What is a Fish? Characteristics, features, examples of the animals with fins, gills, and scales www.winternet.com/~mikelr/ assets/Fish.jpg
Mar 26, 2015
What is a Fish?
Characteristics, features, examples of the animals with fins, gills, and scales
www.winternet.com/~mikelr/ assets/Fish.jpg
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Fish can be described as• Multicellular organisms• Organisms which live in fresh, salt
or brackish water• Heterotrophic• Having gills, fins and usually scales• Having jaws• Exhibiting a skeleton composed of
bone or cartilage
Skeleton
Fish may have an internal skeleton which consists of bone, cartilage, or a combination bone and cartilage
Jaws: true or lacking?
• True jaws are lacking in the photo of the fish seen here
• It is called a round-mouthed fish, or jawless
• Hagfish and lamprey are classified as Cyclostomata (round mouth) or Agnatha (jawless)
• Most fish have true jaws
Terminal and ventral mouths
• Mouth is considered ventral if located on the belly side of the fish
• If the mouth is located at the most forward region, it is terminal
Terminal mouth
Ventral mouth
Fins
• Single fins Dorsal
• Anterior• Adipose/Posterior
CaudalAnal
• Paired finsPectoral finsPelvic fins
Caudal fin
• The caudal fin (tail fin) vary tremendously among the fishes of the world.
• The two major types of caudal fins are– Homocercal- top and bottom half are
about the same– Heterocercal- top portion is much
larger than bottom half
Homocercal or heterocercal?
Observe each tail and identify the type
Bonnethead shark
Caudal Fin
• Fish 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.
Fish Scales
There are four types of scales with numerous variations of each kind:Placoid, cosmoid, ganoid and the most frequently encountered; cycloid andctenoid scales. Some fishes like sole have ctenoid scales on the 'eyed' side of their body and cycloid scales on the other side.
Fish ScalesScales and slime help to protect the fish from other
organisms
• There are four main kinds of scales, and numerous variations of each kind
1.Placoid 12.Cosmoid 3.Ganoid 24.Cycloid and Ctenoid 3 and 4
1 2 3 4
• Scales 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.
Ctenoid scales
Above: sole scale.
Below: sea perch.
How 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.
Other 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.
Body shapes of fish
Fusiform (torpedo-shaped)Depressed dorso-ventrally Compressed laterallyElongated, eel-likeGlobiform, spherically shapedTruncate
Fusiform
• Torpedo-shaped
Depressed
• Dorso-ventrally flattened
• Top to bottom
Elongate
• Eel-like, long bodyAlso,• Strong jaws• Muscular• Continuous fin
Compressed
• Laterally flattened • side to side
Globiform
• Spherical• Looks like a ball
Truncate
• Triangular
Markings and coloring of fish
• Counter-shading• Spotted• Striped• Banded• Barred• “See me”
Nurse Shark
• The upper surface of the body is yellow-brown to gray-brown.
• The remainder of body is a lighter shade of the same color.
Striped
Hawaiian Squirrelfish
See Me!!
Pseudanthias hawaiiensis
photo courtesy of Richard L. Pyle
Barred
• Bands that stop and do not go all around
Identify these markings
Anatomy of a bony fish
More on anatomy
Food chain
• Some fish eat other fish…
• which ate smaller fish…
• which may have eaten tiny fish, microscopic animals or plants
Fish may be eaten by
• Other fish• Birds such as this
Osprey• Raccoons• Bears• Cats• Humans
Fish Behavior: School or not to school?
• Some fish prefer to live singly, while others travel in schools
• A school of fish may appear as one large animal to other animals
Where in the water do fish live?
Fish can be observed in all parts of the water column
at the surfaceopen water habitats - pelagicbenthic
www.dkonline.co.uk/animal/
Blue Lined Triggerfish Pseudobalistes fuscus
• Beautiful, but very aggressive and very strong fish
• They are deep and fat bodied with enlarged heads
• They have very powerful jaws and can chew through just about anything
Puffer
Photo by ScubaMom
Tetraodontidae: 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.
Long Horned CowfishLactoria cornuta
Sturgeon
Orbiculate 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.
Jawfish Opistognathus sp.
• Great aquarium community fish
• Male is a mouth breeder
Sargassum angler fish Histrio histrio
• Has its own fishing pole
• Not a strong swimmer
• Lives in floating Sargasso weed
Bonnethead shark
Blacktip shark
Thresher 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.
Rays• Rays are dorso-ventrally
flattened• Distinguished by disk
shaped body, long-thick tail, and gills
body 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
Atlantic Manta Manta birostris
• Plankton feeder• Become very
large
Southern stingray
Spotted gar Lepisosteus oculatus
Redfish
• 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.
Red Snapper
• great eating• reef fish
Oyster Toadfish: Opsamus tau
• Bulging eyes • Fleshy flaps
(whiskers) on cheeks and jaw
• Skin is yellow to brown with dark brown oblique bars and brown reticulations
• Tail is long with tufted end.
Oyster Toadfish Opsamus tau
Golden Butterfly fishChaetodon 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 tactile
• Tiger-like stripes
Golden Butterfly FishChaetodon semilarvatus
Sergeant - Major Fish Abudefduf saxatilis
• Grows up to 8"(20cm)TL
• Lively colored • laterally
compressed • Black 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
Scorpion fish:Stone fish• Body length: 10 to 20 “ • Weight: 1 to 5 lbs • Large head, mouth and
jaws, tapering to a small tail
• Color: 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.
Garibaldi Hypsypops rubicundus
• Orange in color • Small, narrow
mouth • Rounded,
somewhat oval shape.
• Tail is short, and heart shaped
• Stubby fins
Archer 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
• Lower lip protrudes over the upper
ARCHER FISH Toxotes jaculatrix
Pinfish
• Common in our Gulf this fish makes good bait!
Lookdown
Blackfin tuna
Silver Seatrout
Paddlefish 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 years
AKA in AL: Spoon-billed catfish
Pirana
Spanish Mackerel
Striped anchovy
Triple Tail
Gulf menhaeden
Littlehead porgy
Yellowfin tuna
White Marlin
Swordfish
Dolphin (male)
Jack Crevalle
Bigeye jacks
Atlantic bumper
Atlantic croaker
Atlantic spade fish
Cobia
Barracuda
Florida pompano
Gulf flounder
Starry Flounder Platichthys stellatus
• left-eyed flounder
White and striped mullet
Gafftopsail and hardtop catfish
Flathead 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).
Redtail Catfish Phractocephalus hemioliopterus
World record- 97lb 7oz , in wild 110 lbs and 3ft to 5ft
Symbiotic relationship
• Stoplight Parrotfish and Clown Wrasse
Seahorse
Creatures 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!
Creature 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
Other 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 mouth
• Fish 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.
Bioluminescence is simply light produced by a chemical reactionIt
• The deep-sea fish Aristostomias has more than one light organ. The light produced by species like Malacosteus, Aristostomias, and Pachystomias has such long wavelengths that it is nearly infrared and is barely visible to a human eye. In addition, they can produce typical blue-green light from a separate organ.
(Illustration © Steven Haddock)
T h e B l a c k D r a g o n f i s h
Interested in Reading…
• Creeps from the Deep : Life in the Deep Sea by Norbert Wu (Illustrator), Leighton R. Taylor
$10.46
Abyssal Zone
• Abyssal ZoneSome of the strangest creatures on our planet live in the deepest zone. The water here is pitch black, and almost freezing; the pressure is immense.
Deep-sea angler fish
Lantern fish
Light producing spots on their bodies that light up the dark surroundings
Shiny 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.
Deep sea creature
Plastic pollution: Entanglement
• Six-pack rings cause problems for many organisms including birds, fish and mammals.
• Solution: cut them up before disposing
Fish Identification
To key a fishwww.amonline.net.a
u/fishes/ students/scales/
Interested in Fish???
Source of information
www.state.ia.us/.../fwb/fish/ programs/mgmt/surveys.htm
Sources
• Florida Fish and Wildlife Conservation
Commission http://floridaconservation.org • www.dkonline.co.uk/animal/ images
: www.heartlandhouse.com/images/
www.dkonline.co.uk/animal/ images
Lionfish 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.
Snakehead fish• http://abcnews.go.com/sections/scitech/DailyNews/
invasivefish020709.htmlhttp://abcnews.go.com/sections/scitech/DailyNews/invasivefish020709.html
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.
http://abcnews.go.com/sections/scitech/DailyNews/invasivefish020709