3Fish can be described as Multicellular organismsOrganisms which live in fresh, salt or brackish waterHeterotrophicHaving gills, fins and usually scalesHaving jawsExhibiting a skeleton composed of bone or cartilage
4SkeletonFish may have an internal skeleton which consists of bone, cartilage, or a combination bone and cartilage
5Jaws: true or lacking?True jaws are lacking in the photo of the fish seen hereIt is called a round-mouthed fish, or jawlessHagfish and lamprey are classified as Cyclostomata (round mouth) or Agnatha (jawless)Most fish have true jaws
6Terminal and ventral mouths Mouth is considered ventral if located on the belly side of the fishIf the mouth is located at the most forward region, it is terminal
9Fins Single fins Dorsal Paired fins Caudal Anal Pectoral fins AnteriorAdipose/PosteriorCaudalAnalPaired finsPectoral finsPelvic fins
10Caudal finThe caudal fin (tail fin) vary tremendously among the fishes of the world.The two major types of caudal fins areHomocercal- top and bottom half are about the sameHeterocercal- top portion is much larger than bottom half
11Homocercal or heterocercal? Observe each tail and identify the type
12Caudal FinFish with streamlined bodies and a stiff, crescent-shaped caudal fin or tail, tend to move rapidly through the water by swishing their tail from side to side.This action propels the fish much like sculling (rowing a boat with an oar) propels a boat.
14Fish ScalesScales and slime help to protect the fish from other organismsThere are four main kinds of scales, and numerous variations of each kindPlacoid 1CosmoidGanoid 2Cycloid and Ctenoid 3 and 4
15Scales have a particular feature: they possess concentric patterns looking like the tree rings you can see on cut tree trunks. ...But scales are permanent on fish skin: they don't fall like tree leaves so they can to be used to calculate a fishes age. But fish growth can be irregular (e.g. females stop growing while reproducing...) and a laboratory study of each species is necessary to correlate the rings with real age. If you mount scales on a slide and look through them toward a light source, you can see some iridescence (rainbow colors) because light is diffracted light by the scale rings.
16Ctenoid scalesAbove: sole scale. Below: sea perch.
17How old is a fish scale?As cycloid and ctenoid scales increase in size, growth rings called circuli become visible.By counting the annuli it is possible to estimate the age of the fish.These rings look a little like the growth rings in the trunk of a tree. During the cooler months of the year the scale grows more slowly and the circuli are closer together leaving a dark band called an annulus.
18Other facts about scales Can a fish have more than one type of scale?Yes. Some species of flatfishes (flounders, soles, etc) have ctenoid scales on the eyed side of the body and cycloid scales on the blind side.Can scale type vary with sex?Yes. In some species of flatfishes (flounders, soles, etc) the males have ctenoid scales and the females have cycloid scales.
19Body shapes of fish Fusiform (torpedo-shaped) Depressed dorso-ventrallyCompressed laterallyElongated, eel-likeGlobiform, spherically shapedTruncate
26Markings and coloring of fish Counter-shadingSpottedStripedBandedBarred“See me”
27Nurse SharkThe upper surface of the body is yellow-brown to gray-brown. The remainder of body is a lighter shade of the same color.
28Striped Hawaiian Squirrelfish Hawaiian Squirrelfish Distribution: Endemic to the Hawaiian Islands and Johnston AtollRemarks: This is the most abundant squirrelfish on Hawaiian coral reefs. Squirrelfishes are nocturnal; spending the daylight hours in caves and emerging at night to forage for prey.Hawaiian Squirrelfish
29See Me!! photo courtesy of Richard L. Pyle Pseudanthias hawaiiensis Hawaiian Longfin Anthias Distribution: Endemic to the Hawaiian IslandsRemarks: Found most frequently in deeper waters around the Hawaiian Islands, this fish impresses the observer with its delicate long pelvic and anal fins streaming from under its body. The bright colors are not apparent at depth, but sparkle when illuminated with a dive light. Males are somewhat more colorful and larger than females, and males generally maintain large harems of females.Pseudanthias hawaiiensisphoto courtesy of Richard L. Pyle
39Blue Lined Triggerfish Pseudobalistes fuscus Beautiful, but very aggressive and very strong fishThey are deep and fat bodied with enlarged headsThey have very powerful jaws and can chew through just about anythingThe triggerfish takes its name from the locking mechanism of the stout first dorsal-fin spine and the smaller, slender second spine (the trigger). When the first spine is erected, the second spine is also pulled up and functions like a cam to wedge the larger spine in a vertical position (Fig. 1). The first spine cannot be folded down, until the tip of the second spine is pulled posteriorly. The family name Balistidae is formed from the genus name Balistes, which is derived from the Latin ballista, another name for the Roman catapult, in allusion to the trigger mechanism of the dorsal-fin spines. Most triggerfish species occur on coral reefs, and when threatened by a predator, triggerfish dart into a hole or crevice on the reef, lock their dorsal spine erect and depress their pelvic bone to wedge themselves into the reef. The body is also covered with strong, rough, plate-like scales that serve as armour plating and provide further protection.The pelvic fins are reduced to a small, bony nubbin at the tip of the long depressible pelvic bone on the ventral midline of the belly. Triggerfish swim by undulating the soft dorsal and anal fins, and use their tail fin only when they are in a hurry.Although the mouth is small, the jaws are provided with strong, sharp teeth, and triggerfishes can deliver a painful bite. They feed on a variety of benthic invertebrates, including crustaceans, molluscs, brittlestars, tunicates, polychaete worms, sponges, hydrozoans, tips of branching coral, and small fishes. Sea urchins are a favourite food, and even the long spines of Diadema urchins pose no problem for a hungry triggerfish. The fish just picks the sea urchin off the bottom, flips it over in midwater and then zeroes in on the spineless underside of the urchin. Some triggers, especially the redtooth (Odonus niger) and species of the genus Xanthichthys feed primarily on zooplankton.Triggerfish are closely related to the filefishes (Family Monacanthidae), and some filefishes also have a locking dorsal-fin spine. But filefishes have only one or two dorsal-fin spines, all the dorsal, anal and pectoral-fin rays are simple (unbranched), and the scales are modified, forming fine short bristles like on a toothbrush.Triggerfishes occur worldwide in tropical and warm temperate waters, generally near shore in relatively shallow water (usually less than 100 m), but adults of some species are regularly found out in the open ocean. Most triggerfish are good eating, although large specimens of some species are occasionally toxic and eating these fish may result in ciguatera poisoning.When it comes time for spawning, most triggerfish dig a shallow crater in the sand, where the female deposits the eggs. Both sexes have been reported guarding the nest until the eggs hatch and the larvae float away. Should you see a trigger circling a spot on the sand, chasing other fishes that approach this location and blowing jets of water at the spot, it is likely that the fish is guarding a nest there. Steer well clear of these nest guarders, as they are particularly aggressive, and have no hesitation in attacking and biting divers.
40Puffer Photo by ScubaMom Another defense which makes the Puffer not an ideal choice is that the flesh of the puffer is suffused with Tetrodotoxin. Tetrodotoxin is a powerful neurotoxin that can cause death in nearly 60% of the humans that ingest it. A human only has to ingest a few milligrams for a fatal reaction to the toxin to occur. Once consumed the toxin blocks the sodium channels in the nervous tissues, ultimately paralyzing the muscle tissue. Curiously, the toxin seems not to be synthesized by the fish itself, but by bacteria associated with the fish! The fish has a mutation in its own sodium channels which makes it resistant toPhoto by ScubaMom
41Tetraodontidae: Puffer Fish Body is cone-like with the widest end being the head, and the posterior tapering to the tail fin.When threatened, inflates its body by taking in air and water.Once “puffed,” it will float upside down until it can release the air.By swelling the puffer becomes too large to consume.Some Puffers also have small spines.Puffers have strong jaws and teeth fused into a parrot-like beak.
42Long Horned Cowfish Lactoria cornuta Cowfish are members of the Boxfish and Trunkfish families (Ostraciidae). All of these fish have rigid bodies made up of bony plates which cover them entirely except for the stomach. The only flexible part is the tail. Nature protects these slow, gentle fish by outfitting them with sharp spikes front and rear and by covering them with poisonous flesh.The Longhorned Cowfish is brilliant yellow in color with bright blue spots in the center of each piece of its body plating. They should not be kept with aggressive or fast moving fishes and their skin can be damaged by the attentions of cleaner fish. They are intolerant of each other and need enough room for each to establish it's own territory. They are generally compatible with invertebrates but may pick at tube worms.
44Orbiculate batfish Platax orbicularis Batfish are members of the Ephippidae family. Batfish are often recognized by their elongated fins, which are present in the younger stages. In the growing process the fins become shorter and the body grows longer. Batfish live in several different tropical and subtropical oceans around the world. Juvenile Batfish stay in the inshore waters. The larger Batfish can be found on or near coral reefs. Although age is a determining factor, some batfish can be found traveling in schools or as individuals.
45Jawfish Opistognathus sp. Great aquarium community fishMale is a mouth breeder
46Sargassum angler fish Histrio histrio Has its own fishing poleNot a strong swimmerLives in floating Sargasso weed
49Thresher shark feed primarily on small schooling fishes (such as herrings, sardines) that are herded together with their tails and then stunned or killed with it.
50Rays Rays are dorso-ventrally flattened Distinguished by disk shaped body, long-thick tail, and gillsbody is composed of a disk (head, trunk and pectoral fins )The ventral side (underside) is the location of the mouth and five pairs of gill slits.Spiracles are the 1st gill slits and the only ones located on the dorsal side.Eyes are located dorsally
51Atlantic Manta Manta birostris Plankton feederBecome very large
54Redfish The Redfish is notorious as a bottom feeding animal. It can also be seen on the surface, feeding on schools of fingerling baitfish. It prefers shallow grass beds and structures where small fish and crustaceans are abundant.
56Oyster Toadfish: Opsamus tau Bulging eyesFleshy flaps (whiskers) on cheeks and jawSkin is yellow to brown with dark brown oblique bars and brown reticulationsTail is long with tufted end.
57Oyster Toadfish Opsamus tau The oyster toadfish is very unique it has sound which make the oyster fish a subject of its share of studies of fish communication. the male produces a sound like a boatwhistle that is associated with mating and nesting. both males and the females make a grunting sound which appears to be aggresive and territorial in nature. the source of both these sounds is the toadfishes swimbladder, which contains a pair of the fastest contracting muscles in any animal. the sound producing structure is similar and the difference in sound made by the male and the female may result from neural and hormonal differences rather than the variations in structure of the swimbladder. this has puzzled scientist for years.
58Golden Butterfly fish Chaetodon semilarvatus Pectoral fins are enlarged and wing like. Dorsal fin located far to the rear of the body. Thread shaped elongated rays on their pelvic fins, which function as tactileTiger-like stripesTo an insect that suddenly finds itself the prey of a golden fish charging out of the water, the fish may look more like the tiger its stripes suggest rather than a butterfly. These fish are normally found in pairs, although in captivity, it is suggested that they not be kept in the same tank unless one is much smaller than the other. Some species appear to be monogamous. Courtship is enthusiastic, ending with mating at dusk. Butterfly fish are egg-layers, and the eggs develop free in the water without parental care. In many species of butterflyfish, the young are a different color from their parents. The young larvae are of a type unique to butterflyfish -- "tholichthys larvae" -- and look much like small insects themselves. The head is armored, with plates projecting from the head toward the back. These larvae grow to a few centimeters across and then transform into a tiny miniature of the adult.
59Golden Butterfly Fish Chaetodon semilarvatus Growing to around 8 inches at maturity, the golden butterfly fish (Chaetodon semilarvatus) is one of nature's unique beauties. As the name implies, they are a golden yellow color. Their pectoral fins are enlarged and wing like. Their head and back are flattened, with the dorsal fin located far to the rear of the body. They have thread shaped elongated rays on their pelvic fins, which function as tactile receptors. The scales of the butterfly fish lack ornamentation, however they appear to have tiger like stripes growing vertically along the middle of their body. Given the scientific name Chaetodon -- "bristle-toothed" -- the tigerish appearance may be warranted, and indeed these attractive fish are predators. The large pectoral fins of the butterfly fish allow them to "jump" up from the water and through the air, giving them the appearance of flying, thus the name "butterfly." The butterfly fish is generally found floating at the top of the water where it appears to hang from the surface. This makes it convenient for them to reach their food supply, which consists mainly of flying insects. To an insect that suddenly finds itself the prey of a golden fish charging out of the water, the fish may look more like the tiger its stripes suggest rather than a butterfly. These fish are normally found in pairs, although in captivity, it is suggested that they not be kept in the same tank unless one is much smaller than the other. Some species appear to be monogamous. Courtship is enthusiastic, ending with mating at dusk. Butterfly fish are egg-layers, and the eggs develop free in the water without parental care. In many species of butterflyfish, the young are a different color from their parents.
60Sergeant - Major Fish Abudefduf saxatilis Grows up to 8"(20cm)TL Lively coloredlaterally compressedBlack vertical stripes narrow toward the belly*dark spot at the base of the pectoral fin Small terminal mouth*five black bars that resemble the insignia of that rank the insignia of that rank in military services
61Scorpion fish:Stone fish Body length: 10 to 20 “Weight: 1 to 5 lbsLarge head, mouth and jaws, tapering to a small tailColor: red, orange, yellow, and black. Dorsal, pelvic, and anal fins have sharp spines with venom; venom glands lie alongside the spines. Irregular surface and patchy colors hide the fish's body contours and make it look like a patch of weed-covered rock.
62Garibaldi Hypsypops rubicundus Orange in colorSmall, narrow mouthRounded, somewhat oval shape. Tail is short, and heart shaped Stubby fins
63Archer Fish Toxotes jaculatrix The archer is capable of leaping 12 inches out of the water and catch prey in its mouth.It can also launch a jet of water out of its mouth, to knock down bugs flying or walking on the plants aboveLower lip protrudes over the upperThe Archer Fish has several amazing anatomical, physiological, and behavioral aspects.If you were to have an Olympic fish triathlon this fish would definitely win gold.The archer is capable of leaping 12 inches out of the water and catch prey in its mouth.It can also launch a jet of water out of its mouth, to knock down bugs flying or walking on the plants above. The archer picture to the right, the Archer fish uses its binocular vision to look for prey on or above the surface of the water. When the Archer prepares to launch water it uses the tongue and top of the mouth to form a longitudinal grove, similar to that of a rifle barrel. Once this groove is made the Archer can rapidly launch several squirts of water with compression of its gills to knock down prey. Archer have been observed knocking down small insects from up to 6 feet above the water surface.
64ARCHER FISH Toxotes jaculatrix The archer is capable of leaping 12 inches out of the water and catch prey in its mouth.It can also launch a jet of water out of its mouth, to knock down bugs flying or walking on the plants above. The archer picture to the right, the Archer fish uses its binocular vision to look for prey on or above the surface of the water. When the Archer prepares to launch water it uses the tongue and top of the mouth to form a longitudinal grove, similar to that of a rifle barrel. Once this groove is made the Archer can rapidly launch several squirts of water with compression of its gills to knock down prey. Archer have been observed knocking down small insects from up to 6 feet above the water surface. Archer Fish at the Fort Worth Zoo Photos above and below from Badman's Tropical Fish
65PinfishCommon in our Gulf this fish makes good bait!
69Paddlefish Polyodon spathula Its closest living relative, the more well-known sturgeon, the paddlefish is an ancient fish that has been cruising the rivers and tributaries of the Mississippi River system for hundreds of thousands of yearsAKA in AL: Spoon-billed catfishPrized for its excellent white meat and valuable roe, the paddlefish has been severely over fished. The taste is said to be similar to salmon or swordfish. The roe are important to the commercial caviar business. In fact, much of the caviar that is sold as sturgeon roe is actually paddlefish roe. Over-fishing, combined with changing habitats, has caused paddlefish numbers to drop. However, today many states, such as Alabama, Tennessee and Missouri, have tough laws protecting the paddlefish from over fishing and illegal roe collection. Many state agencies also breed and restock paddlefish into areas where they are no longer found. We hope that one day the waters of the Mississippi River System will find this unique natural treasure restored to its original numbers.
91Gafftopsail and hardtop catfish Males are mouth breeders
92Flathead catfish Pylodictis olivaris The barbels contain taste organs and thus in a sense are an extension of the tongue. This is logical since the majority of catfishes are active at dusk and at night and need a supplementary organ to detect food (Grzimek 363).
93Redtail Catfish Phractocephalus hemioliopterus World record- 97lb 7oz , in wild 110 lbs and 3ft to 5ftIn theory catfish are unable to use visual clues to track prey in their dark habitats so they follow recent chemical trails left behind by smaller fish like for instance guppies. The catfish use electrical field sensors to find the prey. These are called chemoreceptors. The chemoreceptors abound across the catfish's skin and act like big tongues as the catfish swim in the water.Source Materials and Related Links:Catfish Profile at:Catfish Profile at: freshaquarium.about.comUSGS: Red Tail Catfish at Nonindigenous Aquatic Species [NAS]
94Symbiotic relationship Stoplight Parrotfish and Clown Wrasse
95SeahorseProbably the fish that does not fir any descriptions other than “other” Male carries the eggs until they hatch in his brood pouch.
96Creatures of the Deep-Mesopelagic Here's an up close and personal view of the wicked-looking Viper fish (Chauliodus macouni).Check out the teeth and the bug eyes on this guy!
97Creature of the Mesopelagic depths A Fangtooth - scientists still aren't exactly sure why so many bony fishes of the deep have such enlarged, daggerlike teeth
98Other deep ocean fish, the gulper eel Gulper eels have a hinged skull, which can rotate upward to swallow large prey. The gulper eel is particularly well-known for its impossibly large mouthFish that live down here must adapt to a very low food supply, eating only "scraps" that sink down from above, or sometimes eating each other.
103Lantern fishLight producing spots on their bodies that light up the dark surroundingsShiny dots along the lower part of the body make light.Bioluminescence, the making of light by organisms, is very common in deep water.It serves many functions. Perhaps this fish uses light patterns as a means of recognizing its own kind in the dark.
111Lionfish Pterois volitans An extraordinary and decorative fish, the lionfish is immediately identified by its long, fanlike pectoral fins, branched dorsal fin and brightly striped body. This eye-catching coloration warns potential enemies that the lionfish's grooved spines are equipped with potent venom, which can have serious, perhaps fatal, effects, even in humans.
112 Snakehead fish A Fish Out of Water Reaching up to 40 inches in length and weighing up to 15 pounds, the formidable creature with snake-like scales on its head has an ability shared by only a few other species of fish — it can survive out of water.The fear is the animal could squirm from one body of water to another using its pectoral fins as limbs."They're not particularly fast, but they can move," says Eric Schwaab, director of the Maryland Fisheries department.Scwaab has posted wanted posters around the Maryland lake, identifying the snakehead fish and urging anglers to kill "by cutting/bleeding" any specimens they might catch. He and his team are also using traps baited with cat food to try and capture any lingering snakeheads in the pond.But an intense attack on the fish will have to wait until cooler fall and winter temperatures relieve the pond of a thick growth of lilies and weeds. Large nets would get snared in the plants and a technique known as electrofishing would also be hindered. Electrofishing involves running an electric current through the water, which stuns all fish and makes them float to the surface. Any northern snakeheads would then be collected and killed.