Delphinus

Delphinus is a genus of oceanic dolphin, family Delphinidae, whose only living species is the common dolphin, Delphinus delphis, the most abundant cetacean in the world, with an estimated global population of about six million. As the type genus of the subfamily Delphininae, it is closely related to the bottlenose, humpback, striped and spinner dolphins, the Clymene dolphin, Fraser's dolphin, the tucuxi and the Guiana dolphin. The species was once divided into short-beaked and long-beaked forms treated as separate species, but genetic research found many long-beaked populations are not closely related to one another and often descend from short-beaked ancestors, so both are now generally regarded as ecotypes of a single species.