Polypterid 2.0, The Primer Options

[Anne]

Introduction
Polypterids are the sole survivors of the Order Polypteriformes whose distribution included S.America and Africa and can be dated back at least 100 million years in the fossil record. They are among the most primitive of the ray-finned fishes (Actinopterygii) the dominant group of fishes today.

The elongate body of a Polypterid range from 10 inches to 3 ft long depending on the species and round in cross section becoming compressed near the tail.They have a powerful body

Polypterids are covered by multilayered scales,rhomboid in shape and have articulating peg and socket joints between them,With an outer layer of ganoine( (an inorganic bone salt) a middle layer of dentine a layer of isopidine and an inner dermal, cosmine bony layer and are referred to as ganoid scales. Only the bowfin (Amiidae) share this particular ganoid scale construction.

The dorsal fin of the Polypterids is split into a row of small, sail-like finlets that are erected individually when the animal is agitated or feels threatened.

Newly hatched Polypterids have feathery gills, not unlike lungfishes, which may be retained for some time.Most individuals lose them by the time
they have reached 2-3 inches.Polypterids are suited to life in warm stagnant backwaters and swamps where oxygen levels are low. They have adapted to these habitats by the use of a primitive form of lungs which allow them to breathe atmospheric air as opposed to being dependent on dissolved oxygen.

The Polypterids are shallow water species often swimming in the weeds and plants near shores and banks of Central African lakes and rivers. They seem to vary between diurnal and nocturnal depending on species in the wild

They are sometimes caught as a food fish and are said to be quite tasty.

In addition to the ten species and six subspecies of Polypterus, the family also includes the ropefish, Erpetoichthys calabaricus, similar in character and distribution but lacking the pelvic fins and with a longer eel-like form.

All species of Polypterus require the same care just the size of the tank changes bigger species bigger tanks.

Polypterids tend to be long lived averaging 10-15 years in captivity.

charts and maps from Fish and Fisheries 2001,2,113-124

This post has been edited by Anne: Oct 10 2005, 06:03 AM

Attached File(s)

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[Anne]

Polypterids are classified as follows
Taxonomic hierarchy
Kingdom Animalia -- Animal
Phylum Chordata -- chordates
Subphylum Vertebrata -- , vertebrates
Superclass Osteichthyes -- bony fishes
Class Actinopterygii -- ray-finned fishes, spiny rayed fishes
Subclass Chondrostei -- paddlefishes, sturgeons
Order Polypteriformes
Family Polypteridae -- bichirs,lobed-finned pike, reed fishes
Genus Polypterus
Species(example) Polypterus senegalus senegalus - gray bichir-Cuviers bichir

dates listed are when the species were described
Cladistia Cope, 1871 after Lund, 2000<==o CLADISTIA Cope, 1871 sensu Lund, 2000
|--o †GUILDAYICHTHYIFORMES Lund, 2000
| `--o †Guildayichthyidae Lund, 2000
| |-- †Guildayichthys carnegiei Lund, 2000
| `-- †Discoserra pectinodon Lund, 2000
`--o POLYPTERIFORMES [Brachiopterygii] (niilinhaukikalat)
|?- †Dagetella sudamericana [Dajetella]
`--o Polypteridae (niilinhauet; bichirs)
|-- Calamoichthys calabaricus (Smith, 1865) [Erpetoichthys] (käärmehauki, käärmekala; Reedfish)
`--o Polypterus (niilinhauet; bichirs) [9?]
|-- P. ansorgii Boulenger, 1910 (Guinean bichir)
|--o P. bichir Geoffroy St. Hilaire, 1802 (niilinhauki)
| |-- P. b. bichir Geoffroy St. Hilaire, 1802 (Nile bichir)
| |-- P. b. katangae Poll, 1941
| `-- P. b. lapradei Steindachner, 1869
|-- P. delhezi Boulenger, 1899 (Barred bichir)
|--o P. endlicheri Heckel, 1846-49
| |-- P. endlicheri congicus Boulenger, 1898
| `-- P. endlicheri endlicheri Heckel, 1846-49 (Saddled bichir)
|-- P. ornatipinnis Boulenger, 1902 (Ornate bichir)
|--o P. palmas Ayres, 1850 (Shortfin bichir)
| |-- P. palmas buettikoferi Steindachner, 1891
| |-- P. palmas palmas Ayres, 1850 (Shortfin bichir)
| `-- P. palmas polli Gosse, 1988
|-- P. retropinnis Vaillant, 1899 (West African bichir)
|--o P. senegalus Cuvier, 1829 (Gray bichir)
| |-- P. senegalus meridionalis Poll, 1941
| `-- P. senegalus senegalus Cuvier, 1829 (Gray bichir)
`-- P. weeksii Boulenger, 1898 (Mottled bichir)

Reference(s):
Carroll, R. L., 1988: Vertebrate paleontology and evolution.
--W. H. Freeman and company, New York, 1988. 698.
Carroll, R. L., 1988: Appendix. 594-648.
in Carroll, R. L., 1988: Vertebrate paleontology and evolution.
--W. H. Freeman and company, New York. 1988.
Frickhinger, K. A., 1995: Fossil Atlas - Fishes. 1-1088
--Mergus, Publishers for Natural History and Pet Books, Hans A.Baensch, Malle, Germany
Froese, R. & Pauly, D. (eds), 2001: FishBase.
--iNet: www.fishbase.org
Long, J. A., 1995: The Rise of Fishes: 500 million years of evolution.
--Johns Hopkins University Press, Baltimore & London, pp. 1-223
Lund, R., 2000: The new actinopterygian order Guildayichthyiformes from the
Lower Carboniferous of Montana (USA).
--Geodiversitas: Vol. 22, #2, pp. 171-206
Nelson, J. S., 1994: Fishes of the world.
--John Wiley & Sons, Inc., New York, 1994. XX-600.

This post has been edited by Anne: Sep 6 2005, 11:16 AM

[Anne]

Species and sizes
maximum known sizes often smaller in captivity
Upper Jaw Species-Upper jaw protrudes past lower jaw
P. palmas palmas ('palmas' bichir)- 13"
(subspecies)P. palmas polli ('marbled bichir)- 14"(there seems to be enough evidence to promote this to its own species)
(subspecies) P. palmas buettikoferi ('buettikoferi' bichir)- 13"
P. ornatipinnis ('ornate' bichir)- 27"
P. delhezi ('armoured' or 'delhez's' bichir)- 14"
P. senegalus senegalus ('Senegal' or 'Cuiver's' bichir)- 12"
(subspecies)P. senegalus meridionalis- 12"
P. retropinnis retropinnis ('retropinnis' bichir)- 14"
(subspecies)P. retropinnis lowei ('Lowe's' bichir)- 12"
P. weeksi ('week's' bichir)- 20"
P.teugelsi(new species not described yet)
E. calabaricus ('Ropefish')- 15"-30"

Lower Jaw Species-Lower protrudes past upper jaw
P. endlicheri endlicheri ('saddled' or 'red' bichir)- 32", possibly more
(subspecies)P. endlicheri congicus ('giant' or 'congo' bichir)- 39"
P. lapradei ('Lapradei' bichir)- 24"
P. bichir bichir-30+ ''
P.ansorgii*

Variations
There are variations of the above including
short bodied
longfinned
albinoism
leustic
albino Polypterids have a pink/ white body with red eyes if they are a species with pronounced markings
these are often yellowish in color.
Leustic (platinum) are silver/whitish bodies with black eyes.

*There are only 3 known examples to exist and they are in museums its possible
this species is extinct.

This post has been edited by Anne: Sep 4 2005, 09:24 PM

Attached File(s)

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[Anne]

In the wild they are found in the following countries
Burkina Faso
Polypterus bichir lapradei
Polypterus endlicheri endlicheri
Polypterus senegalus senegalus
Benin--------------------------------------------
Polypterus bichir lapradei
Polypterus endlicheri endlicheri
Polypterus retropinnis
Polypterus senegalus senegalus
Cameroon-------------------------------------
Polypterus bichir bichir
Polypterus bichir lapradei
Polypterus endlicheri endlicheri
Polypterus ornatipinnis
Polypterus palmas polli
Polypterus retropinnis
Chad---------------------------------------------
Polypterus bichir bichir
Polypterus bichir lapradei
Polypterus endlicheri endlicheri
Polypterus senegalus senegalus
Central African Republic
Polypterus endlicheri endlicheri
Polypterus retropinnis
Congo------------------------------------------
Polypterus bichir
Polypterus delhezi
Polypterus endlicheri congicus
Polypterus ornatipinnis
Polypterus palmas palmas
Polypterus palmas polli
Polypterus retropinnis
Polypterus senegalus meridionalis
Polypterus weeksii
Egypt---------------------------------------------
Polypterus bichir bichir
Polypterus senegalus senegalus
Etheopia----------------------------------------
Polypterus bichir bichir
Polypterus senegalus senegalus
Equitoral Guinea----------------------------
Erpetoichthys calabaricus
Guinea------------------------------------------
Polypterus ansorgii *(see note)
Polypterus palmas buettikoferi
Polypterus palmas palmas
Polypterus senegalus senegalus
Guinea-Basso--------------------------------
Polypterus ansorgii Guinean bichir *(see note)
Polypterus bichir bichir Nile bichir
Polypterus bichir lapradei Bichir
Polypterus endlicheri endlicheri
Polypterus palmas palmas
Polypterus senegalus senegalus
Gabon------------------------------------------
Polypterus retropinnis
Ghana------------------------------------------
Polypterus bichir bichir Nile bichir
Polypterus endlicheri endlicheri
Polypterus palmas palmas
Polypterus retropinnis
Polypterus senegalus senegalus
Ivory Coast------------------------------------
Polypterus bichir bichir Nile bichir
Polypterus endlicheri endlicheri
Polypterus palmas palmas
Polypterus retropinnis
Kenya-------------------------------------------
Polypterus bichir bichir Nile bichir
Polypterus senegalus senegalus Gray bichir
Liberia------------------------------------------
Polypterus palmas buettikoferi
Polypterus palmas palmas
Polypterus retropinnis
Mali----------------------------------------------
Polypterus bichir lapradei
Polypterus endlicheri endlicheri
Niger---------------------------------------------
Polypterus bichir lapradei
Polypterus senegalus senegalus
Nigeria------------------------------------------
Polypterus bichir bichir
Polypterus bichir lapradei
Polypterus endlicheri endlicheri
Polypterus retropinnis
Republic of Congo-------------------------
Polypterus bichir katangae
Polypterus delhezi
Polypterus endlicheri congicus
Polypterus ornatipinnis
Polypterus palmas polli
Polypterus retropinnis
Polypterus weeksii
Senegal----------------------------------------
Polypterus bichir lapradei
Polypterus palmas buettikoferi
Polypterus senegalus senegalus
Sierra Leon------------------------------------
Polypterus palmas buettikoferi
Polypterus palmas palmas
Polypterus senegalus senegalus
Sudan-------------------------------------------
Polypterus bichir bichir
Polypterus endlicheri endlicheri
Polypterus senegalus senegalus
Tanzania---------------------------------------
Polypterus endlicheri congicus
Polypterus ornatipinnis
Polypterus senegalus senegalus
Togo--------------------------------------------
Polypterus retropinnis
Polypterus senegalus senegalus
Uganda----------------------------------------
Polypterus senegalus senegalus
Zambia-----------------------------------------
Polypterus endlicheri congicus
Polypterus senegalus senegalus

[Anne]

WHY BICHIR?

When Europeans (French) discovered the genus Polypterus in 1809 it had already been known along the Nile since the time of the pharoahs. The local peoples referred to them as bichirs (unknown pronunciation and spelling). While unable to come up with an exact meaning for the word it was most likely a descriptive term (''whip'' has been suggested) for this type of fish.

The French most likely pronounced it as phonetically as possible to the orginal native word and came up with bee-sheer as a pronunciation and spelled 'bichir'. Since this would be the name of these fish for
several years until they were scientifically described and put into the proper family it became an accepted common name.

However the correct English pronunciation is up for grabs. Several dictionaries all have their own pronunciation including the below:
bee cher
beech er
biker
bitcher
bi cher
Also known by the common name lobed fin pike,dinosaur eel.
The name Polypterus : poly=many + pterus=fins and is pronounced po-lyp'-terus.

[Anne]

Polypterid
SCALES
Polypterids are covered by multilayered scales, rhombiod in shape, with an outer layer of ganoine a middle layer of dentine a layer of isopidine and an inner dermal, cosmine bony layer and are referred to as ganoid scales. Only the bowfin (Amiidae) share this scalation. While the scales of Lepisosteidae species may look the same they lack the middle dentine layer present in Polypterids and Amiidae.

[Anne]

SLIMECOAT
Is a mucous created by the continal replacement of glandular cells know in the fishes skin that produce a glycoprotein which is called mucin. This when mixed with water forms the mucus that makes up the slime coat of fish.Fish with poorly developed scales tend to produce more of this slime coat.. The slime coat does threee basci things- it reduces turbulence for the fish when swimming by smotthing over the areas between the fishes scales-it helps regulate the internal/external ionic balance and the efficiecy of gases exchanged through the skins surface-ie-osmoregullation and it provides a slipery surface that in it's sloughing off prevents bacteria from attching themselves to the skin. Bacteria is simply washed away from the skin with this process. It also aids in acting as a wound bandage.Stressed fish have a change in their slime coat-either too much or too little.One sign of a stressed bichir is usually overproduction of its slimecoat

[Anne]

FINS
The fins on fish serve many purposes on polypterids starting at the front.
The lobed pectoral fins are used for braking and manuvering,and casual swiming
The dorsal finlets are raised and lowered in threat assesment and for defense ,
The pelvic fins are used as stabilizers.
The anal fin serves a two fold purpose,one is stabilization the other during mating
The cadual fin and the rear of the body as their main propulsion when speed or power is required.

This post has been edited by Anne: Aug 18 2005, 10:08 PM

Attached File(s)

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[Anne]

LATERAL LINE
The lateral line system consists of bendable nerve endings in a series of mucous-filled canals Vibrations in the water or differential pressure in different parts of the canal cause the fluid to move and distort the nerve endings.
Because of it's name, we think of the lateral-line system as being oriented laterally on
the fish.Closer inspection shows a concentration of sensory receptors on the head
branching into 4 lines.The occipital,The supraorbital, The suborbital and The
hyomandibular.
The lateral line system enables detection of both vibrations in the water and changes in the pressure field set up as the fish swims. It provides information to the fish about movements of nearby organisms, very-low-frequency sound, differential current velocity, and back pressure built up as the fish approaches an obstacle.The lateral line sense is sufficiently directional to enable blinded fish to find and capture prey.

A swimming fish sets up a pressure wave in the water that is detectable by the lateral line systems of other fishes. It also sets up a bow wave in front of itself, the pressure of which is higher than that of the wave flow along its sides. These near-field differences are registered by its own lateral line system. As the fish approaches an object, such as a rock or the glass wall of an aquarium, the pressure waves around its body are distorted, and these changes are quickly detected by the lateral line system, enabling the fish to swerve or to take other suitable action. Because sound waves are waves of pressure, the lateral line system is also able to detect very low-frequency sounds of 100 Hz or less.

Attached File(s)

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[Anne]

EYESIGHT
To be filled in later