here is a cool flow chart to figure out differnt species of sharks.
www.dfw.state.or.us...
Key to Sharks, Rays, and Skates
1.a. Dorsally compressed (flat with eyes on top of head) with very large pectoral fins. Tail long and narrow - go to 13 (Rays and Skates)
1.b. Not dorsally compressed. Tail with distinct caudal fin - go to 2 (Sharks)
2.a. Has 2 dorsal fins - go to 4
2.b. Has 1 dorsal fin and 1 anal fin; teeth on lower jaw are saw-like- go to 3
3.a. Has 7 gill slits, black spots scattered over body - Sevengill Shark (Notorynchus cepedianus) (2.7 m / 9 ft) - rare species
3.b. Has 6 gill slits, no spots on body- Sixgill Shark (Hexanchus griseus) (4.7 m / 15.5 ft) - rare species
4.a. No anal fin present - go to 5
4.b. Anal fin present - go to 6
5.a. Has a single spine in front of each of the two dorsal fins. Snout pointed. White spots usually cover body - Spiny Dogfish (Squalus acanthias)
(1.6 m / 5 ft) - uncommon species
5.b. No spines in front of dorsal fins. Snout rounded. Eyes small. Appears flaccid when out of water. No white spots on body - Pacific Sleeper
Shark (Somniosus pacificus) (4.4 m / 14.5 ft) - rare species
6.a. Upper lobe of tail huge (more than half the length of the body) - Common Thresher Shark (Alopias vulpinus) (6.1 m / 20 ft) - rare species
6.b. Upper lobe of tail less than 1/4 length of body - go to 7
7.a. Body covered with broad dark bars, saddles, and spots - Leopard Shark (Triakis semifasciata) (2.1 m / 7 ft) - rare species
7.b. Few or no spots on body - go to 8
8.a. Body robust. Second dorsal fin tiny (less than 1/4 of the size of first dorsal fin). One or more lateral caudal keels - go to 9
8.b. Body slender. Second dorsal fin greater than 1/4 of the size of the first dorsal. No lateral caudal keels - go to 11
9.a. Pectoral fins long. Single caudal keel. Long conical pointed snout - Bonito Shark (Shortfin Mako) (Isurus oxyrinchus) (3.8 m / 12.5 ft) - rare
species
9.b. Snout bluntly conical - go to 10
10.a. Has black spot at base of pectoral fin. Single caudal keel - White Shark (Carcharodon carcharias) (9.1 m / 30 ft) - rare species
10.b. Has black spot at base of pectoral fin. Large blotches of gray or black on belly in adults. Second caudal keel behind and below first keel -
Salmon Shark (Lamna ditropis) (3 m / 10 ft) - rare species
11.a. Terminal dorsal lobe of tail large, almost half the size of the dorsal lobe. Second dorsal fin directly over the anal fin - Soupfin Shark
(Galeorhinus galeus) (2 m / 6.5 ft) - rare species
11.b. Terminal dorsal lobe of tail less than a third of the size of the dorsal lobe - go to 12
12.a. Second dorsal fin ahead of anal fin - Brown Smoothhound (Mustelus henlei) (94 cm / 37 in) - rare species
12.b. Second dorsal fin directly above anal fin. Very long pectoral fins - Blue Shark (Prionace glauca) (3.8 m / 12.5 ft) - uncommon species
13.a. Row of three mid-body spines, and three rows of spines on tail. Snout short but distinctly pointed - California Skate (Raja inornata) (76 cm /
2.5 ft) - rare species
13.b. Single mid-body spine and row of single spine on the tail - go to 14
14.a. Single mid-body spine, and row of single spines beginning behind eye-spots and continuing out tail. Snout not distinctly pointed - Big Skate
(Raja binoculata) (2.4 m / 8 ft) - uncommon species
14.b. Single mid-body spine, and row of single spines beginning at origin of pelvic fins and continuing out tail. Snout long and distinctly pointed
- Longnose Skate (Raja rhina) (137 cm / 4.5 ft) - unusual species
[edit on 15-6-2009 by AKARonco]