1. CLASS CHONDRICHTHYES

2. GENERAL CHARACTERISTICS
Moveable jaws (usually ventral) & well developed, replaceable teeth in 6-20 rows

3. Skeleton of a porbeagle shark
Cartilage skeleton

4. Rigid fins
Gill slits

5. Placoid scales – (same composition as teeth)
Dermal denticles

6. No swim bladder

7. SHARKS 350 sp. Mostly predators Some filter feeders Whale Shark
Great White Shark

8. Well developed caudal (tail) fin; often heterocercal
Well developed caudal (tail) fin; often heterocercal (upper lobe larger)
Can not force water over gills; constant swimmers
Exception: lemon & nurse sharks

9. Rows of teeth

12. Ampullae of Lorenzini
Electroreception device to sense bioelectrical fields of orgs

14. Andre Hartman – Crazy Shark Man

16. No swim bladder –
Large oily liver for buoyancy (20% body weight)

17. Fusiform (torpedo shaped) body = fast swimmer
Countershading – dark on top, light on bottom
Blue Shark

18. White Shark

19. Hammerhead Shark

20. Separate sexes; internal fertilization
Male
Female

21. Live Birth
Egg Cases

22. RAYS & SKATES
sp.
Flattened bodies; most benthic (demersal) exception – manta & eagle rays
Broad, wing-like pectoral fins for gliding through water

23. Ventral gills (5 pairs) & mouth
Bluntnose Stingray

24. Eat fish & invertebrates
Southern Stingray

25. RAYS VS. SKATES Whip-like tail with stinger & poison gland
NO whip-like tail & poison gland

26. Live Birth
Egg Case – Mermaid’s Purse

27. 14 foot freshwater ray in Thailand

28. 75 lb 5-6 foot spotted eagle ray kills woman in Florida (2008)

29. RATFISH 30 sp. Also called chimeras
Deep water (up to 3000 ft); feed on mollusks
Rabbit-like head; long rat-like tail
Large, triangular pectoral fins

33. THE END