1. Dichotomous Keys

2. Our Example:
A Shark

3. Shark/Skate/Ray Classification Example: Great White
Kingdom Animalia Plylum Chordata Class Chrondrichthyes (Cartilaginous fish) Order Lamniformes (Mackerel sharks)
Family Isuridae (White shark, 2 mako, longfin, shortfin)
Genus Carcharodon (Greek=big tooth)
Species carcharias

4. Sharks
Use this labeled diagram to understand the terms needed to identify a shark.

5. Sharks key
1A Body shaped like a kite if viewed from the top-go to statement 12
1B Body not shaped like a kite if viewed from the top-go to statement 2

6. 2A Pelvic fin not present and nose shaped like a saw ..............................Saw shark
2B Pelvic fin present

7. 3A Has six gill slits...................Cow shark
3B Has five gill slits

8. 4A One dorsal fin..........................Cat shark
4B Two dorsal fins

9. 5A Mouth at the front of the head rather than back along underside of head Whale Shark
5B Mouth back along underside of head

10. 6A Head shaped like a T with eyes at ends of T..............................Hammerhead Shark
6B Head not shaped like a T

11. 7A Top half of caudal fin same as bottom half
7B Top half of caudal fin different from bottom half

12. 8A First dorsal fin very long-almost half the length of the body……
8A First dorsal fin very long-almost half the length of the body…….False Catsharks and Gollumsharks
8B Smaller first dorsal fin length

13. 9A Very long caudal fin, almost as long as whole body........................Thresher shark
9B Normal length caudal fin
……….

14. 12A Has small dorsal fin near tip of tail......Skate
12B No dorsal fin near tip of tail.....Stingray

15. Take a piece of looseleaf and number it 1-14
Use the class handouts to help you identify the Family names of the sharks on the handout
Do not write on the class set-answers will only be written on your looseleaf

16. Answers: 1.) Rajidae 2.) Aloplidae 3.) Pristophoridae
4.) Carcharhinidae
5.) Scyliorhinidae
6.) Rhinocodontidae
7.) Isuridae
8.) Squalidae
9.) Dasyatidae
10.) Scapanorhynchidae
11.) Pseudotriakidae
12.) Hexanchidae
13.) Sphyrnidae
14.) Mobulidae