22. a. Head long and conical Go to 23 



b. Head blunt Go to 24 



23. a. 20-27 teeth in each upper and lower jaw; crowns of teeth often marked with many fine vertical 



wrinkles; body to about 8 feet (2.4 m). 



Rough-toothed dolphin, p. 135 

 b. 26-35 teeth in each upper and lower jaw; teeth smooth; body to about 5.6 feet (1.7 m); distribution 

 restricted to northern coast of South America, in the Guianas, and adjacent eastward territory 

 of Venezuela. 



Guiana dolphin, p. 132 



24. a. Teeth usually at front end of lower jaw only, 2-7 pairs (rarely teeth in upper jaw); all teeth may have 



fallen out of the lower jaw of older specimens or may be extensively worn; forehead with median 

 crease; dorsal fin tall and distinct to 15 inches (38. 1 cm); body to 13 feet (4.0 m). 



Grampus, p. 96 

 b. Teeth in both upper and lower jaws, 7 or more pairs, forehead with no median crease Go to 25 



25. a. Flippers large and paddle-shaped, ovate, and rounded on the distal end; dorsal fin tall and erect to 



6 feet (1.8 m) in males and 3 feet (0.9 m) in females; 10-12 teeth in each jaw; teeth to 1 inch (2.5 cm) in 

 diameter. 



Killer whale, p. 84 

 b. Flippers long and pointed Go to 26 



26. a. Dorsal fin located in forward one- third of body, very broad at the base; head bulbous. 



(Pilotwhale) Goto27 



b. Dorsal fin located near midpoint of back; headlong Go to 28 



27. a. Flippersone-fifthof body length, or more. 



Atlantic pilot whale, p. 91 

 b. Flippers one-sixth of body length, or less. 



Short-finned pilot whale, p. 94 



28. a. Flipper has distinctive hump on forward margin; 8-11 prominent teeth curved backwards and 



inwards, in each upper and lower jaw. 



False killer whale, p. 88 

 b. Flipper lacks distinctive hump on forward margin; 10-25 teeth in each upper and lower jaw Go to 29 



29. a. 8-13 teeth in each jaw. 



Pygmy killer whale, p. 138 

 b. 20-25 teeth in each upper jaw, 21-24 teeth in each lower jaw. 



Many-toothed blackfish, p. 142 



30. a. Beak short, usually less than about 1 inch (2.5 cm) ' Go to 31 



b. Beak more than 1 inch (2.5 cm) Go to 33 



31. a. Flippers very short; dorsal fin small and triangular; 38-44 teeth in each jaw; body to at least 8 feet (2. 4 



ml; distinct black stripe from beak to area of anus; in profile beak shows very little separation from 

 forehead. 



Fraser's dolphin, p. 120 ■ 

 b. Flippers long relative to body length; dorsal fin tall and distinctly falcate; 22-40 teeth in each jaw; in 



profile, beak shows distinct separation from forehead. {Lagenorkynchus sp.) Go to 32 



32. a. 22-28 teeth in each jaw; dorsal fin all black; body to about 10 feet (3. 1 m). 



White-beaked dolphin, p. 126 

 b. 30-40 teeth in each jaw (some animals have greater number in upper than in lower jaw); dorsal fin 

 part gray, part black; body to about 9 feet (2.7 m). 



Atlantic white-sided dolphin, p. 123 



33. a. 20-26 teeth in the upper jaws; 18-24 in the lower jaws; body to 12 feet (3.7 m); teeth may be 



extensively worn. 



Atlantic bottlenosed dolphin, p. 128 



b. 26 or more teeth in both upper and lower jaws Go to 34 



167 



