(suborder Odontoceti, superfamily Delphinoidea)
A family that comprises the dolphins, killer whales, and pilot whales; relatively small cetaceans (1.5–9.4 m), the killer whale (Orcinus orca) being the largest member of the family. The dorsal fin is prominent except in Lissodelphinae (the subfamily of southern-right dolphins), in which it is absent. The first two or four, or all, cervical vertebrae are fused. Delphinids are distributed throughout all oceans. Tursiops truncatus (the bottle-nosed dolphin) is distributed widely in the northern Atlantic, and in Britain is prone to stranding. Globicephala melaena (pilot whale) is also prone to stranding, sometimes in large schools. The family comprises about 14 genera, and about 32 species.
Subjects: Zoology and Animal Sciences.