrale sole is a great source of protein that is low in fat along with calcium and other essential nutrients. Tilapia is a fish native to the Nile river from the family Oreochromis and is now a popular farmed fish all over the world. Most types of mackerel are identified by their grayish oily flesh and rich flavor. When searching for information, it is preferable to use the scientific name, which is normally in Latin. Like tuna and mackerel, swordfish is classed as an oily fish. guru hargobind. This page was last edited on 29 November 2022, at 02:05. Plaice is red with spots on its dark topside; however, it isnt an exact method of identification because flounders typically have similar spots. Lookup it up at Rhymes.com - the most comprehensive rhyming words dictionary on the web! An analysis of cladistics shows that this is a monophyletic family of Nine types of flatfish are included, and the most massive can reach 1 m in length. suggest new. Please be respectful of copyright. When does spring start? These meaty fish types are also important type of food because of their omega 3 fatty acids. This is one of the more unusual-looking fish you will see at the fish counter due to its scaly red and pink skin. [8], The taxonomy of some groups is in need of a review, as the last monograph covering the entire order was John Roxborough Norman's Monograph of the Flatfishes published in 1934. In some parts of the British Isles, smoked haddock is a popular dish. [7][2][3] The Paralichthyidae has long been indicated to be paraphyletic, with the formal description of Cyclopsettidae in 2019 resulting in the split of this family as well. Yet several fundamental conundrums remained. Plaice is a flat fish that rhymes with case. They feed on benthic invertebrates as well as tiny fish. Tuna is a deep-sea fish with meat ranging in color from pink to dark red. A flatfish is a member of the ray-finned demersal fish order Pleuronectiformes, also called the Heterosomata, sometimes classified as a suborder of Perciformes.In many species, both eyes lie on one side of the head, one or the other migrating through or around the head during development.