Peale's dolphin (Cephalorhynchus australis) is a small dolphin found in the waters around Tierra del Fuego at the foot of South America. It is also commonly known as the black-chinned dolphin or Peale's black-chinned dolphin. However, since Rice's work Peale's dolphin has been adopted as the standard common name.
Though it had traditionally been placed in the genus Lagenorhynchus, molecular analyses indicated Peale's dolphin is more closely related to the dolphins of the genus Cephalorhynchus. Some behavioral and morphological data supported moving Peale's dolphin to Cephalorhynchus. According to Schevill & Watkins 1971, Peale's dolphin and the Cephalorhynchus species are the only dolphins that do not whistle. Peale's dolphin also shares with several Cephalorhynchus species the possession of a distinct white "armpit" marking behind the pectoral fin. As a result, Peale's dolphin was reclassified as Cephalorhynchus australis in 2025.
Peale's dolphin is of typical size in its family — about 1 m (3 ft 3 in) in length at birth and 2.1 m (6 ft 11 in) when fully mature. Its adult weight is about 115 kg (254 lb). It has a dark-grey face and chin...