Platanistidae is a

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

river dolphin River dolphins are a polyphyletic group of fully aquatic mammals that reside exclusively in freshwater or brackish water. They are an informal grouping of dolphins, which itself is a paraphyletic group within the infraorder Cetacea. Extant rive ...

s containing the extant

Ganges river dolphin The Ganges river dolphin (''Platanista gangetica'') is a species of freshwater dolphin classified in the family Platanistidae. It lives in the Ganges and related rivers of South Asia, namely in the countries of India, Nepal, and Bangladesh. It ...

and

Indus river dolphin The Indus river dolphin (''Platanista minor'') is a species of freshwater dolphin in the family Platanistidae. It is endemic to the Indus River basin in Pakistan and Beas River in northwestern India. This dolphin was the first discovered side- ...

(both in the genus ''

Platanista South Asian river dolphins are toothed whales in the genus ''Platanista'', which inhabit the waterways of the Indian subcontinent. They were historically considered to be one species (''P. gangetica'') with the Ganges river dolphin and the Ind ...

'') but also extinct relatives from freshwater and marine deposits in the

Neogene The Neogene ( ,) is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period million years ago. It is the second period of th ...

. The

Amazon river dolphin The Amazon river dolphin (''Inia geoffrensis''), also known as the boto, bufeo or pink river dolphin, is a species of toothed whale Endemism, endemic to South America and is classified in the family Iniidae. Three subspecies are currently recogni ...

baiji The baiji (''Lipotes vexillifer'') is a probably extinct species of freshwater dolphin native to the Yangtze river system in China. It is thought to be the first dolphin species driven to extinction due to the impact of humans. This dolphin is ...

, and

La Plata dolphin The La Plata dolphin, franciscana or toninha (''Pontoporia blainvillei'') is a species of river dolphin found in coastal Atlantic waters of southeastern South America. It is a member of the Inioidea group and the only one that lives in the ocean ...

were once thought to belong to Platanistidae (e.g. Simpson, 1945), but cladistic and DNA studies beginning in the 1990s showed that the former three taxa are more closely related to Delphinoidea than to the South Asian river dolphin. The extinct odontocete families Allodelphinidae and Squalodelphinidae are closely related to Platanistidae. Fossils from this clade have been found in deposits in North and South America, Europe, and Central Asia. Fossil and modern members of Platanistidae, a family of dolphins, share distinctive features such as an elongated, narrow snout and a uniquely shaped bone near the cheek area. The family is divided into two subfamilies being the extinct Pomatodelphininae, known from Miocene marine deposits, and the extant Platanistinae, which includes the South Asian river dolphin ''Platanista gangetica''.

References

{{Authority control Mammal families Platanistoidea Taxa named by John Edward Gray Extant Miocene first appearances G. Barnes, L. (2006). A Phylogenetic Analysis of the Superfamily Platanistoidea (Mammalia, Cetacea, Odontoceti).