This document provides an overview of the many ways that fish diversity can be categorized, including by species, habitat, lifespan, size, breeding behavior, brooding behavior, feeding behavior, vision, shape, locomotion, toxicity, and human use. It discusses the large number of fish species that have been discovered and some of the extreme variations that can be seen between different types of fish in each of these categories.
4. Contents
Diveristy in Fishes
•By species
Jawless fish
Cartilaginous fish
Bony fish
Teleosts
•By habitat
•By life span
•By size
•By breeding behavior
•By brooding behavior
•By feeding behaviour
•By vision
•By shape
•By locomotion
•By toxicity
•By human use
•References
5. FISH:-
Fish are very diverse animals and can be categorised in many ways. This article is an overview of some of
ways in which fish are categorised. Although most fish species have probably been discovered and described,
about 250 new ones are still discovered every year. According to FishBase, 33,100 species of fish had been
described by April 2015. That is more than the combined total of all
other vertebrate species: mammals,amphibians, reptiles and birds.
Fish species diversity is roughly divided equally between marine (oceanic) and freshwater ecosystems. Coral
reefs in the Indo-Pacific constitute the centre of diversity for marine fishes, whereas continental freshwater
fishes are most diverse in large river basins of tropical rainforests, especially the Amazon, Congo,
and Mekongbasins. More than 5,600 fish species inhabit Neotropical freshwaters alone, such that Neotropical
fishesrepresent about 10% of all vertebrate species on the Earth. Exceptionally rich sites in the Amazon basin,
such as Cantão State Park, can contain more freshwater fish species than occur in all of Europe.
BY SPECIES FISH:-
JAWLESS FISH
Jawless fish were the earliest fish to evolve. There is current debate over whether these are really fish at all.
They have no jaw, no scales, no paired fins, and no bony skeleton. Jawless fish inhabit both fresh and salt water
environments. Some are anadromous, moving between both fresh and salt water habitats.Extant jawless fish are
either lamprey or hagfish. It is the only invertebrate fish and the only animal which has a skull but no vertebral
column. It has four hearts, two brains, and apaddle-like tail.
Lampreys attached to a lake trout
8. Cartilaginous fish:-
Cartilaginous fish have a cartilaginous skeleton. However,
their ancestors were bony animals, and were the first fish to
develop paired fins. Cartilaginous fish don't have swim
bladders. Their skin is covered in placoid scales (dermal
denticles) that are as rough as sandpaper. Because
cartilaginous fish do not have bonemarrow, the spleen and
special tissue around the gonads produces red blood cells.
There are over 980 species of cartilaginous fish. They
include sharks, rays and chimaera.
Tiger shark
10. This elephant fish is achimaera
Bony fish:-
Bony fish include the lobe-finned fish and the ray finned fish. The lobe-finned fish is the class of fleshy
finned fishes, consisting of lungfish, and coelacanths. They are bony fish with fleshy, lobed paired fins,
which are joined to the body by a single bone. These fins evolved into the legs of the
first tetrapod land vertebrates,amphibians. Ray finned fishes are so-called because they
possess lepidotrichia or "fin rays", their fins being webs of skin supported by bony or horny spines
("rays").
fishes: the chondrosteans, holosteans, and teleosts. The chondrosteans and holosteans are among the
earlier fish to evolve, and share characteristics with both teleosts and sharks. In comparison with the
other chondrosteans, the holosteans are closer to the teleosts and further from sharks.
Lungfish can brThere are three types of ray finned eathe in air as well as water
11. Model of a coelacanth, thought until 1938 to be extinct. They are deep blue.
13. Teleosts:-
Teleosts are the most advanced or "modern" fishes. They are
overwhelmingly the dominant class of fishes (or for that
matter, vertebrates) with nearly 30,000 species, covering about
96 percent of all extant fish species.
.
Swordfish are teleosts
16. Abyssobrotula
The world's deepest living
fish, Abyssobrotula galatheae, a species
of cusk eel, lives in the Puerto Rico
Trenchat a depth of 8,372 meters
(27,467 ft). Due to the extreme pressure,
this appears to be around the theoretical
maximum depth possible for fish.
galatheae
By habitat:-
Fish are found in nearly all natural aquatic environments. Most fish, whether by species
count or abundance, live in warmer environments with relatively stable
temperatures. However, some species survive temperatures up to 44.6 °C (112.3 °F), while
others cope with colder waters; there are over 200 finfish species south of the Antarctic
Convergence. Some fish species tolerate salinities over 10 percent.
17. Stone loach
At the other
extreme, the
Tibetan stone
loach lives at
altitudes over
5,200 meters
(17,100 ft) in the
Himalayas.
Blue shark
Some
marine pelagic
fish range over
vast areas, such as
the blue shark that
lives in all oceans.
18. Blind cave fish
Other fish are confined to
single, small living
spaces, such as the blind
cave fish in North
America.
Death Valley
pupfish
Equally isolated
desert pupfish, like
the Death Valley
pupfish (pictured), live in
small desert spring
systems in Mexico and the
southwest United States.
Thermichthys
hollisi
The bythitid vent
fish Thermichthys hollisi,
lives around thermal
vents 2,400 metres (1,300
fathoms) deep.
19. Sargassum frogfish
The highly
camouflaged sargassum
frogfish lives in
drifting sargassum
seaweed. It has adapted
fins which can grab strands
of sargassum, enabling it
to climb through the
seaweed. It avoids threats
from larger predator fish
by climbing out of water
onto the surface of a
seaweed mat, where it can
survive for some time.
20. Seven-figure
pygmy goby
Among gobies, small coral
reef-dwelling
fish (pictured), are some of
the shortest lived fishes.
The seven-figure pygmy
goby is the shortest lived of
all fish species. It lives at
most for 59 days, which is
the shortest lifespan for
By life span:-
Some of the shortest-lived species are gobies, which are small coral reef–dwelling fish.
Some of the longest-lived are rockfish.
21. Ram
cichlid
Short lived fish have particular
value in genetic studies on aging.
In particular, the ram cichlid is
used in laboratory studies because
of its ease of breeding and
predictable aging pattern.
22. Rougheye
rockfish
Some of the longest living fishes
are rockfish. The longest lived fish is
the 205 years reported for
the rougheye rockfish, Sebastes
aleutianus (pictured). This fish is
found offshore in the North Pacific at
25–900 metres (14–492 fathoms)
and exhibits negligible senescence.
24. Koi
There are stories about
Japanese koi goldfish passed from
generation to generation for
300 years. Counting growth lines on
the scales of fish confined to ponds
or bowls is unreliable, since they lay
down extra lines. The maximum
reliably reported age for a goldfish is
41 years
25. Paedocypris
progenetica
Paedocypris progenetica, a type
of minnow, is the smallest of all fish
species. It lives in the dark-
colored peat swamps of the
Indonesian island of Sumatra. The
females of this species have
a standard length of 7.9 mm
(0.31 in) at maturity. Until recently,
this was the smallest of all known
vertebrates. However, recently a
minute Papua New Guinea
frog, Paedophryne amauensis, with
a standard length of 7.7 mm
By size:-
26. Photocorynu
s spiniceps
Male individuals of
the anglerfish species Photocorynus
spiniceps are 6.2-7.3 mm long at
maturity, and thus could be claimed
as an even smaller species. However,
these males do not survive on their
own merits but only by sexual
parasitism on the larger female.
27. Stout
infantfish
The stout infantfish, a type
of goby, is the second smallest
known fish. Females grow to a
length of 8.4 millimetres (0.33 in)
and males are mature at 7
millimetres (0.28 in).
28. Whale shark
The largest fish is the whale shark. It
is a slow moving filter
feeding shark with a maximum
published length of 20 m (66 ft) and a
maximum weight of 34 tonnes. Whale
sharks can live up to 70 years. The
whale shark is a vulnerable fish.
29. By breeding behavior:-
In very deep waters, it is not easy for a fish to find a mate.
There is no light, so some species depend
on bioluminescence. Others are hermaphrodites, which
doubles their chances of producing both eggs and sperm
when an encounter does occur
31. Anglerfish
Female Haplophryne mollis anglerfish
trailing atrophied males she
encountered. The
female anglerfishreleases pheromones t
o attract tiny males. When a male finds
her, he bites on to her and never lets go.
When a male of the anglerfish
species Haplophryne mollis bites into
the skin of a female, he release
anenzyme that digests the skin of his
mouth and her body, fusing the pair to
the point where the two circulatory
systems join up. The male
then atrophies into nothing more than a
pair of gonads. This extreme sexual
dimorphism ensures that, when the
female is ready to spawn, she has a
mate immediately available.
32. Hammerheads
Some sharks, such
as hammerheads are able
to breed parthogenetically,
that is asexually where the
growth and development
of embryos occur
without fertilization.
33. Fish adopt a variety of strategies for nurturing their brood. Sharks, for example, variously follow
three protocols with their brood. Most sharks, including lamniformes are ovoviviparous, bearing
their young after they nourish themselves after hatching and before birth, by consuming the
remnants of the yolk and other available nutrients. Some such as hammerheads are viviparous,
bearing their young after nourishing hatchlings internally, analogously to mammalian gestation.
Finally catsharks and others are, oviparous, laying their eggs to hatch in the water.
Some animals, predominantly fish such as cardinalfish practice mouthbrooding, caring for their
offspring by holding them in the mouth of a parent for extended periods of time. Mouthbrooding
has evolved independently in several different families of fish.
By brooding behavior:-
34. Chain cat shark
The chain
catshark is oviparou
s, laying its eggs to
hatch in the water.
Great white shark
The great white
shark is ovoviviparo
us, gestating eggs in
the uterus for
11 months before
giving birth.
35. Scalloped hammerhead
The scalloped
hammerhead is viviparous,
bearing its young after
nourishing hatchlings
internally
Cyphotilapia frontosa
A female Cyphotilapia
frontosa mouthbrooding fry
which can be seen looking
out her mouth
38. Anglerfish
Anglerfish are lie-in-
wait ambush predators. The
first spine of their dorsal
fin has been modified so it can
be used like a fishing line with
a lure at the end. Most
anglerfish, like the one
pictured, live in the darkness
of thedeep sea and have
a bioluminescent lure.
39. Archerfish
Archerfish prey on land
based insects and other small
animals by literally shooting
them down with water
droplets from their
specialized mouths.
40. Trigger fish
Trigger fish also use jets of water, to
uncover sand dollars buried in sand or
overturn sea urchins.
41. Silver
arowana
Other fish have developed
extreme specializations. Silver
arowana, also called monkey
fish, can leap two meters out of
the water to capture prey.
42. Cookiecutter
shark
The cookiecutter shark is a
small dogfish which derives its name
from the way it removes small circular
plugs, looking as though cut with a
cookie cutter, from the flesh and skin
of cetaceans and larger fish, including
other sharks.
43. Striped bass Striped bass eat smaller fish
Chinese
algae eater
Chinese algae eaters are kept
in aquaria to control algae.
Emperor
angelfish The Emperor angelfish feeds
on coral sponges
Herring
Schooling herrings ram
44. The mangrove jack eats crustaceans
Many puffer fish species crush the shells of molluscs
The bucktoothed tetra eats scales off other fishes
(lepidophagy)
45. Cleaner fish
These two small wrasses are cleaner fish,
and eat parasites off other fish.
Cleaning
station
A reef manta ray at a cleaning station,
maintaining a near stationary position atop a
coral patch for several minutes while being
cleaned by cleaner fishes
Doctor fish
Doctor fish nibbling on the diseased skin of
patients. Doctor fish (nibble fish) live and
breed in the outdoor pools of
some Turkish spas, where they feed on the
skin of patients with psoriasis. The fish are
like cleaner fish in that they only consume
the affected and dead areas of the skin,
leaving the healthy skin to recover.
46. Many species of fish can see the ultraviolet end of
the spectrum, beyond the violet.Mesopelagic
fishes live in deeper waters, in the twilight zone
down to depths of 1000 metres, where the amount
of sunlight available is not sufficient to
supportphotosynthesis. These fish are adapted for
an active life under low light conditions.
By vision:-
47. Four-eyed
fish
The four-eyed fish feeds at the surface of
the water with eyes that allow it to see
both above and below the surface at the
same time. Four-eyed fish actually have
only two eyes, but their eyes are specially
adapted for their surface-dwelling
lifestyle. The eyes are positioned on the
top of the head, and the fish floats at the
water surface with only the lower half of
each eye underwater. The two halves are
divided by a band of tissue and the eye
has two pupils, connected by part of
the iris.
Two stripe
damselfish
The two stripe damselfish can signal
secret alarms by reflecting ultraviolet to
other fish of its species. The two stripe
damselfish, Dascyllus reticulatus, has
ultraviolet-reflecting colouration which
they appear to use as an alarm signal to
other fish of their species.
48. Barreleye
The barreleye has barrel-
shaped, telescopic eyes
which are generally directed
upwards, but can also be
swivelled
forward. Barreleyes are a
family of small, unusual-
looking mesopelagic fishes,
named for their barrel-
shaped, tubular eyes which
are generally directed
upwards to detect the
silhouettes of available prey.
49. By shape:-
Box fishes have heavily armoured plate
-like scales fused into a solid, triangular,
boxlike carapace, from which the fins,tail, eyes
and mouth protrude.
Because of this heavy armour,
boxfish move slowly, but few other fish are
able to eat the adults.
50. The humpback turret fish
is a boxfish with an
armoured triangular
shaped body
52. Dwarf
seahorse
The slowest-moving fishes
are the sea horses. The
slowest of these, the
tiny dwarf seahorse, attains
about five feet per hour.
Atlantic
bluefin
tuna
The Atlantic bluefin tuna is
capable of sustained high
speed cruising, and
maintains high muscle
temperatures so it can
cruise in relatively cold
waters.
53. Indo-Pacific
sailfish
Among the fasted sprinters are
the Indo-Pacific sailfish (left) and
the black marlin (right). Both have
been recorded in a burst at over 110
kilometres per hour (68 mph). For
the sailfish, that is equivalent to 12
to 15 times their own length per
second.
Shortfin
mako
The shortfin mako's speed has been
recorded at 50 kilometres per hour
(31 mph), and there are reports that it
can achieve bursts of up to 74
kilometres per hour (46 mph). It can
jump up to 9 meters (30 ft) in the air.
Wahoo
The wahoo is perhaps the fastest fish
for its size, attaining a speed of
19 lengths per second, reaching 78
kilometres per hour (48 mph).
54. Flying fish
Flying fish have unusually
large pectoral fins, Their glides are
typically around 50 meters (160 ft),
but they can use updrafts at the
leading edge of waves to cover
distances of at least 400 meters
(1,300 ft). In May 2008, a flying fish
was filmed off the coast of Japan
Climbing
perches
Climbing perches are a family of
fishes which have the ability to climb
out of water and "walk" short
distances.
Mudskipper
The mudskipper is another type of
walking fish. Walking fish are
often amphibious and can travel
over land for extended periods of time.
55. Toxic fish produce strong poisons in their bodies. Both poisonous
fish and venomous fish, contain toxins, but deliver them differently.A 2006
study found that there are at least 1200 species of venomous fish. There are
more venomous fish than venomous snakes. In fact, there are more venomous
fish than the combined total of all other venomous vertebrates. Venomous fish
are found in almost all habitats around the world, but mostly in tropical
waters. They wound over 50,000 people every year.
They carry their venom in venom glands and use various delivery systems,
such as spines or sharp fins, barbs, spikes and fangs. Venomous fish tend to
be either very visible, using flamboyant colors to warn enemies, or skilfully
camouflaged and maybe buried in the sand. Treatment for venom stings
usually includes the application of heat, using water at temperatures of
about 45 °C (113 °F), since heat breaks down most complex venom proteins.
By toxicity:-
56. Puffer fish
The puffer fish is
the most
poisonous fish in
the world. It is the
second most
poisonous
vertebrate after
the golden dart
frog. It paralyzes
the diaphragm
muscles of human
victims, who can
die from
suffocation. In
Japan, skilled
chefs use parts of
a closely related
species,
57. Spotted trunkfish
The spotted trunkfish secretes
a ciguatera toxin from glands on
its skin. The spotted trunkfish is
a reef fish which secretes a
colourless ciguatera toxin when
touched. The toxin is only
dangerous when ingested, so
there's no immediate harm to
divers.
Giant moray
The giant moray is a reef fish at
the top of the food chain. Like
many other apex reef fish, it is
likely to
causeciguatera poisoning if
eaten. Outbreaks of ciguatera
poisoning in the 11th to 15th
centuries from large, carnivorous
reef fish, caused by harmful
algal blooms, could be a reason
why Polynesians migrated
to Easter Island, New Zealand,
and possibly Hawaii.
58. Reef stonefish
The most venomous known fish is
the reef stonefish. It has a remarkable
ability to camouflage itself amongst
rocks. It is an ambush predator that sits
on the bottom waiting for prey to
approach. Instead of swimming away
if disturbed, it erects 13 venomous
spines along its back. For defense, it
can shoot venom from each or all of
these spines.
Lionfish
Head on view of the beautiful lionfish,
a venomous coral reef fish Unlike
stonefish, a lionfish can release venom
only if something strikes its spines.
Although not native to the U.S. coast,
lionfish have appeared
around Florida and have spread up the
coast to New York
59. Yellowfin tuna
Yellowfin tuna are
now being fished
as a replacement
for the
depleted southern
bluefin tuna.
Anchovy
These schooling an
chovy are forage
fish
Atlantic cod
Atlantic
cod fisheries have
collapsed
By human use:-
61. Bony-eared ass fish
Fish hold the records
for the relative brain
weights of
vertebrates. Most
vertebrate species
have similar brain-to-
body weight ratios.
The deep sea
bathypelagic bony-
eared ass fish, has the
smallest ratio of all
known vertebrates.
Elephantnose fish
At the other extreme,
the elephantnose fish,
an African freshwater
fish, has an
exceptionally large
brain-to-body weight
ratio.
62. Hallucinogenic fish
These widely distributed coastal fish
became a recreational drug during
the Roman Empire, and are called "the
fish that make dreams" inArabic.
Other hallucinogenic fish are Siganus
spinus, called "the fish that inebriates"
in Reunion Island, and Mulloidichthys
samoensis, called "the chief of ghosts"
in Hawaii.
63. Vampire fish
Smaller species of vampire
fish, native to the Amazon
River, have an alleged tendency
to burrow into and parasitise
the human urethra. However,
despite ethnological reports
dating back to the late 19th
century, the first documented
case of the removal of a
vampire fish from a human
urethra did not occur until
1997, and even that incident
has remained a matter of
controversy.