1. Is the body Fusiform or Depressed?
a. if depressed--------->2
b. if fusiform------------>5
2. Are the pectoral fins attached to the head?
a. yes ----------------->3
b. no-------------------> Order Squatiniformes (Angel Sharks)
3. More than one dorsal fin?
a. yes------------------>4
b. no------------------->Order Myliobatiformes (Manta and Sting Rays)
4. Produces electricity?
a. yes------------------>Order Torpediniformes (Electric Rays)
b. no------------------->Order Rajiformes (skates)
5. Number of gill slits
a. more than five------->Order Hexanchiformes (Frilled, Six Gill and Seven Gill Sharks)
b. five----------------->6
6. Eye position
a. in front of mouth---->7
b. behind the mouth----->Order Orectolobiformes (Carpet Sharks)
7. Anal fin?
a. no------------------->8
b. yes------------------->9
8. Does it have ventral gill slits and a dramatically elongated snout that resembles a saw blade?
a. yes------------------>Order Pristiformes (Sawfish)
b. no------------------->Order Squaliformes (Dogfish and Cookie Cutter Sharks)
9. Does it have different types of teeth in the front and back of its jaw?
a. yes------------------>Order Heterodontiformes (Horned Sharks)
b. no------------------->10
10. Do its eyes have nictitating membranes?
a. yes----------------->Order Charcariformes (Tiger, Bull, and Hammerhead Sharks)
b. no------------------>Order Lamniformes (Sand Tiger, Thresher, Megamouth, Basking, Mako, Goblin and Great White Sharks)
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