Family Phocoenidae - Porpoises (6 species in 4 genera)
Porpoises (members of the family Phocoenidae) are small cetaceans (all less than 2.5 m) that some taxonomists classify with the delphinids. They tend to be coastal in distribution, rather stocky in form, with either a short indistinct beak or no beak at all. Most have a short triangular dorsal fin and all have have spade-shaped teeth. In some species, females are larger than males. Phocoenids appear to live in smaller groups and have a simpler social structure than do most delphinids.
Genera
Genus Australophocaena containing 1 species:
Australophocaena dioptrica (Spectacled porpoise)
Genus Neophocaena containing 1 species:
Neophocaena phocaenoides (Finless porpoise)
Genus Phocoena containing 3 species:
Phocoena phocoena (Harbor porpoise)
Phocoena sinus (Vaquita)
Phocoena spinipinnis (Burmeister's porpoise)
Genus Phocoenoides containing 1 species:
Phocoenoides dalli (Dall's porpoise)