The document summarizes the key characteristics of the bony fish class Osteichthyes. Bony fish have a skeleton made of bone, scales, and an operculum covering their gills. They possess fins, swim bladders, and their mouths and jaws allow for better movement than sharks to aid feeding. Their internal anatomy includes two-chambered hearts, gills for gas exchange, lateral lines for sensing vibrations, and various sensory organs like eyes and ears. Bony fish exhibit diverse behaviors such as forming territories, schools, and undertaking migrations.

1. Bony Fish Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata Class: Osteichthyes

2. Class Osteichthyes “ Bony Fish” Skeleton made of bone Thin, flexible scales

3. Class Osteichthyes Operculum – a gill cover that protects the gills Swim Bladder – a gas-filled sac above the stomach allows for adjustments in buoyancy

4. Fins

5. Fins Upper and lower lobes of Caudal Fin almost always the same size Fin rays – rigid spines that support a thin membrane

6. Mouth & Jaws Mouth of most bony fish is terminal or anterior end Overall jaw movement is more than that of sharks with teeth that are fused to jaw

7. Feeding Most bony fish are carnivores Well developed teeth used for capture and holding Roof of mouth, gill rakers, and pharynx may have teeth to help hold

8. Feeding Grazers – fish that feed primarily on seaweeds and other plants Some develop beaks to help scrape off algae or pieces of coral

10. Feeding Filter feeders filter plankton through their gills Tend to be smaller, schooling fish such as herrings, anchovies, and sardines

11. Internal Anatomy

12. Digestive System Digestive System: stomach, intestine, pancreas, liver, pyloric caecae Pyloric caecae – slender tubes that secrete digestive enzymes Plant eaters = long intestine, Meat eaters = short intestines

13. Circulatory System Two chambered heart Gas exchange occurs in the gills

14. Gill Irrigation Gills share a common gill chamber Mouth opens, operculum closes, and pharynx expands to allow in water and the opposite is true Fast swimmers just open their mouths

15. Nervous System Brain & spinal cord Olfactory sacs or bulbs located on either side of the head and connected to nostrils (smell) Taste buds located in mouths or barbels

16. Vision Better eyes than chondrichthyes Fish eyes focus by moving closer or farther away from subject Many have color vision

17. Hearing Presence of inner ears Chambers similar to the lateral line Located on either side of the head just behind the brain Can resonate/amplify sound through swim bladder

18. Lateral Line Detects vibrations in water Small canals filled with sensory cells

19. Behaviors Territories – home areas that fish defend against intruders Most common in crowded environments Some defend as groups

20. Behaviors Schools – well defined groups of fishes Well coordinated with no leaders Used a protection by confusion Increase swimming efficiency Advantageous in feeding No single reason and vary species to species

21. Behavior Migration – regular mass movements from one place to another Anadromous fish – live mostly at sea and migrate to freshwater to breed (salmon) Catadromous fish – breed a sea and live in rivers (eels)

22. Subclass Dipnoi “ Lungfish” Jaw fused to brain case Caudal, dorsal, and anal fin connected Pectoral fins long and tubular Air breathing organ attached to esophogus

24. Subclass Crossopterygii “ Coelacanths” Cosmoid scale Two dorsal fins and fleshy paired fins with skeletal elements Thought to be extinct till found Sometimes grouped with lungfish in Subclass Sarcopterygii

27. Subclass Actinopterygii Ray-finned fishes Most familiar fish Have fin rays, swim bladders, and a symmetrically lobed caudal fin

28. Cartilaginous Fish Lungfish Ray-Finned Fish Lobed-Finned Fish Jawed Vertebrates Birds, lizards, turtles, dinosaurs, mammals

29. Subclass Actinopterygii Superorder Teleostei Bass Goldfish Guppies Seahorses Sturgeons Tuna Etc. Superorder Holostean Garpikes Bowfins Superorder Chondrostei Freshwater Sturgeon Bichirs Paddlefish Reedfish

30. Superorder Holostean Fin arrangements make for more efficient swimmers

31. Superorder Chondrostei Lack bone Sometimes classified with sharks Though more in common with the telosts

32. Superorder Telostei Most prolific class 96% of all fish 12 suborders Symmetrical caudal fin Spines on fins

33. Osteoglossmorpha Order Osteoglossiformes Order Hiodontiformes

34. Elopomorpha Order Elopiformes Order Albuliformes Order Notacanthiformes Order Anguilliformes Order Saccopharyngiformes

35. Clupeomorpha Order Clupeiformes

36. Ostariophysi OrderGonorynchiformes Order Cypriniformes Order Characiformes Order Gymnotiformes Order Silurioformes

37. Protacanthopterygii Order Salmoniformes Order Escociformes Order Osmeriformes

38. Stenopterygii Order Ateleopodiformes Order Stomiiformes

39. Cyclosquamata Order Aulopiformes

40. Scopelomorpha Order Myctophiformes

41. Lampridiomorpha Order Lampriformes

42. Polymyxiomorpha Order Polymixiiformes

43. Paracanthopterygii Order Percopsiformes Order Batrachoidiformes Order Lophiiformes Order Gadiformes Order Ophidiiformes

44. Acanthopterygii Order Mugiliformes Order Atheriniformes Order Beloniformes Order Cetomimiformes Order Cyprinodontiformes Order Stephanoberyciformes Order Bericiformes Order Zeiformes

45. Acanthopterygii Order Gobiescociformes Order Gasterosteiformes Order Syngnathiformes Order Synbranchiformes Order Tetraodontiformes Order Pleuronectiformes Order Scorpaeniformes Order Perciformes - 46% of fish