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Differences Between DF and AWF

2.7 Attack Performance Metrics

3.2.3 Differences Between DF and AWF

of a scaleless fish.

1. Operculum1. Operculum 10. Lateral line10. Lateral line

2. Cephalo- muchal shield 2. Cephalo- muchal shield 11. 11. Pelvic finPelvic fin

3 Dorsal spine 3 Dorsal spine 12. Pectoral spine 12. Pectoral spine

4. Dorsal filament4. Dorsal filament 13 pectoral fin13 pectoral fin

5. Dorsal fin5. Dorsal fin 14 Humeral process14 Humeral process

6. Adipose fin 6. Adipose fin 15 maxillary barbel15 maxillary barbel

7. Caudal pedunle7. Caudal pedunle 16 Outer mandibular 16 Outer mandibular barbel

barbel

8. Caudal fin 8. Caudal fin 17 Inner mandibular 17 Inner mandibular barbel

barbel

The external feature of a scaly The external feature of a scaly

fish.

fish.

1. Dorsal fin 1. Dorsal fin 6. Lateral line6. Lateral line

2. Adipose fi2. Adipose fi 7. Pelvic fin7. Pelvic fin

3. Dorsal spine3. Dorsal spine 8.Pectorial fin8.Pectorial fin

4. Caudal peduncle4. Caudal peduncle 9.Operculum9.Operculum

5. Anal fin5. Anal fin

FISH ANATOMY FISH ANATOMY

The Basic Structure of a Fish The Basic Structure of a Fish

Like most animals, the fish Like most animals, the fish

has a body which includes has a body which includes

the head, the trunk and the the head, the trunk and the

limbs. The body has limbs. The body has

generally an elongated generally an elongated

shape.

shape.

The head, the trunk and the tail The head, the trunk and the tail

follow each other without any follow each other without any

separation, which enables the fish separation, which enables the fish

to wriggle easily in the water.

to wriggle easily in the water.

Limbs are fins. The body is Limbs are fins. The body is

covered with the skin.

covered with the skin.

The Head The Head

In the front part of the In the front part of the

head is the mouth, of head is the mouth, of

which the shape and which the shape and

features differ according features differ according

to the feeding habits of to the feeding habits of

the fish.

the fish.

Some fish have large mouths Some fish have large mouths

with sharp teeth for seizing with sharp teeth for seizing

prey while others have small prey while others have small

mouths on the under surface mouths on the under surface

of the head, suitable for of the head, suitable for

scrapping up algae from the scrapping up algae from the

bottom.

bottom.

MOUTH

The shape of the teeth The shape of the teeth

depends also on the feeding depends also on the feeding

habits of the fish. Predatory habits of the fish. Predatory

fish, such as the fish, such as the

Hydrocynus are well Hydrocynus are well

supplied with sharp teeth.

supplied with sharp teeth.

TEETH

Vegetation eating fish may Vegetation eating fish may

have teeth, each one with have teeth, each one with

many more or less rounded many more or less rounded

points, arranged in bands points, arranged in bands

along the side of the jaws along the side of the jaws

(Tilapia rendalli).

(Tilapia rendalli).

The teeth of some omnivorous The teeth of some omnivorous

fish (Alestes) are quite similar to fish (Alestes) are quite similar to

the molars of man. In many the molars of man. In many

fishes, there is, in addition, a bony fishes, there is, in addition, a bony

plate bearing teeth in the back of plate bearing teeth in the back of

the throat which are called the throat which are called

pharyngeal teeth (Tilapia, Carp).

pharyngeal teeth (Tilapia, Carp).

Nostril Nostril

On the snout, above the On the snout, above the

mouth, are the nostrils. The mouth, are the nostrils. The

nostrils are not used for nostrils are not used for

breathing but only for breathing but only for

smelling.

smelling.

Barbel Barbel

Some fish have filaments along the Some fish have filaments along the side of their mouth which can be

side of their mouth which can be

longer, than the head itself (catfish) longer, than the head itself (catfish)

which are called barbels. Their which are called barbels. Their

number can vary within the range of number can vary within the range of

2 to 8. They are sensory organs 2 to 8. They are sensory organs

which help the fish to find its food.

which help the fish to find its food.

Opercula Opercula

At the hind end of the head At the hind end of the head

are two bony flaps called are two bony flaps called

opercula or gills covers, opercula or gills covers,

which can be lifted;

which can be lifted;

underneath are the gills.

underneath are the gills.

Gills Gills

Every gill is made of a bony Every gill is made of a bony

arch carrying long red arch carrying long red

filaments

filaments on one side called on one side called the gill filaments and short the gill filaments and short

teeth like, or longer comb like teeth like, or longer comb like

projections on the other side projections on the other side

called

called gill rakersgill rakers. .

The gill filaments are the The gill filaments are the

breathing organs of the fish, breathing organs of the fish,

the gill rakers are used as a the gill rakers are used as a

strainer to sieve out food strainer to sieve out food

particles from the water

particles from the water

The trunk The trunk

The trunk is the part of the body The trunk is the part of the body

in which are located a number of in which are located a number of

organs: the air bladder, the organs: the air bladder, the

stomach, the intestine, the liver, stomach, the intestine, the liver,

the kidneys, the ovaries, the the kidneys, the ovaries, the

testicles. It starts from the head testicles. It starts from the head

and includes the ventral cavity.

and includes the ventral cavity.

The tail – caudal fin The tail – caudal fin

It is located behind the anus It is located behind the anus

and ends with the caudal and ends with the caudal

fin. An anal fin and fin. An anal fin and

sometimes a part of the sometimes a part of the

dorsal fin can be found on dorsal fin can be found on

the tail.

the tail.

The fins The fins

When identifying a fish, the When identifying a fish, the

fins are the first things, which fins are the first things, which

should be examined. The should be examined. The

number of fins, their types, number of fins, their types,

sizes, situtation on the body sizes, situtation on the body

and position in relation to each and position in relation to each

other, are most important.

other, are most important.

The fins are similar to paddles The fins are similar to paddles

made out of rays which would made out of rays which would

be joined together by a web.

be joined together by a web.

The rays can be either spiny or The rays can be either spiny or

soft, ramified into a paint-brush soft, ramified into a paint-brush

and are then called soft rays.

and are then called soft rays.

Types of Caudal Fins Types of Caudal Fins

The caudal fin or tail of most The caudal fin or tail of most

fish is

fish is lobedlobed, which means that , which means that it is

it is forkedforked and has the upper and has the upper and lower lobes attenuated to and lower lobes attenuated to

points. But in some fish, it is points. But in some fish, it is

round

round, pointed, pointed or truncated or truncated. .

Adipose Fin Adipose Fin

Some species of fish have two Some species of fish have two

dorsal fins, the second of dorsal fins, the second of

which is often an adipose fin, which is often an adipose fin,

composed only of soft, fleshy composed only of soft, fleshy

tissue and usually without rays tissue and usually without rays

of any kind.

of any kind.

Body Body Forms Forms

Commonly, the fish body is torpedo-Commonly, the fish body is torpedo-shaped (

shaped (fusiformfusiform), and most often ), and most often slightly to strongly

slightly to strongly ovoid in cross ovoid in cross section

section. In free swimming species, the . In free swimming species, the body approximates the theoretically

body approximates the theoretically perfect

perfect streamline formstreamline form in which the in which the

greatest cross section is located close greatest cross section is located close

to 36 percent of the length back from to 36 percent of the length back from

the anterior tip the anterior tip

globe shapes (globiformglobe shapes (globiform – e.g. – e.g.

puffers, tetraodontidae) puffers, tetraodontidae)

serpentine (anguilliformserpentine (anguilliform – e.g. – e.g.

eels,

eels, anguillidaeanguillidae), ),

threadlike in outline (filliformthreadlike in outline (filliform e.g. e.g.

snipe eels, Nemichthyidae).

snipe eels, Nemichthyidae).

CompressedCompressed: flattened but : flattened but greatly elongated

greatly elongated

TrachipteriformTrachipteriform: flattened from : flattened from top to bottom

top to bottom

DepressedDepressed – the skates, – the skates, rajidae, and the batfishes rajidae, and the batfishes

FISH

FISH