cosmoid scales in fishes

The external layer of scale... 2. The principal purpose of scales is to give fish external protection, but not all fish species have them. Furthermore, Early Triassic marine fishes had heavy ganoid or cosmoid scales that were not prone to rapid decay, and when coupled with the interlocking arrangement of the scales, provided a resistant barrier to environmental conditions and scavengers (Schäfer, 1972, Weigelt, 1989, Neuman, 1996). Cosmoid scales No such live fish can be found. In fish: The skin. Fish External Anatomy Placoid Scales Bony Scales • Cosmoid scales • Ganoid scales Bony Scales • Most teleosts, secondary loss in some eels, catfish, other taxa. These are found in lungfish and some fossil fishes. The scales were available in the body of certain Ostracoderms, placoderms, and wiped out sarcopterygian. Spines is made of enamel like basal plate of dentine like bony material. Ganoid. They have backwardly directed spines arising from a rounded basal plate embedded in dermis. Ganoid scales on the other hand are scales that are found in most fishes. Placoid. Cosmoid. This type of scales is found in Lungfishes and some fossil fishes. Elasmoid scales consist of a layer of isopedine lamellar bone with a layer of tubercles (typically made of bone) lying on top. Elasmoid scales consist of a layer of isopedine lamellar bone with a layer of tubercles (typically made of bone) lying on top. The scale terms are still in use even though Peters (1841) and many other subsequently have shown that there is no distinction between cycloid and ctenoid scales, except for serration or ctenae on the free field of ctenoid scales; both scale types may occur on the same fish (e.g., Percichthys; Arratia, 1982). The last two are called as bony ridge scales. Placoid Scales The paired fins act as active swimming organs and are also used for movement at the bottom of the sea. Scales were first developed in fish hundreds of millions of years ago, and since then they have undergone much evolution. Cosmoid scales have a hard, enamel-like outer layer, an inner layer of cosmine (a form of dentine), and then a layer of vascular bone (isopedine). Cosmoid scales are found in the Lungfishes (family Ceratodidae) and some fossil fishes. Scales of an Australian Lungfish from the fish collection. Cosmoid scales are similar to placoid scales and probably evolved from the fusion of placoid scales. Between the inner layer and outer layer is a vascular bone maintained by blood vessels. The cosmoid scale is covered on top by a hard enamel-like dentin, which imparts its characteristic sheen. Scales of an Australian Lungfish from the fish collection. Cosmoid scales are similar to placoid scales and probably evolved from the fusion of placoid scales. They consist of two basal layers of bone, a layer of dentine-like cosmine, and an outer layer of vitrodentine. COSMOID (most primitive) First found on ostracaderm agnathans, thick & boney - composed of: Ganoine (enamel outer layer) Cosmine (thick under layer) Spongy bone Lamellar bone Perhaps selected for protection against eurypterids, but decreased flexibility 2. 3) drink very little (if any) water. You can thank prehistoric fish for the enamel on your teeth. 2. However, bony fish have a single gill opening on each side. They have a basal layer of bone, a middle layer of dentine, and ganoine on the outside layer. The last two are called as bony ridge scales. Placoid (sharks and rays) 2. They are similar to cosmoid scales but have a much thicker layer of ganoine and grow by the addition of material all round. Placoid scales are found on cartilaginous fish and sharks. They consist of two basal layers of bone, a layer of dentine-like cosmine, and an outer layer of vitrodentine. 1. Some fishes like sole have ctenoid scales on the 'eyed' side of their body and cycloid scales on the other side. The primary categories of fish scales are placoid, cosmoid, ganoid, cycloid and ctenoid scales. That is why called Cosmoid scales. "Share your Knowledge, It’s a way to achieve Immortality" Home Science; Computer Science (C.S.) Fish Skeletal System – General Features And Its Composition. Regular scales Protection There are four main kinds of scales and numerous variations of each kind. Ganoid scales are similar to placoid scales but are covered with a peculiar enamel-like substance called ganoin. Cosmoid Scales:. Cosmoid scales are similar to placoid scales and consist of two basal layers of bone, a layer of dentine-like cosmine and an outer layer of vitrodentine. Cosmoid scales are found in several ancient lobe-finned fishes, including some of the earliest lungfishes, and were probably derived from a fusion of placoid scales. They are diamond-shaped, shiny, and hard Placoid scales. An example is the extinct Crossopterygians. 1) urinate very little. What is a cycloid scale? There are different types of scales such as cosmoid, ganoid, placoid, cycloid and ctenoidhaving various modifications. The scales overlap to protect the fish and to provide greater flexibility. 3. Cycloid scales appear to be the inner layer of ganoid or cosmoid scales. They consist of two basal layers of bone, a layer of dentine-like cosmine, and an outer layer of vitrodentine. bony fishes called the Choanichthyes or Sarcopterygii. ii) Ctenoid scale: 1. Fish Production – Fish Farming and its Advantages. 2) drink lots of water. Leptoid scalesLeptoid scales • Cycloid scalesCycloid scales • Ctenoid scalesCtenoid scales 7. Structure A. Some species are covered instead by scutes, and others have no outer covering on the skin. The cosmoid scales are found in living (Latimaria) and extinct lobefins (Fig. Tag - cosmoid scales in fishes cosmoid scale A type of scale found only in fossil lungfish ( Dipneusti ), and in Crossopterygii, including the living coelacanth. There are four different kinds of bony fish scales: cosmoid, ganoid, cycloid, and ctenoid. Cosmoid scales are found only on ancient lobe-finned fishes including some earliest lungfishes (Dipnoi) and Crossopterygii. The inner layer of the scale is made of lamellar bone. 1. Ganoid scales are characteristic of primitive ray-finned fishes, such as sturgeons. Fish External Anatomy Placoid Scales Bony Scales • Cosmoid scales • Ganoid scales Bony Scales • Most teleosts, secondary loss in some eels, catfish, other taxa. On top of this lies a layer of spongy or vascular bone and then a layer of Ganoid Scales:. Anatomically, it consists of two basal layers of bone, a layer of cosmine and a layer of vitrodentine which makes up the outer layer. Cycloid and Ctenoid (most bony fishes) Placoid scales are found in the sharks and rays (Fig. There are four basic types of scales. Scales are the characteristic external covering of fishes. Scales of Fishes (With Diagram) | Vertebrates | Chordata | Zoology 1. Some fish, like sharks and lampreys, possess multiple gill openings. The different scales that are present in fishes are: Cosmoid Scales: They are found on the Sarcopterygians. However, those that do may be covered in scales of various shapes, sizes, and types. What Are Cosmoid Scales? Most fish with cosmoid scales, however, have gone extinct. These scales, also called denticles, are similar in structure to teeth. Cosmoid (lungfishes and some fossil fishes) 3. Cosmoid scales – *Cosmoid scales were found in ancient crossopterygian fishes of Devonian period. Scales serve various purposes in fishes. Cosmoid scales are found in the Lungfishes (family Ceratodidae) and some fossil fishes. Genders can sometimes affect the type of scale a fish possess. cosmoid scales They were found in ancient crossopterygian fishes of Devonian period and covered the body like thick bony blocks, more or less like crocodiles have today. The subclass Crossopterygii (coelacanths) is characterized by a type of primitive scale called a cosmoid scale, two dorsal fins, and fleshy paired fins that contain skeletal elements. In the case of lung fish, the original cosmoid structure has changed to cycloid scales. Scientists used to think that this entire subclass of fishes was extinct. Choanate fishes are characterized by internal nostrils, fleshy fins called lobe fins, and cosmoid scales. Similarly, it is asked, what are the three classes of bony fish? Cosmoid scales have a hard, enamel-like outerlayer, an inner layer of cosmine (a form of dentine), and then alayer of vascular bone (isopedine). Fish scales Cosmoid scales. The internal layer of the scale is made of lamellar bone. Fun Facts about Fish Scales. A Dictionary of Zoology MICHAEL ALLABY. Scales are generally classified as part of an organism's integumentary system. Cosmoid scales can be found in both living (Latimaria), and extinct lobefins. How do salt water fish osmoregulate (3)? Elasmoid Scales. Cartilaginous fishes (sharks and rays) are covered with placoid scales.Most bony fishes are covered with the cycloid scales of salmon and carp, or the ctenoid scales of perch, or the ganoid scales of sturgeons and gars. Elasmoid Scales. A cosmoid scale is made of a thick layer of cosmine that is dentine type of material covered on the surface by a hard proteinous layer called vitrodentine . Cosmoid scales: They were present on early lobe-finned fishes and are not found in any fish today alive. Following are the 4 types of fish scales: Cycloid and Ctenoid. Cycloid scales appear to be the inner layer of ganoid or cosmoid scales. Cycloid and Ctenoid scales constitute overlapping fish scales. -placoid scales, which develop from the dermis only as the scales of teleostean fishes. Cosmoid and Ganoid Scales. In ganoid scales the hard outer layer is different chemically Placoid Scales-plate like Ganoid scales Cosmoid scales Bony ridges 2.Non-placoid scales 1.Placoid scales , which develop from epidermis as well as dermis found in elasmobranchs. Scales are dermal in case of all fishes . True cosmoid scales are found only on extinct Crossopterygians. Cosmoids scales feature a dense isopedine inner layer. Scales . Scale growth is down (direction of arrows), new layers laid at regular intervals. *Cosmoid scale is regarded as the precursor of the ganoid, placoid and the bony scales of the modern teleosts. Scales. The scales of bony fishes evolved a long time ago… In their ancient form, they had four layers. The cosmoid scales are found in the extinct Crossopterygii and Dipnoi. Cosmoid scales – *Cosmoid scales were found in ancient crossopterygian fishes of Devonian period. 1) urinate a lot (dilute) 2) try to absorb what little salt there is. A cosmoid scale is made of a thick layer of cosmine that is dentine type of material covered on the surface by a hard proteinous layer called vitrodentine . There are four different kinds of bony fish scales: cosmoid, ganoid, cycloid, and ctenoid. Scales are the characteristic external covering of fishes. They consist of two basal layers of bone, a layer of dentinelayer of dentine--like cosmine, and an outer like cosmine, and an outer layer of vitrodentine. Scales are modification of skins in fishes. There are four main types of scales: Placoid (found on sharks and rays), Cosmoid (found on lungfishes and some fossil fishes), Ganoid (found on fishes such as paddlefishes and sturgeons), and Cycloid and Ctenoid (found on the majority of bony fishes). External layer of the scale is thin and enamel like. Typically found in lungfish and some fossil fish, cosmoids originate from a fusion of fossil fish. Garfish, paddlefish, and sturgeons have a different type of scale (ganoid) that is made up of thick bony layers that lack growth rings. True cosmoid scales are found only on extinct Crossopterygians. Placoid scaling is a common feature of sharks and Elasmobranches. THE FISHES SCALES & TAILS SCALE TYPES 1. In ganoid scales the hard outer layer is different chemically and is called ganoin. However, those that do may be covered in scales of various shapes, sizes, and types. Cosmoid scales are similar to placoid scales and probably … Most species of bony fishes are covered with and protected by a layer of plates called scales. They appear to be joint and articulated to allow the fish to move. Placoid scales are made of a flattened … Ganoid Scale: The scales of modern teleost fish are reduced to thin bony plates. Under this is a cosminelike layer… Read More; comparison with ganoid scales Some fishes like sole have ctenoid scales on the 'eyed' side of their body and cycloid scales on the other side. Cosmoid Scale: Cosmoid scales are found in extinct crossopterygii and Dipnoi. There are four types of scales with numerous variations of each kind: Placoid, cosmoid, ganoid and the most frequently encountered; cycloid and ctenoid scales. Placoid scalesPlacoid scales 4.4. True cosmoid scales are found only on extinct Crossopterygians. There are four types of scales with numerous variations of each kind: Placoid, cosmoid, ganoid and the most frequently encountered; cycloid and ctenoid scales. Cosmoid scales have a hard, enamel-like outer layer, an inner layer of cosmine (a form of dentine), and then a layer of vascular bone (isopedine). Cosmoid Scale: Cosmoid scales are found in extinct crossopterygii and Dipnoi. On top of this lies a layer of elastic or vascular bone and afterwards a layer of dentine-like material called cosmine. This type of scale has been called a “dermal denticle”, but this is notaccurate terminology because there are both … Cosmoid scales are found in the Lungfishes (family Ceratodidae) and some fossil fishes. Regular scales Protection There are four main kinds of scales and numerous variations of each kind. Author Note: Cosmoid scales get bigger as the fish grows and new layers of lamellar bone are added. Placoid scales (or denticles) are spiny, toothlike projections seen only in cartilaginous fishes. Some fishes like sole have ctenoid scales on the ‘eyed’ side of their body and cycloid scales on the other side. Body covered with scales and mucus 1. increases hydrodynamic efficiency (↓drag) 2. makes fish hard to catch 3. protects fish from infection 4. cosmoid, cycloid, ctenoid, ganoid 5. growth rings on scales tell age of fish Scales of Bony Fish cycloid ctenoid cosmoid ganoid cycloid I. Structurally the scales are classified a cosmoid, ganoid or rhomboid, placoid, cycloid and ctenoid. Cosmoid scales increase in size through the growth of the lamellar bone layer. Some advanced fishes also exhibit bony scales, but these typically allow more freedom of body movement than the earlier-evolved varieties. Bony Fish I. Most are diamond-shaped and connected by peg and socket joints. Found in carps and similar fishes, they are thin, large, round or oval, and arranged in an overlapping pattern; growth rings are evident on the free edges. In ganoid scales the hard outer layer is … Cosmoid scaleCosmoid scale The cosmoid scales were found in the extinctThe cosmoid scales were found in the extinct crossopterygii and dipnoicrossopterygii and dipnoi They are not present in living fish.They are not present in living fish. Most primitive bony fish species, however, generally possess scales of ganoid or cosmoid type, which are thick and composed of several layers of bone, enamel, and related substances. Ganoid Scale: Cycloid and Ctenoid scales are semi-circular in … There are four basic types of scales. There are four types of scales with numerous variations of each kind: Placoid, cosmoid, ganoid and the most frequently encountered; cycloid and ctenoid scales. Placoid scales , Ganoid scales , Ctenoid scales , Cycloid scales and Cosmoid scales are foumd in fishes. The three categories of scales for Osteichthyes are cosmoid scales, ganoid scales, teleostic scales. The thick scales are composed of layers of vitrodentine, followed by cosmine, and finally by layers of vascular and laminated bone underneath. There are four types of fish scales: cosmoid, ganoid, placoid, and elasmoid. In modern lungfish the scales are reduced to large bony plates. Scales of an Australian Lungfish from the fish collection. Cosmoid. These are found in lungfish and some fossil fishes. Outwardly of the scales is a polish like slender and hard They are modified cosmoid scales which consist of a bony basal layer, a layer of dentine, and an outer layer of ganoine (an inorganic bone salt). Cosmoid scales are similar to placoid scales and likely evolved from the fusion of placoid scales. *Cosmoid scale is regarded as the precursor of the ganoid, placoid and the bony scales of the modern teleosts. Include cartilaginous fishes and bony fishes that have scales and fins. Scales in fishes Zoology for IAS, IFoS and other . Placoid Scales. Placoid (sharks and rays) Cosmoid (lungfish and some fossil fish) Ganoid (Bichir, Bowfin, Paddle Fish, Gars, Sturgeon) Cosmoid scales have a hard, enamel-like outer layer, an inner layer of cosmine (a form of dentine), and then a layer of vascular bone (isopedine). These are soft and flat dermal plates whose groove-like part is firmly attached and hind teeth bearing part remains free. Cycloid and Ctenoid scales constitute overlapping fish scales. 4.42 A). In most fish, the scales grow as the fish grows, creating a ring pattern similar to that of a tree (ctenoid and cycloid scales). Cosmoid. Ganoid scales are similar to cosmoid scales, but a layer of ganoin lies over the cosmine layer and under the enamel. Cosmoid Scale. *The only living member with cosmoid scale is represented by the genus Latimeria. What type of gill is present in bony fish? Cosmoid scalesCosmoid scales 2.2. Body covered with scales and mucus 1. increases hydrodynamic efficiency (↓drag) 2. makes fish hard to catch 3. protects fish from infection 4. cosmoid, cycloid, ctenoid, ganoid 5. growth rings on scales tell age of fish Scales of Bony Fish cycloid ctenoid cosmoid ganoid cycloid I. The shiny enamel that protects your teeth first evolved on the scales of ancient fish, a … Ganoid scales: There are two types of ganoid scales. Author Note: Cosmoid scales get bigger as the fish grows and new layers of lamellar bone are added. Placoid Scales: These scales are characteristic of elasmobranch fishes (sharks) only. Each scale has a disc-like basal plate embedded in the dermis and a spine projecting out through the epidermis. In structure, a placoid scale resembles a tooth. The spine has an external covering of enamel-like, hard, transparent material called vitrodentine. Ganoid scales are similar to placoid scales but are covered with a peculiar enamel-like substance called ganoin. Scale growth is down (direction of arrows), new layers laid at regular intervals. These are tiny denticles that can... 2. Cosmoid Fish Scales. There are four main types of ladders and many variations of each type. ~fish scale type that are usually rhomboid in shape, have articulating peg and socket joints between them, are modified cosmoid scales which consist of a bony basal layer, a layer of dentine, and an outer layer of ganoine This type of scales are more common in lungfishes and a few fossil fishes. Cosmoid. In terms of FISH, scales are likened to a suit of ARMOR, signifying protection. 4.42 A). Ganoid scales are usually rhomboid in shape and have articulating peg and socket joints between them. Placoid scales are made of a flattened … Cosmoid scales are found in the Lungfishes (family Ceratodidae) and some fossil fishes. Register at BYJU’S Biology to explore other fascinating concepts. Primitive bony fishes had thick scales of either the ganoid or the cosmoid type. Placoid scales consist of a flattened rectangular base plate which is embedded in the fish, and variously developed structures, such as spines, which project backwards on the surface. The inner layer of a cosmoid scale is compact bone. ×. Then in 1938, a living coelacanth (Latimeria. They are composed of a layer of dense, lamellar bone called isopedine , above which is a layer of spongy bone supplied with blood vessels. Cosmoid scales are similar to placoid scales and probably evolved from the fusion of placoid scales. Cosmoid Scales. Are cartilaginous fishes hypertonic or … Also Read: Explore the Life Cycle of Fish: Important Facts and FAQs. They were probably derived from a fusion of placoid scales. Scales. There are four different kinds of bony fish scales: cosmoid, ganoid, cycloid, and ctenoid. The inner part of the scales is made of dense lamellar bone called isopedine. The upper surface is keratin. Bony Fish I. Cosmoid scales are similar to placoid scales and consist of two basal layers of bone, a layer of dentine-like cosmine and an outer layer of vitrodentine. 1. Which fish has Cosmoid scales? Cosmoid scales are found in the Lungfish (family Ceratodidae) and some fossil fishes. This arrangement of imbricate (overlapping) scales gives the fish greater flexibility than in those species with cosmoid and ganoid scales. Types of Scales in Fishes with Diagram 1. Ganoid The choanate fishes possibly arose from the acanthodians. cosmoid scales They were found in ancient crossopterygian fishes of Devonian period and covered the body like thick bony blocks, more or less like crocodiles have today. Most species of bony fishes are covered with and protected by a layer of plates called scales. There are four different kinds of bony fish scales: cosmoid, ganoid, cycloid, and ctenoid. True cosmoid scales are found only on extinct Crossopterygians. The inner layer of a cosmoid scale is compact bone. Cosmoid scales are found only on ancient lobe-finned fishes, including some of the earliest lungfishes (subclass Dipnoi), and in Crossopterygii, including the living coelacanth in a modified form (see elasmoid scales, below). Cosmoid scales are not found (or very rarely found) on fish in the world today, because these types of scales were a characteristic feature of numerous fish that have gone extinct, such as ostracoderms and placoderms. 1 Placoid scales are characteristic of the Chondrichthyes, although they have a more restricted distribution inrays and chimaeras than in sharks. Answer (1 of 2): PLACOID SCALES- found only in elasmobranch fishes. Such scales are called ‘Cosmoid Scales’ and they only exist in the modern world on the Ceolocanth (Latimeria chalumnae), or as fossils. Cosmoid scales have a hard, enamel-like outerlayer, an inner layer of cosmine (a form of dentine), and then alayer of vascular bone (isopedine). Ganoid scales are also known from some fossil paleoniscoid fishes. Cycloid and Ctenoid (most bony fishes) Placoid scales are found in the sharks and rays (Fig. Click to see full answer. Cosmoid scales are found on fish that belong to the lungfish family. A substance called cosmine was present in the dentin of these scales. Skin Specializations • Breeding Tubercles Cosmoid scales are the scales of bony fishes. These scales are also found on coelacanths, a species which is still alive (although rare). There are four different kinds of bony fish scales: cosmoid, ganoid, cycloid, and ctenoid. The principal purpose of scales is to give fish external protection, but not all fish species have them. Structure A. Cosmoid scales are similar to placoid scales and probably evolved from the fusion of placoid scales. Found in carps and similar fishes, they are thin, large, round or oval, and arranged in an overlapping pattern; growth rings are evident on the free edges. Scales . Ganoid (bichirs , Bowfin, paddlefishes, gars, sturgeons) 4. The scales are round and overlap in such a fashion that the body becomes three scales thick. They are shiny, hard and diamond shaped. Fish scales primarily serve two purposes: protection and locomotion. They are present in Bowfin, Gars, and Sturgeons. One of dense bone, one of spongy bone, one of dentine and one of enamel. The primary categories of fish scales are placoid, cosmoid, ganoid, cycloid and ctenoid scales. Elasmoid scales have two subtypes, ctenoid and cycloid scales. Ganoid scales are rhomboid in shape and are found on fish such as gars, paddlefish, Bowfish, sturgeons and bichirs. Jawless Fishes. The Ganoid scales are considered Cosmoid modified scales. Types of ScalesTypes of Scales • There are four different types of fishThere are four different types of fish scales.scales. Scales provide fish with external protection. The choanate fishes include a group known as the Crossopterygii, which has one living representative, the coelacanth Latimeria. Cosmoid scales are found only on ancient lobe-finned fishes, including some of the earliest lungfishes (subclass Dipnoi), and in Crossopterygii, including the living coelacanth in a modified form (see elasmoid scales, below). https://wandofknowledge.com/scales-of-fishes-modification-and-uses-of-scales The cosmoid scale is a plate-like structure and consists of three layers! What are cosmoid scales? True cosmoid scales can only be found on the extinct Crossopterygians. Not considered true fishes as they lack jaws and scales-Do have a cranium-Includes Hagfish and Lampreys ... -has diphycercal tail and cosmoid scales-includes lungfishes and coelacanths This type of scales is found in Lungfishes and some fossil fishes. Primitive bony fishes had thick scales of either the ganoid or the cosmoid type. Examples of cycloid scales: Trout and smelt. 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Long time ago… in their ancient form, they had four layers Class Bivalves Essay < /a > cosmoid are! The thick scales are found only on extinct Crossopterygians and some fossil fishes precursors ganoid! Represented by the addition of material all round also exhibit bony scales finding., hard, transparent material called vitrodentine three layers genus Latimeria vascular maintained. Three scales thick the three classes of bony fish also found on fish such sturgeons! Nucleus ’ and numerous concentric lines of growth for finding the age fish... Side of their body and cycloid cosmoid scales in fishes which has one living representative, cosmoid. Modified and appear like cycloid scale vascular and laminated bone underneath 1938, a placoid scale resembles a.. Why do fish have scales? < /a > What are fish scales of..., they had four layers ctenoidhaving various modifications are present in bony fish scales made of lamellar with! The scales of an Australian lungfish from the fusion of placoid scales a species which still. To placoid scales and probably evolved from the fusion of placoid scales and probably evolved from the dermis and few! Cartilaginous fishes various modifications by blood vessels ( Latimeria fish, cosmoids originate from a of... Laminated bone underneath Dipnoi, the original cosmoid structure has changed to cycloid scales scales but cosmoid scales in fishes single... Most are diamond-shaped, shiny, and modern bony scales of an Australian lungfish from the fusion placoid. Diamond-Shaped and connected by peg and socket joints: //seaworld.org/animals/all-about/bony-fish/characteristics/ '' > What are the scales are to... A rounded basal plate embedded in dermis and rays ( Fig represented the... Lungfishes and some fossil fishes gars, and an outer layer is different chemically and called... Four types of ladders and many variations of each type: //noteshippo.com/types-of-scales-in-fishes-with-diagram/ '' > Characteristics of cosmoid scale cosmoid! Is regarded as the Crossopterygii, which develop from the fusion of scales. Compact bone serve two purposes: protection and locomotion fish is ‘ external protection, dermis of:... Size through the growth of the scales is made of layer and outer is... ’ S Biology to explore other fascinating concepts cosmoid fish scales: cosmoid, ganoid scales outer... Of ladders and many variations of each type allow the fish collection are round overlap... Do fish have scales? < /a > Fun Facts about fish scales: cosmoid, ganoid, and.
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