3. ACTINOPTERYGII
• Actino = rays , pterus=fins
• Ray finned fishes are so called because their fins
are webs of skin supported by bony or horny
spines (rays), as opposed to the fleshy, lobed fins
of the class sarcopterygii
• Contains most of the bony fishes that exist today
OSTEICHTHYES
SARCOPTERYGII
ACTINOPTERYGII
4. CHARACTERISTICS
• Fins are supported by fin rays only
• Scales- elasmoid – cycloid / ctenoid
• Only one external branchial aperture
• Tail is homocercal
• Operculum present
• no internal nares ( choana)
• Spiracle absent
• branchiostegal rays
• structurally distinctive pelvic and
pectoral girdles
7. CHONDROSTEI
• PRIMITIVE FISHES
• AIR BLADDER– PHYSOSTOMOUS
• HEAVY GANOID SCALES
• A SPIRACLE
• A HETEROCERCAL TAIL
• SPIRAL VALVE IN INTESTINE
• BONES OF UPPER JAW (MAXILLA AND PREMAXILLA)
FUSED TO CRANIUM
• NO INTEROPERCULAR BONE.
PNEUMATIC DUCT
CONNECTING THE GAS
BLADDER TO THE
ALIMENTARY CANAL
ACTINOPTERYGII
CHONDROSTEI
HOLOSTEI
TELEOSTEI
Superorder 1
9. POLYPTERIFORM CHARACTERISTICS:
1) five to eighteen dorsal finlets, each with a single
spine and one or more soft rays
2) four gill arches
3) spiracles large
4) two gular plates
5) branchiostegal rays absent
6) ganoid scales
7) maxilla fused to skull
Polypterus palmas
POLYPTERIFORMES :- BICHIRS ORDER 1
POLYPTERUS
10.
11. ACIPENSERIFORMES :— Sturgeons
ACIPENSERID CHARACTERISTICS:
1) five rows of bony scutes along body
2) four oral barbels
3) caudal fin heterocercal
4) gular plates absent
5) teeth absent in adults
6) pectoral fin with soft rays fused into an anterior spine-like
element
Acipenser medirostris
ORDER 2
12.
13.
14. ACIPENSERIFORMES :— Paddlefishes
Polyodon spatula
POLYODONTIDAE CHARACTERISTICS:
1) snout long, flat, paddle-like
2) body essentially naked, with few scales
3) spiracle above and behind eye
4) caudal fin heterocercal
5) gill cover extended posteriorly
6) snout and gill cover with
electro-sensory pores
19. LEPISOSTEIFORMES :— Gars
Lepidosteus
LEPISOSTEIFORM CHARACTERISTICS:
1) elongate jaws with fanglike teeth
2) bony, ganoid scales in oblique rows
3) row of median scales along the first ray of the dorsal, anal, & caudal fin
4) body elongate, with the dorsal and anal fins located posteriorly
5) pectoral fins low on body, pelvic fins abdominal
6) cheek with numerous bony plates
7) three branchiostegal rays
8) Abbreviate heterocercal tail
ORDER 1
8
elongate jaws bony plates pectoral fins
Abbreviate
heterocercal tail
Ganoid scales
20.
21. AMIIFORM CHARACTERISTICS:
1) body cylindrical, with long dorsal fin
2) single gular plate
3) caudal fin abbreviate heterocercal
4) ten to thirteen flattened branchiostegal rays
5) maxilla included in gape
6) males with prominent ocellus near upper base of caudal fin
7) cycloid scales
Amia calva
AMIIFORMES :— Bowfins
cycloid scales 7
ORDER 2
long dorsal fin
gular plate
Eye spot
25. TELEOSTEI
• Teleosts account for 96% of all living fishes, including
most major fishery species
• All modern fishes
• The group is defined by the homocercal tail; Teleostei
means "end-bone," referring to the specialized bones
(uroneurals) at the end of the vertebral column that
support the symmetrical caudal fin
• Paired fins –flexible & modified
• Improved mechanism of locomotion & feeding
• Scales—thin (cycloid& ctenoid),absent in some
Superorder 3
ACTINOPTERYGII
CHONDROSTEI
HOLOSTEI
TELEOSTEI
26. • The operculum consists of four bones, including the
interopercular bone ( absent from chondrosteans),
which is derived from a branchiostegal ray.
• The vertebrae are completely ossified and reduced in
number from those of chondrosteans. The vertebrae
are not solid structures but are cylinders of bone
supported by bridge-like structures. Because of their
structure, they are lighter and stronger as well.
• The swimbladder is reduced in size and functions
primarily as a hydrostatic organ.
28. Branchiostegal Rays
Chondrosteans
floor of the branchial cavity----rigid
movements of the operculum
Water across the gills
branchiostegal rays
bones in the floor of the branchial cavity
increased the efficiency of active pumping of water
across the gills.
This One branchiostegal ray on each side became
part of the gill cover, as the interopercular bone
This bone, a definitive feature of teleosts,increased
the size of the opercular cavity and large amount
of water that could flow across the gills
Teleosts
29.
30. Homocercal Tail
Related to the development of the
swimbladder and neutral buoyancy
eliminated the need for a
heterocercal tail to provide lift
homocercal tail is also
advantageous for fast-swimming,
pelagic forms (because it delivers
uniform thrust)
31. Jaws
Rigid toothed jaws Flexible toothless jaws
Biting and grabbing
Variety of feeding methods
Main bone of upper jaw --maxilla
premaxilla
Firmly united to skull
Free of strong attachment
Easily extended
Pharyngeal teeth
32. Teleostei
Osteoglossomorpha Elopomorpha Clupeomorpha Euteleostei
Infra divisions
•Bony tongues
•Proboscis like lower jaw
• Weak electric discharge
• example-Osteoglossum
•Mormyrus (elephant
fish)
•Body elongated eel like
•Leptocephalus larva
•Minute scales or absent
•Dorsal & anal fin long &
narrow
•Fins without spines
•Eg. Anguilla
•Herrings,sardines,
anchovies
•Cycloid scales
•Feed on plankton
•Fins without spines
•No weberian apparatus
•E.g. Hilsa ilisha
•True teleosts
•Majority of living
fishes
•Eg. Labeo , catla
,salmon, angler
fish,
Exocoetus
33. OSTEOGLOSSOMORPHA
elongate body
Large scales
dorsal and anal
fins long
African bonytongue (Osteoglossidae)
Elephant fish (Mormyridae)
Goldeye (Hiodontidae)
electric organs
bright gold-
silver irises
large eyes
34. ElOPOMORPHA
• Elongated eel like body
• Long dorsal and anal fin
fused with caudal fin
• Pelvic fins absent
• Leptocephalus larvae
present
• Fins lack spines
35. ClUPEOMORPHA
• most species school and
feed on plankton
• Silvery scales
• compressed
• keeled body
• a flexible mouth
• fine gill rakers
Anchovy (Engraulidae)
Sardine (Ciupeiclae)
36.
37. CYPRINIFORMES
• Body with cycloid scales
• Head is scale less
• WEBERIAN OSSICLES
• Jaws lack teeth
Labeo
cirrhinus
catla cyprinus
Goldfish (Carassius auratus)
38. Siluriformes
• The Catfishes
• Head bears sensory
barbles
• adipose fins
• Webberian appratus
head is usually flattened
mouth without big sharp teeth
body is without scales
Most have a stout spine leading each
pectoral and dorsal fin, which can lock into
place.
Some species have venom glands
associated with the spines
They lack intermuscular bones in the body.
Wallago attu
Mystus seenghala
39. CHARACTERISTICS:
1) four pairs of barbels
2) skin thick, scales and bony plates
absent
3) robust spine present in dorsal and
pectoral fins
4) dorsal fin usually with six soft rays
5) no teeth on palate
four pairs of barbels
Spine in dorsal and
pectoral fin
40. SALMONIFORMES: (Salmons, Trouts )
SALMONID CHARACTERISTICS:
1) fins comprised only of soft rays
2) adipose fin distinct
3) pelvic fins thoracic with axillary process
4) gill membranes extending far anteriorly, not fused with isthmus
5) scales small, cycloid
6) toothed maxilla forming part of gape
scales small, cycloid
41. ESOCIFORMES : Pikes and Pickerels
ESOCID CHARACTERISTICS:
1) body elongate
2) mouth large, snout produced, resembling a duck’s bill
3) palatine, dentary, and vomer with canine teeth
4) single dorsal fin and anal fin located far posteriorly
5) toothless maxilla included in gape
6) trunk lateral-line canal complete
7) ten to twenty branchiostegal rays
8) adipose fin absent
a lie-in-wait predator
42. STOMIIFORMES—Dragonfishes
• luminescent organs are present, including those
on the body and on the tip of the chin barbel (in
the barbeled dragonfishes), and large light organs
under the eyes
• deepsea predators
• fang-rich mouth
43. LOPHIIFORMES
• The illicium and esca develop from the first ray of the spinous dorsal
fin.
• Anglerfish are inactive forms with large heads and mouths
• small or absent scales,
• Edible “poor man's lobster”
illicium
esca
EG. LOPHIUS (ANGLER OR FISHING FROG)
44. BELONIFORMES: Needlefishes, Flyingfishes
• Cycloid scales
• the upper jaw fixed
• dorsal and anal fins located on the rear half of the body,
• abdominal pelvic fins with six soft rays
• lower caudal-fin lobe with more principal rays than the
upper lobe. They also lack fin spines
Exocoetus volitans
needlefish
45. Halfbeaks have an elongated Iower
jaw functions in directing small,
surface-oriented organisms into the
mouth
pointed and elongated bodies.
five to seven finlets behind both the
dorsal and the anal fins
Halfbeak
Needlefish
46. pectoral fins large and
wing-like
mouth small, upper and lower jaws short
lateral-line
canal low on
body
Cycloid scales
lower lobe of caudal fin
longer than upper lobe
Dorsal fin
EXOCOETUS
47. CYPRINODONTIFORMES
As a result of their surface orientation, these fishes are
frequently called top minnows. They are distinguished
from similar true minnows (Cyprinidae) by the presence of
small teeth in the jaws, and they are sometimes referred
to as the "tooth-carps" ( Cyprino-don, "carp-tooth").
these species are small omnivores, although many are such efficient predators
on insects that they are used for mosquito control and other species are
capable of digesting blue-green cyanobacteria
surface-oriented morphology, which enables them to pump the thin,
oxygen-rich layer of water at the air-water interface across the gills, an
especially useful ability for life in warm, stagnant waters.
They are renowned for their ability to live in conditions of extreme isolation,
temperature, and salinity
mosquitofish ( Gambusia
affinis and G. holbrooki) have
been widely used as
mosquito-control agents
52. DACTYLOPTERIFORMES : Flying Gurnards
pectoral fins
extremely long
bony armor
two keels
(enlarged
scales)
A) Dactylopterus volitans B) Dactyloptena peterseni
free inner rays
54. PERCIFORMES
• spines present in the dorsal, anal, & pelvic fins
• ctenoid scales
• pelvic fins with one spine and five rays
Sunfish Perches
55. ECHENIFORMES —Remoras
sucking disc
lower jaw projecting spineless
Cycloid scales
This disk is formed from the spiny dorsal fin and
contains 10 to 28 slat-like, .transverse ridges, which
are modified spines
57. XIPHIIFORMES—Billfishes & Swordfishes
elongate bill derived
from premaxillae
caudal peduncle with one
or two keels
lacking true spines
two anal fins
origin of dorsal fin
over operculum
58. SCOMBRIFORMES : Mackerels and Tunas
lateral keels
two dorsal fins
series of finlets
pectoral fins
pelvic fins thoracic
Euthynnus affinis
Shows schooling High in omega-3 oils
59. ANABANTIFORMES
• swimbladder extends into the caudal region
• The LABYRINTHINE ORGANS permit them to
breathe air
• build a nest of froth on the surface of the water
rounded tails
long anal fins
Climbing perch (Anabas testudineus),
61. PLEURONECTIFORMES—Flatfishes
• eyes on the same side of the head
• highly compressed body
• anterior placement of the dorsal-fin origin, long
dorsal- and anal-fin bases,
• Adults lack gas bladder
Pleuronichthys coenosus
Sole (Achirus, Pleuronectiformes).
62. TETRADONTIFORMES
• Body is covered with spines.
• release tetradoxin
EG. DIODON (PORCUPINE FISH)
Tetradon/ The globe/ Puffer fish
,
Inflate their body
63. Fishes -A Guide to Their Diversity
Philip a. Hastings, h.J. WALKER, and GRANTLY R. Galland
Fishes- An lntroduction to lchthyology 5th edition
Peter B. Moyle Joseph J. Cech1 Jr.
References
