1. Class: Osteichthyes
By- Sanju Sah
St. Xavier’s College, Maitighar, Kathmandu
Department of Microbiology

2. Order: Crossopterygii
-Extinct.
-Paired lobate caudal
fins. 3 lobed.
-Crossoi : fringe.
-pteryx : fin.
Eg: Latimeria

3. Order: Dipnoi
• Di – double , Pnoe – breathing.
• Air bladder single or paired.
• Lung like air bladder.
• Eg: all lung fishes.
Protopterus

4. Order: Polypteriformes
• Poly : many , pteri : fins.
• Presence of 8 finlets in dorsal fin.
• Lobed pectoral fins.
• Eg: Polypterus

5. Order: Acipenseriformes
• Cartilaginous fishes.
• Scaleless fishes.
• Body covered with 5 pairs of
Bony scutes.
• Endocranium is cartilaginous.
Eg: Acipenser

6. Order: Amiformes
• Thin overlapping cycloid scales.
• Premaxillary firmly articulated
with cranium.
• Eg: Amia

7. Order: Semionotiformes
• Snout and body elongated.
• Scales rhomboid , gonoid in
oblique rows.
• Eg: Lepidosteus

8. Order: Clupeiformes
• Well developed cycloid scales.
• Homocercal caudal fin.
• Werberian apparatus present.
• Air bladder connected with ear.
• Eg: Salmo

9. Class: Scopeliformes
• Presence of second dorsal fin
or adipose fin.
• Usually luminous organs present.
• Mouth with numerous teeth.
• Swim bladder absent.
• Eg: Harpodon

10. Class: Cypriniformes
• Air bladder with duct to
Pharynx.
• Werberian ossicles present
connecting ear and Air bladder.
• Air bladder also connected with
Alimentary canal.
• Eg: Labio

11. Class: Anguiliiformes
• Snake like fish.
• Scales vestigial or absent.
• Long dorsal and anal fin.
• Air bladder connected with intestine.
• Anguilla

12. Class: Beloniformes
• Elongated body.
• Cycloid scales.
• Ventral fins shifted to abdominal
sides.
• Some can fly.
• Exocoetus, Cypselurus

13. Class: Syngnathiformes
• Swim bladder closed.
• Protective bony rings.
• Tubular snout.
• Males with brood pouch.
• Hippocampus

14. Class: Ophiocephaliformes
• Ophio- snake, Cephalus- head.
• Cycloid scales.
• Depressed head.
• Accessory respiratory organ.
• Ophiocephalus

15. Class: Symbranchiformes
• Sym- jointed, branchia- gills.
• Eel like body.
• Gill slits jointed to form
transverse ventral slites.
• No air bladder.
• Symbranchus

16. Class: Mastacembeliformes
• Eel like body.
• Free spines infront of dorsal fin.
• Dorsal, anal and caudal fins united
to form A continuous fin.
• Mastacembelus

17. Class: Perciformes
• Perci- spines.
• Fins with spines.
• 2 dorsal fins.
• Werberian apparatus absent.
• Air bladder without duct.
• Anabas

18. Class: Scorpereniformes
• Enlarged head and pectoral fin.
• Spines projecting from gill
covering.
• Pterois

19. Class:Pleuronectiformes
• Bottom dwellers.
• Flat body. Lying on one side.
• Swim bladder absent.
• Both eyes on dorsal side.
• Synaptura

20. Class: Echeneiformes
• First dorsal fin modified
into flat oval adhesive disc.
• No air bladder.
• Echeneis

21. Class: Tetraodontiformes
• Strong jaw with sharp beak.
• Spiny scales usually present.
• Some inflate by swallowing water.
• Tetrodon

22. Thank You !