POLYPTERUS BICHIR

Contents hide

1) POLYPTERUS BICHIR

1.1) CLASSIFICATION OF POLYPTERUS BICHIR

1.2) GEOGRAPHICAL DISTRIBUTION

1.3) HABIT AND HABITAT

1.4) GENERAL CHARACTERSTICS OF POLYPTERUS BICHIR

1.5) SPECIAL FEATURE

1.6) IDENTIFICATION

CLASSIFICATION OF POLYPTERUS BICHIR

Phylum :- CHORDATA (Notochord and dorsal tubular nerve cord present and gill-slits present).

Group :- CRANIATA (Cranium with brain present).

Subphylum :- VERTEBRATA (Vertebral column present).

Division :- GNATHOSTOMATA (Jaws and paired appendages present).

Super class :- PISCES (Paired fins , gills and skin with scales)

Class :- OSTEICHTHYES (Bony fishes).

SUB-CLASS :- PALAEOPTERGII (Ancient fishes. Dermal fin rays numerous. Clavicles present. Nostrils free from mouth cavity.)

Order :- CLADISTIA (Body slender, scales thick, rhomboid, enamelled. Air bladder lung like).

FAMILY :- POLYPTERIDAE (Pectoral fins lobate, while pelvic fms non-lobate)

GENUS :- Polypterus

SPECIES :- bichir

GEOGRAPHICAL DISTRIBUTION

Polypterus is restricted to tropical Africa, the Nile, Nigeria and Congo.

HABIT AND HABITAT

Polypterus is found in sea water. It becomes active during night. It feeds on small teleosts, batrachians and crustaceans.

GENERAL CHARACTERSTICS OF POLYPTERUS BICHIR

Polypterus is one of the most primitive living bony fish and could be easily regarded as living fossil. Body divisible into head, trunk and tail.
Body is elongated, cylindrical, measuring 1 metre in length and covered with rhombic ganoid scales.
Surface covering consists of a thin shiny enamel called ganoin.
Head is covered with a horny shield containing tubular nostrils and forwardly lying eyes.
Spiracles present.
There is a fleshy lip on the lower jaw matching that of the upper jaw.
Dorsal fin consists of a series of 5 to 18 isolated finlets composed of single spine-like scales to which are attaches! one or more soft rays.
Pectoral fins, found behind head, are broad rounded and lobed at bases. Ventral rm backwardly situated. Pelvic fins present. Caudal fin diphycercal.
Larva possesses plume-like external gills, attached to the hyoid arch, resembling the gills of Amphibian larva.

SPECIAL FEATURE

Polypterus shows combination of primitive and advanced characters. Primitive characters are non-overlapping scales, spiracle, certain skull bones and their arrangement, spiral valve in intestine and the superficial resemblance of paired fins to broad-based crossopterygian fins. It has also advanced features like dorso-lateral position of nostrils, pyloric caecum in the gut and similar urinogenital system, which bring them closer to bony fishes. The tail is no longer heterocercal. The air bladder though connected with pharynx seems to be respiratory organ but remains non-functional as Polypterus cannot live outside water for a longer period.

IDENTIFICATION

This fish has dorsal finlets and above features, hence it is Polypterus.

REFERENCES :-

https://en.wikipedia.org/wiki/Polypterus_bichir
https://depositphotos.com/stock-photos/polypterus-endlicheri.html
Book of Practical Zoology VERTEBRATE by S.S.LAL – Rastogi Publications.

OUR POSTS

CLARIUS : MAGUR
CLARIUS : MAGUR CLASSIFICATION OF CLARIUS : MAGUR Phylum :- CHORDATA ( Notochord and dorsal tubular nerve cord present and gill-slits present). Group :- CRANIATA ( Cranium with brain present ). [...READ MORE]
EXOCOETUS : FLYING FISH
EXOCOETUS : FLYING FISH CLASSIFICATION OF FLYING FISH : EXOCOETUS Phylum :- CHORDATA ( Notochord and dorsal tubular nerve cord present and gill-slits present). [...READ MORE]
MACACA MULATA : RHESUS MONKEY
MACACA MULATA : RHESUS MONKEY CLASSIFICATION OF MACACA MULATA : RHESUS MONKEY PHYLUM :- CHORDATA (Notochord, dorsal tubular nerve cord present and gill slits present ) Group :- CRANIATA ( Definite [...READ MORE]
OSTRACION : TRUNK FISH
OSTRACION : TRUNK FISH CLASSIFICATION OF OSTRACION : TRUNK FISH Phylum :- CHORDATA ( Notochord and dorsal tubular nerve cord present and gill-slits present). Group :- CRANIATA ( Cranium with brain [...READ MORE]
AMIA CALVA (BOWFIN)
Amia calva(Bowfin) CLASSIFICATION OF AMIA CALVA (BOWFIN) Phylum :- CHORDATA (Notochord and dorsal tubular nerve cord present and gill-slits present). Group :- CRANIATA (Cranium with brain present). [...READ MORE]
ALLIGATOR
ALLIGATOR CLASSIFICATION OF ALLIGATOR PHYLUM :- CHORDATA (Notochord, dorsal tubular nerve cord present and gill slits present ) Group :- CRANIATA ( Definite head. Cranium with brain present ) [...READ MORE]
AMMOCOETE LARVA
CYCLOSTOMATA SLIDES Lamprey : Ammocoete : Larva Whole Mount COMMENTS :- It is one of the stages in the development of lamprey. Egg develops into ammocoete larva, which is a tiny transparent creature [...READ MORE]
Ancistrodon : Pit Viper
Ancistrodon : Pit Viper CLASSIFICATION OF ANCISTRODON : PIT VIPER PHYLUM :- CHORDATA (Notochord, dorsal tubular nerve cord present and gill slits present ) Group :- CRANIATA ( Definite head. Cranium [...READ MORE]
BIRD SLIDES
BIRD SLIDES – PIGEON V.S. of Skin Comments: v.s. skin of pigeon shows main two layers: Epidermis, Dermis. Epidermis contains the following layers : (i) Outermost layer is called as epitrichium [...READ MORE]
Comparative Account of Brain in Vertebrate
Comparative Account of Brain in Vertebrate Brain of all vertebrates, from fish to man, is built in accordance with the same basic architectural plan. However, form of brain differs in different [...READ MORE]