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Date & Time : 22, November 2024 10:00
General Characteristics of Pisces
Features of Fishes
Classification of Pisces
A Few Examples
1. Scoliodon
Common name - Dog fish
Habitat: Open sea
Distribution: Zanzibar to Ceylon,Ceylon to Malay Archipelago in Indian Ocean from Bay of Bengal,East Indies and the Philippine Islands ,from Mexico to Panama in Eastern Pacific ,from Labrador to Brazil in Atlantic ,from Cuba in West Indies and Eastern Coast of South America
Characteristic Features:
1.Body - long, laterally compressed ,spindle - shaped tapering at both ends.
2. Body Length - 30 to 60 cm
3. Body Colour - dark grey on dorsal and lateral surfaces and pale on ventral surface
4. Body Division - Head , Trunk and Tail
5. Dorso- ventrally compressed head with wedge - shaped snout in front
6. Largest part of the body is trunkextending from behind the gill - slits upto the cloacal aperture.
7. Tail lies behind the cloacal opening.
8. Eyes - large and circular , present at the side of the body
9.Mouth -wide crescentric opening , present on the ventral side of the head.
10. Gill - Clefts - 5 pairs , present on lateral sides
11. Median Fins comprises of :
a) 2 dorsal fins;
b) 1 caudal fin; and
c) 1 anal or ventral fin
12. First Dorsal Fin - triangular and present in front of the middle of the body
13. Second Dorsal Fin - triangular and small and present mid-way between the first dorsal and tail
14. Caudal fin present along the ventral and dorsal surfaces of Tail and forms dorsal and ventral lobe.
15. Anal fin present in the mid-ventral line. Length - 5 cm in front of caudal fin opposite to the second dorsal fin
16. Lateral Fins comprise of :
a) 2 pairs of Pectoral Fin
b) 2 pairs of Pelvic Fin
17. Pectoral Fins are large than pelvic fins
18. Pelvic fins has acopulatory organ in males called Clasper connected with its inner edge
19. An enlongated opening between the two pelvic fins called Cloacal Aperture
20. Lateral Line- a faint line running on either side of the body extending from head to the tail.
2.Sphyrna
Common name - Hammer-headed shark
Habitat: marine shark live in deep water
Distribution: Tropical and Sub- tropical seas
Importance: It is caught for oil but yield is low
Characteristic Features:
1.Body - elongated
2. Body Length - 4-5 cm
3. Hammer-shaped head i.e. head is flattened in front and expanded sideways into 2 conspicuous lobes
4. Mouth - Crecentric and ventrally situated
5. Nostrils present ventrally at the base of the lateral lobes
6. Gills-slits - 5 pairs and laterally present
7.Spiracles absent
8. Viviparous
9. Asterospondylus Vertebrae
10. Presence of 2 Dorsal Fin .First is situated in front of the pelvic fin and second is opposite to the Anal fin
11. Ferocious and attack its prey with its Head
3.Trygon
Common name - Sting ray or Whip-tailed ray
Food: Carnivorous. food contain crustaceans, molluscs, and small fishes
Distribution: Tropical part of Atlantic and Pacific Oceans including the Pacific coasts of North and South America
Importance: Flesh of the fish is edible and liver yield a fair amount of oil
Characteristic Features:
1. Flat body. Sub-Rhomboidal disc
2. Ventrally located mouth
3. Pectoral fins are confluent with the sides of head
4. Front of mouth has a rectangular naso-frontal flap.
5. On the dorsal side behind the eyes spiracles are present
6. On the ventral side five pairs of gill - slits are present
7. Long, slender whip-like tail terminating in a small caudal fin and armed with a serrated poisonous spine or string
8. In male claspers are present near the pelvic fin
9. Viviparous
10. It inflict wounds on its victim by means of string on the tail .
4.Pristis
Common name - Saw fish
Food: Predaceous. Food comprises small fishes and flesh of males and other marine animals
Distribution: Mediterranean and Atlantic Oceans particularly in America, West Indies, China and Gulf of Mexico. In India Pristis cuspidata and P. microdon species are found
Importance: Invaluable for liver oil of high vitamin value and skin for scale boards
 Sketchbook of fishes - 25. (Longnose) Saw shark - William Buelow Gould, c1832 Characteristic Features:
1. Body: elongated, depressed and shark - like
2. Length: 3-6 m or even long
3. Rostral tentacles absent
4. Skull and Head prolonged into a long flattenedrostrum, the lateral margins of which are provided with a series of strong tooth-like denticles giving appearance of saw
5. Minute and obtuse teeth in jaws
6. Behind the eyes spiracles are present
7. Large dosal fin, first dorsal fin is opposite to the pelvic fin
8. Well-developed tail and is terminating in heterocercal caudal fin
5. Torpedo (Astrape)
Common name: Electric Ray
Food:Carnivores. Food comprises of Crustaceans and Molluscs
Distribution: Mediterranean, Red sea, Atlantic and Pacific Oceans. Indian Ocean has T. marmorata species
Importance: Give heavy electric shocks
Characteristic Features:
1. Body: Flattened dorso-ventrally and sub-circular disc shaped
2. Smooth skin without scales
3. Anterior margin is semicircular which is upported by prenasal rostrum in centre and laterally by branched preorbital cartilage
4. Mouth: transverse and ventral
5. Quadrangular naso-frontal lobe present
6. Behind eyes spiracles present
7. Ventral gill-slits
8. In between the pectoral fins and head on either side - a pair of large eletric organs are present.
9. Viviparous
10. Tail: short and consist of :-
a) 2 dorsal fins
b) 1 caudal fin
6. Chimaera
Common name: Rat fish or King of herrings
Distribution: Coasts of Europe from Norway to Portugal including the the Mediterranean and in neighbourhood of Azores, Cape of Good Hope and coasts of Japan
Characteristic Features:
1. Body: elongated and shark-like.
2. Body Length: 1m long
3. Naked skin with characteristic of open groove loding the lateral line system.
4. Large head and compressed with a blunt snout.
5. Ventral mouth and nostrils
6. Large Pectoral and Pelvic fins
7. 2 dorsal fins, anterior over the pectoral fins with a stout spine in front and posterior one is continuous
8.Caudal fin consists of equal-sized dorsal and ventral lobes.
9. Tail: long, tapering and diphycercal
10. Head possesses a Frontal clasper armed with a pad of recurved dentricles in male
11.Behind the Pelvic fins a pair of claspers are present
7. Notopterus
Common name: Chital
Geographical distribution: Marshes and lakes of fresh water and brackish water of West Africa, India, Burma and Malaya .In fresh water of India N. chital is found
Importance: Food fish, its flesh is uncommonly rich and well flavoured
Food: carnivorous, feed on worms and insects
Characteristic Features:
1. Body: compressed strongly and covered with minute scales
2. Body Length: 1 m long
3. Body Colour: coppery brown or grayish with 15 or 16 silvery transverse bars
4. Small head and large mouth
5. Obtuse and convex snout
6. Small dorsal fin
7. Pelvic fin and Pectoral fins are very small
8. Anal fin elongated and confluent with the caudal fin
9. On the head musciferous channels are well-developed
10. Large air bladder with several divisions
8. Labeo
Common name: Rohu
Geographical distribution: all over Northern and central India found in Godavari and Krishna rivers
Importance: Food value
Characteristic Features:
1. Body: elongated with moderately rounded abdomen
2. Body Length: 1 m long
3. Body Colour: Brownish grey to black
4. Large scales and orange to reddish colour in centre
5. Blunt snout with prominent head
6. Semi-oval and transverse mouth
7. Thick lips covering the jaws,one on both having an inferior transverse folds
8. Soft and movable horny covering with a sharp margins on the inner side of the one or both lips
9. Barbles absent
10. Large air-bladder and divided into an anterior and posterior part
9. Catla
Common name: Katla
Geographical distribution: Throughout India ,scare to south of Krishna river
Importance: Rich in food value
Characteristic Features:
1. Body: elongated broad and stout
2. Body Length: 1 m long
3. Body Colour: Above blackish grey and silvery on sides
4. Scales are pink or coppery in centre on dorsal side and whitish below
5. Dorsal part of the body is more convex
6. Large head with large rounded eyes
7. Wide mouth with prominent lips
8. Large dorsal fin
9. Caudal fin is bilobed
10. Large air-bladder and divided into an anterior and posterior part
10. Heteropneustes
Common name: Singhi
Geographical distribution: Fresh water of India and Burma
 Heteropneustes fossilis Day
Charactersitic Features:
1. Body: elongated and laterally compressed
2. Body Length: 30 cm long
3. Scales absent on skin
4. Flattened head .eyes present with free circular margins
5. Barbles: long and 4 in pairs
6. Short dorsal fins without spine. At the level of the dorsal fin ventral fin is situated
7. Pectoral fin: strong with poison spine
8. Anal fin elongated, reaches upto the caudal fin separated from it by notch
9. Accessory breathing organs present
10. Air bladder present
11. Mystus
Geographical distribution: In India found in Jamuna, Ganga, Deccan rivers and Assam River
Habitat: Predatory. Attacks small carps, teleosts and prawns
Characteristic Features:
1. Body: elongated
2. Body Length: 1 m long
3. Long snout
4. Transverse and terminal mouth
5. Longer upper jaw
6. Barbles – 8
a) 2 nasal
b) 2 maxillary
c) 4 mandibular
7. Dorsal adipose fin well-developed
8. On the adipose fin circular black spot is present
9. Pectoral fin has strong spine
12. Exocoetus
Common name: Flying-fish
Geographical distribution: In tropical and warm parts of Atlantic and Indian oceans .E. pecilopterus is found in Indian Ocean to china seas
Importance: Good edible fish and provide fishery and certain seasons
Food: Feeds on prawns and young teleost and their eggs
Characteristic Features:
1. Body: moderately elongated ,compressed and covered with cycloid scales
2. Body Colour: bluish and silvery below .Pectoral fins have black spots
3. Wide mouth ,both jaws bear teeth
4. Enormously elongated pectoral fins to form wing-like structures so as to serve as parachute to sustain the fish in its glinding leaps
5. Short dorsal and anal fins
6. Hypobatic tail i.e. ventral lobe of the tail fin is large
7. Air-bladder present
13. Hippocampus
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_Saw_shark_-_William_Buelow_Gould,_c1832.jpg)
