Infraclass Teleostei: “Teleosts”
 The
vast majority of modern fishes are
“teleosts.”
 They
have replaced the heavy, armored
scales of their ancestors with much lighter
more flexible scales that overlap each
other and also have evolved homocercal
symmetrical tails.
Class
Actinopterygii
Subclass
Chondrostei
[37 species]
Subclass
Neopterygii
Order Acipenseriformes
(paddlefish and sturgeons)
Order Polypteriformes
(bichirs)
Infraclass
Holostei
[8 species]
Order
Lepisosteiformes
(gars)
Order
Amiiformes
(bowfin)
Infraclass
Teleostei
12 superorders
Figure 24.15
Figure 24.18
Teleosts

The teleosts are extremely abundant and have
diversified into an enormous number of species
(depending on authority about 24,000 species).

They represent about half of all vertebrate
species and have colonized all marine and
freshwater habitats from -11,000 m to +4,500m
and occupy water that ranges in temperature
from polar (-1.8ºC) to hot springs (43ºC).
Teleost characters
 Homocercal
tail
 Circular scales without ganoine
 Ossified vertebrae
 Swim bladder – structure and function
discussed previously.
 Skull with complex jaw mobility
Jaw mobility in teleosts
 The
skull in teleosts has become greatly
lightened from the much more robustly
constructed skull of the holosteans and is
much more flexible.
 Bones
in the upper jaw, which were once
firmly fixed to the skull and had teeth have
become more loosely attached and teeth
are often absent.
http://people.biology.ufl.edu/sahilber/VertZooLab2007/Vert%20Zoo%20Images/Lab%202
/Bowfin_skull_1.jpg
Jaw mobility in teleosts
 The
maxillary bone (on the upper jaw) is
mobile in teleosts [and in bowfins, but not
gars].
 In addition the premaxillary bone (which is
anterior to the maxilla) is also mobile.
Jaw mobility in teleosts

This mobility in the upper jaws has contributed
to a major development in the teleosts, which is
the conversion of jaws from simple devices for
grasping to sophisticated suction devices.

An approaching fish can push prey away just as
your hand does when you reach for something
underwater, but a rapid expansion of the
orobranchial cavity creates a flow of water into
the fishes mouth.
Jaw mobility in teleosts

The mobility of the maxilla and premaxilla allows
the upper jaw to extend and protrude from the
mouth.

Jaw protrusion is achieved by levering forward
the premaxilla from behind.

The premaxilla is attached with ligaments that
allow the bone to slide forward on top of the
skull.
http://141.213.176.11/site/accounts/information/Actinopterygii.html
Jaw mobility in teleosts

In a feeding fish this protrusion is accompanied
by other movements of the orobranchial cavity
[mouth and gill cavities], the head is raised, jaw
lowered and the opercula are moved laterally.

The net result of all these movements is a
sudden expansion of the volume of the oral
cavity that quickly sucks water (and prey) into
the mouth.
Lake Victoria cichlid
http://www.petfishtalk.com/shows/090325.htm
Jaw mobility in teleosts

Based on anatomical comparisons of their
structure in different groups it is clear that
protrusible jaws have evolved independently
multiple in different teleost clades.

Jaw protrusion is widespread among the
perciform fishes, but also occurs in silversides,
cods and anglerfishes, and in minnows.
Pharyngeal Jaws
 Mobile
and often powerful pharyngeal jaws
have evolved several times in
actinopterygians.
 Ancestral
ray finned fishes possessed
many dermal tooth plates within the
pharynx. Some toothplates over time
became fused together and to parts of
some gill arches.
Pharyngeal jaws
 The
earliest pharyngeal jaws were not very
mobile, but could be used to hold prey
before swallowing. Today a variety of
pharyngeal jaws occur in different groups.
 For
example, in minnows the primary jaws
lack teeth but the pharyngeal jaws are
enlarged and close against a horny pad on
the base of the skull. They are used to grind
plant material.
Pharyngeal jaws
 In
many groups the upper and lower
pharyngeal jaws can move independently
of each other.
 For
example, in some moray eels the
pharyngeal jaws can be extended from the
throat into the oral cavity to grasp prey and
pull it into the throat and esophagus.
These X-rays show the normal position of the pharyngeal jaws (upper), and
how they can move forward into the mouth to seize food (lower).
(Credit: Rita Mehta, Section of Evolution and Ecology and Candi Stafford,
School of Veterinary Medicine, UC Davis.)
Legend pasted from http://www.sciencedaily.com/r
eleases/2007/09/070905134523.htm
Moray Eel Pharyngeal jaws
http://en.wikipedia.org/wiki/File:Pharyngeal_jaws_of_moray_eels.svg
Pharyngeal jaws

The cichlids of Lakes Victoria, Malawi and
Tanganyika have diversified enormously into
about 500 species in a period of only about
14,000 years.

The possession of pharyngeal jaws which can
process food has allowed the outer jaws to be
greatly modified to consume a wide variety of
prey. Foods consumed include, other fish,
plankton, algae, fish scales, bivalves, and
diatoms.
http://cichlid.umd.edu/cichlidlabs/kc/res/Cichlid.html
Teleost classification
 How
the Neopterygii should be subdivided
differs greatly from authority to authority.
 We
will use a recent classification that
divides the teleosts into a dozen
superorders (some very large)
Infraclass Teleostei
Superorder Elopomorpha
[eels, tarpon, bonefish]
Superorder Clupeomorpha
[herrings, anchovies]
Superorder Ostariophysi
[carp, piranha, catfishes, electric eels]
Superorder Protacanthopterygii
[salmon, pike]
Superorder Paracanthopterygia
[cod, anglerfish, toadfish]
Superorder Acanthopterygi
[perch, tuna mackeral]
Superorder Osteoglossomorpha
[elephant fishes, Arapaima]
Five other superorders of
relatively small numbers of
fishes
The other five superorders
Infraclass Teleostei
Superorder Stenopterygii
[jellynose fish, hatchet fishes]
Superorder Cyclosquamata
[Bombay duck, lancetfishes]
Superorder Scopelomorpha
[lanternfishes]
Superorder Lampridiomorpha
[oarfish, ribbonfishes]
Superorder Polymixiomorpha
[beardfishes]
Superorder Elopomorpha

Elopomorpha: includes tarpons, bonefishes, and eels.

Specialized laterally compressed and transparent
leptocephalous [Greek slim headed] larvae are a unique
feature of the group.

Unlike most fish larvae they grow large (6-30cm) and are
good swimmers.

They have a long larval life of 3 months to a year adrift
on the ocean being moved by ocean currents.
http://en.wikipedia.org/wiki/Leptocephalus
Eel leptocephalus larvae
http://www.australianmuseum.net.au/image/Eel-leptocephali/
Bonefish
http://www.islaculebra.com/puerto-rico/fishing.html
Tarpon
http://www.wildernessaccess.com/images/
fishn/Tarpon-FISH-JustinS-America-Venezuela-Los-Rogos.jpg
Tarpons

There are two species of tarpon, one found in the
Atlantic and Caribbean (“the” tarpon or Atlantic tarpon)
and the Indo-Pacific tarpon.

One of the most popular of game fishes they grow 5-8’ in
length and weigh 80-280lbs. They put up a tremendous
fight when hooked and will leap high from the water.
Generally caught and released as they don’t taste great.

An ocean fish, but tolerant of brackish and even
freshwater. The swim-bladder serves as an accessory
breathing organ and this enables tarpon to tolerate lowoxygen conditions.
Eels
 Most
elopomorphs are eel-like and marine,
but some tolerate freshwater.
 The American
eel has a very unusual lifecycle. The eels grow to sexual maturity in
rivers and streams (taking 10 years or
more) and then migrate downriver into the
ocean to breed. (They are catadramous.)
Eels

They swim to the Sargasso Sea (an area of the
North Atlantic between the Azores and West
Indies) where they apparently spawn and die,
presumably at depth.

Eggs and larvae float to the surface and drift on
the currents until they reach the near the coast.
Then they transform into miniature eels and
travel up rivers to mature.
http://www.richardcorfield.com/assets/images/silent_landscape/sargasso.jpg
American Eel
http://www.peacefulparks.org/800x600/eels/
Anguilla-rostrata-2.jpg
Eel larvae
http://media-2.web.britannica.com/eb-media/17/54217-004-411C3896.gif
Eels

European eels also spawn in the Sargasso Sea.
Their larvae travel on clockwise currents mainly
of the Gulf Stream and are distributed to North
Africa, Northern Europe, the Mediterranean and
as far as the Black Sea.
 Because they drift in cooler waters, European
eels grow more slowly than American eels.
Development is slowed less than growth
however, and as a result European eels have
more vertebrae than American eels.
Superorder Clupeomorpha

Are a commercially very important group of about 360
species of mostly marine schooling, silvery fishes.

They include herring, shad, pilchards, anchovies and
sardines and schools can be enormous and provide an
important food source for many larger marine predators
including sharks and dolphins.

They feed on plankton which they gather using a
specialized mouth and gill-straining apparatus. Teeth are
small or absent.
Superorder Clupeomorpha
 Clupeomorphs
lack a lateral line and are
physostomous, which means there is a
direct connection between the swim
bladder and the gut.
 Most
are quite small -- size range is from 2
to 75cm.
Herring
http://pond.dnr.cornell.edu/nyfish/clupeidae/blueback_herring.jpg
Reef fish attacking a school of
Pacific herring
 http://www.youtube.com/watch?v=oBhK0_
HjVe0
Superorder Ostariophysi

Ostariophysi (from Greek for bone and bladder).

The second-largest superorder of fish and includes
about 28% of all living fishes and almost 70% of
freshwater species. Total number of species is estimated
at about 7900 species. Worldwide distribution except for
Antarctica and New Zealand.

Catfish, Cyprinids [minnows and carp], electric eels,
piranhas.

Display very diverse traits, but many have protrusible
jaws and pharyngeal teeth act as second jaws.
Superorder Ostariophysi

Members of the group possess two unique
derived features:



alarm substances in the skin and
the Weberian apparatus.
When the skin is damaged, pheromones are
released into the water and these stimulate a
fright reaction in other members of the species
and other ostariophysians. In response, they
may quickly seek cover or school together.
Weberian Apparatus

Weberian apparatus: The name ostariophysian
(Greek: bone and bladder) refers to a series of
small bones that connect the swim bladder with
the inner ear.

The Weberian apparatus greatly enhances
hearing in these fish and as a result they are
more sensitive to sounds and can hear a wider
range of sounds than other fishes.
Weberian apparatus

When sound waves strike the swimbladder it
vibrates.

A bone (the tripus) in contact with the swim
bladder then conducts this vibration via
ligaments to two other bones, the second of
which moves and compresses a section of the
inner ear against a fourth bone.

This fourth bone (the claustrum) then stimulates
the auditory region of the inner ear.
Weberian apparatus:
http://www.aqua.org.il/pic/Articles/CatFish/12.JPG
Cyprinids

The cyprinids are one of the largest families of the
Ostariophysi (about 2,400 species) and the group
includes the carp, goldfish and minnows.

The cyprinids lack a stomach and their jaws are
toothless. Instead they depend on their pharyngeal teeth
to chew food against a chewing plate formed from an
extension of the skull.

The pharyngeal teeth are sufficiently strong that fish
such as carp are able to consume hard shelled prey
such as snails and mussels.
Carp
 Colloquially
carp refers to the largest
species of cyprinids and these have a
close historical association with humans
having been farmed for food especially in
Eastern Europe and Asia and as an
ornamental fish for centuries.
Carp
http://www.naturephoto-cz.com/photos/
others/carp-20524.jpg
Goldfish and koi carp are among the most well known of the ornamental carp
Koi carp http://www.aqua-fish.net/show.php?h=koi
Catfish
 About
1,800 species. Named catfish for
the prominent barbels (as many as 4
pairs) that many species have, which
resemble a cat’s whiskers and are used
for food finding.
http://fishingforbeginners.net/
how-to-catch-catfish/
Catfish

Freshwater fish found worldwide. Most are
bottom-feeders and are negatively buoyant
having a small swim-bladder and a heavy
flattened head.

Catfish (like carp) have been widely caught and
farmed for centuries. They can easily be raised
in large ponds in warm climates and there is a
large catfish aquaculture industry in the southern
U.S.
Catfish
 Many
species are quite small reaching
only 4” in length, but others can be
enormous. The largest is the giant
Mekong catfish that has been known to
reach over 10’ long and a weight of
650lbs. This is the record for the world’s
largest freshwater fish.
http://news.nationalgeographic.com/news/2005/06/photogalleries/giantcatfish/
Catfish

Most catfish possess a strong hollow spine-like
ray on their dorsal and pectoral fins. These can
be locked in place as a defensive mechanism
and can inflict severe wounds. Some species
produce a toxic protein that can be delivered by
these spines. In a few species the toxin is
dangerous and in rare cases lethal to humans.
Piranha
 Piranha
belong to the family Characidae in
the Ostariophysi. They are south
American fish and occur in the large river
basins of the Amazon, Orinoco and similar
rivers. Estimates of the number of species
range from 30-60 species
 They
are known for their sharp teeth and
have a fearsome reputation as carnivores.
Piranha

They are relatively small deep-bodied schooling
fish 5-10” long and easily recognized by their
dentition. They possess a single row of sharp
triangular teeth in both the upper and lower
jaws.

The piranhas (specifically one species the redbellied piranha) reputation for ferocity appears to
have been greatly exaggerated, but attacks on
humans do occur especially in situations where
in shallow water where fishing and gutting is
taking place.
Piranha
http://blogs.westword.com/latestword/
piranha.jpg
http://www.paradiseearth.com/
Animal%20Articles/Piranha.html
Piranha clip
 http://www.youtube.com/watch?v=4frRbnl5
0HU
Superorder Protacanthopterygii

The superorder includes about 500 species of
which the esocid [pike] and salmonid fishes are
the most familiar.

The group originated about 150 mya and
numerous fossils are known from the
Cretaceous.

They are a temperate water group and most
species are found in the northern hemisphere.
Superorder Protacanthopterygii

Many Protacanthopterygii (e.g. salmonids)
possess an adipose fin, which is a soft fleshy fin
found on the back behind the dorsal fin and just
forward of the caudal fin.

Function of this fin is unclear, but trout that have
had it removed have an 8% higher tailbeat
frequency and it has been suggested that it may
have a sensory function in detecting sound,
touch and changes in pressure.
Adipose fin
Coho salmon
http://www.reelsilvercharters.com/lake-ontario-game-fish.htm
Superorder Protacanthopterygii

The salmonids include salmon, trout, char and
grayling and the group includes many
commercially important species.

The smallest salmonids are only about 5” long,
but some salmon can reach 6’ in length.

Many species of salmon are anadromous and
spend their adult lives at sea, but all salmonids
spawn in freshwater.
Rainbow Trout:
http://animals.nationalgeographic.com/
staticfiles/NGS/Shared/StaticFiles/
animals/images/primary/rainbow-trout.jpg
Coho Salmon
http://bullsheet.files.wordpress.com/2008/10/coho-salmon.jpg
Superorder Protacanthopterygii
 Trout
are close relatives of salmon, but
usually live their entire lives in freshwater.
 Salmon
and trout are important
commercial and recreational species.
 Salmon
have been a major focus of the
aquaculture industry.
http://www.canned-salmon.com/wp-content/uploads/2011/04/salmon_farm.jpg
Superorder Protacanthopterygii

The esocids are a small order (only 10 species )
which is closely related to the salmonids and
among the most primitive of euteleosteans.

They include pike, muskellunge, pickerels and
relatives.

These fish (which superficially resemble gars)
are voracious, stealth-hunting predators and
important freshwater game fish in North America
and northern Eurasia.
Muskellunge
http://www.rudybenner.com/Cochrane%20District%20Scuba%20Divers_files/
Muskellunge.jpg
Pike

Pike have a long, powerful muscular body and
an elongated snout filled with long pointed teeth
on which it impales its prey.

They have deeply forked tails, and paired dorsal
and anal fins set well back on the body. These
appear to be adaptations for rapid straight line
acceleration.

Pike typically lie in wait and suddenly rush from
cover to capture their prey.
Northern Pike
http://www.naturephoto-cz.com/photos/others/northern-pike-20529.jpg
Superorder Paracanthopterygii
 Includes
about 1,340 species of cod,
toadfish and anglerfish.
 An
almost exclusively marine group that
ranges in length from a few cm to about 2
meters.
Gadiformes

Cod and their relatives (including pollock, ling, hake, and
haddock) totaling about 475 species are cold water
marine fishes and the basis of some of the most
historically important marine fisheries.

Cod are the largest of the gadoids and may weigh up to
90 kg. They are mostly bottom dwellers and occur on
the continental shelves from shallow water to 200
fathoms.

Cod migrate over long distances and assemble in large
numbers to spawn. A single female may produce
millions of eggs, which drift in the plankton.
Atlantic Cod:
http://www.codgen.olsvik.info/Images/Cod7.jpg
Anglerfishes

Anglerfishes are named for their method of foraging
which involves using a lure to attract fish close to them.

The lure is a modified spine of the anterior dorsal fin and
can be wiggled like a prey item.

In deep sea anglerfish the lure contains bioluminescent
bacteria that help attract prey from a distance.

Some bottom-dwelling anglerfish depend on camouflage
and these fish have arm-like pectoral fins that they use
to move long the bottom.
Anglerfish
http://scribalterror.blogs.com/scribal_terror/images/2007/06/17/angler_fish.jpg
Black devil Anglerfish
http://oceanexplorer.noaa.gov/explorations/04deepscope/background/
deeplight/media/fig3b_600.jpg
Superorder Acanthopterygii

Includes two major groups:


Atherinomorpha and
Perciformes.

Atherinomorpha: More than 1,600 species of silversides,
killifishes, grunions, flying fish and relatives.

These are mostly small silvery fish that are surface
feeders.

There are about 50 species of flying fish (mostly tropical)
that are members of the Atherinomorpha and they use
their enlarged pectoral fins to glide 50 to 400m
(depending on updrafts from waves) to escape predators.
Silversides
http://www.aboututila.com/Photos/AdamLaverty/Fish-Silversides.JPG
Flying fish
http://blogs.dispatch.co.za/dispatchnow/files/2008/01/flying-fish.jpg
http://myanimalblog.files.wordpress.com/2008/02/flyingfish.jpg
Acanthopterygii

The second major group is the Perciformes: more than
7,000 species of perch and their relatives.

Range in size from 7mm to 5m long. A paraphyletic
group there is no set of derived traits that groups them
all together, but they usually have dorsal and anal fins
with anterior spiny portions, whereas the posterior spines
are usually soft rayed. The two portions may be partially
or completely separated.

Snook, sea bass, sunfish, perch, darter, snapper,
cichlids, barracuda, tuna, most coral reef fish.
European Perch
http://www.strikeit.net/USERIMAGES/PERCH.JPG
Black Seabass
http://shiftingbaselines.org/blog/
images/Black%20Sea%20Bass2.jpg
Snook
http://www.floridaadventuring.com/images/snorkeling-school-of-snook.jpg
http://www.practicalfishkeeping.co.uk/pfk/
images/cc_barracuda_national_park_service.jpg
Barracuda
http://www.bubblevision.com/albums/richelieu-rock/images/giant-barracuda.jpg
Infraclass Osteoglossomorpha

Osteoglossomorpha: [greek bony tongue].
About 220 species of tropical freshwater fish.
Includes from the Amazon Osteoglossum or
Arawana, and Arapaima among the largest
purely freshwater fish (regularly 3m long, but up
to 4.5 m).

Also includes the African elephant nose fish,
which are bottom feeders and that use weak
electric signals to communicate with each other
Arawana
http://media-2.web.britannica.com/eb-media/28/117528-004-6B4BBA33.jpg
Arapaima
http://www.petfishtalk.com/rss_feeds/images/080326_arapaima_1.jpg
Elephant nose fish
http://images.google.com/imgres?imgurl=http://www.bio.davidson.edu/people/
midorcas/animalphysiology/websites/2003/Wilson/cfunspics/
elephant_nose.jpg&imgrefurl=http://www.bio.davidson.edu/people/midorcas/
animalphysiology/websites/2003/Wilson/
GalONE.htm&usg=__yE31La06_D121J4Yga5NHWknr5Y=&h=467&w=1458&sz
=57&hl=en&start=3&tbnid=xQ3Vx636CuW21M:&tbnh=48&tbnw=150&prev=/
images%3Fq%3Delephant%2Bfish%26gbv%3D2%26hl%3Den%26sa%3DG