iRiver dolphins
Ganges River Dolphin Photographer:Brian D. Smith
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Superorder: Cetartiodactyla Order: Cetacea Suborder: Odontoceti Superfamily: Platanistoidea
Families
See text Image of the Ganges River Dolphin. ... Binomial name Platanista gangetica Subspecies Platanista gangetica gangetica Platanista gangetica minor Ranges of the Ganges River Dolphin and of the Indus River Dolphin The Ganges River Dolphin (Platanista gangetica gangetica) and Indus River Dolphin (Platanista gangetica minor) are two sub-species of freshwater or river dolphins found in the Indian... For other uses, see Scientific classification (disambiguation). ... Phyla Subregnum Parazoa Porifera Subregnum Eumetazoa Placozoa Orthonectida Rhombozoa Radiata (unranked) Ctenophora Cnidaria Bilateria (unranked) Acoelomorpha Myxozoa Superphylum Deuterostomia Chordata Hemichordata Echinodermata Chaetognatha Xenoturbellida Superphylum Ecdysozoa Kinorhyncha Loricifera Priapulida Nematoda Nematomorpha Onychophora Tardigrada Arthropoda Superphylum Platyzoa Platyhelminthes Gastrotricha Rotifera Acanthocephala Gnathostomulida Micrognathozoa Cycliophora Superphylum Lophotrochozoa Sipuncula Nemertea Phoronida Ectoprocta Bryozoa... {{{subdivision_ranks}}} See below Chordates (phylum Chordata) are a group of animals that includes the vertebrates, together with several closely related invertebrates. ... Orders Multituberculata (extinct) Volaticotheria (extinct) Palaeoryctoides (extinct) Triconodonta (extinct) Subclass Australosphenida Ausktribosphenida Monotremata Subclass Eutheria (excludes extinct ancestors) Afrosoricida Anagaloidea (extinct) Arctostylopida (extinct) Artiodactyla Carnivora Cetacea Chiroptera Cimolesta (extinct) Cingulata Creodonta (extinct) Condylarthra (extinct) Dermoptera Desmostylia (extinct) Dinocerata (extinct) Embrithopoda (extinct) Hyracoidea Insectivora Lagomorpha Leptictida (extinct) Litopterna (extinct) Macroscelidea Mesonychia... Orders Order Cetacea Order Artiodactyla Humpback Whale breaching. ... Suborders Mysticeti Odontoceti Archaeoceti (extinct) (see text for families) The order Cetacea includes whales, dolphins and porpoises. ... Families See text The toothed whales (systematic name Odontoceti) form a suborder of the cetaceans. ... In biological classification, family (Latin: familia, plural familiae) is 1) a rank or 2) a taxon in that rank. ...

River dolphins are four species of dolphin which reside in freshwater rivers and estuaries. They are classed in the Platanistoidea superfamily of cetaceans. Three species live in fresh water rivers. The fourth species, the La Plata Dolphin, lives in saltwater estuaries and the ocean. However, it is scientifically classed in the river dolphin family rather than the oceanic dolphin family. Suborders Mysticeti Odontoceti Archaeoceti (extinct) (see text for families) The order Cetacea includes whales, dolphins and porpoises. ... For the village on the Isle of Wight, see Freshwater, Isle of Wight. ... Binomial name Pontoporia blainvillei Gervais & dOrbigny, 1844 La Plata Dolphin range The La Plata Dolphin (Pontoporia blainvillei) is found in coastal Atlantic waters of southeastern South America. ... Estuaries and coastal waters are among the most productive ecosystems on Earth, providing ecological, economic, cultural, and aesthetic benefits. ... Genera See text Oceanic dolphins are the members of the Delphinidae family of cetaceans. ...

Ecology

River dolphins are some of the most endangered of all the world's cetaceans. Due to habitat loss, hunting by humans, and naturally low numbers, they are extremely vulnerable to extinction. Also, many river dolphins also possess very poor eyesight — some are considered blind — which can lead to unfortunate encounters with humans or manmade objects (boats or fishing nets for example). An endangered species is a species whose population is so small that it is in danger of becoming extinct. ... The Dodo, shown here in illustration, is an often-cited[1] example of extinction. ...

Some dolphin species can live in marine or riverine environments. The Tucuxi, for example, is equally at home in both ecotypes. However, these are not classified in the Platanistoidea superfamily and are therefore not regarded as true river dolphins. Binomial name Sotalia fluviatilis (Gervais & Deville, 1853) Tucuxi range The Tucuxi (Sotalia fluviatilis) is a dolphin found both in the rivers of the Amazon Basin and in the coastal waters to the north and east of South America. ...

Taxonomy

In the most recent classification (Rice, 1998) there are currently four extant families that make up the river dolphins - however it is almost certain that by the end of the decade the Lipotidae will have perished, it having been declared "functionally extinct" in December 2006. Platanistidae is listed as the only existent family of the Platanistoidea superfamily. The previously accepted classification treated all four families as belonging to this superfamily and treated the Ganges and Indus River Dolphins as separate species. In biological classification, family (Latin: familia, plural familiae) is 1) a rank or 2) a taxon in that rank. ... Binomial name Platanista gangetica Subspecies Platanista gangetica gangetica Platanista gangetica minor Ranges of the Ganges River Dolphin and of the Indus River Dolphin The Ganges River Dolphin (Platanista gangetica gangetica) and Indus River Dolphin (Platanista gangetica minor) are two sub-species of freshwater or river dolphins found in the Indian...

Classification by Rice (1998)

• Superfamily Platanistoidea
  • Family Platanistidae
    • Ganges and Indus River Dolphin Platanista gangetica
  • Family Iniidae
    • Amazon River Dolphin (or Boto) Inia geoffrensis
  • Family Lipotidae
    • Chinese River Dolphin (or Baiji) Lipotes vexillifer (presumed extinct as of 2006)
  • Family Pontoporiidae
    • La Plata Dolphin (or Franciscana) Pontoporia blainvillei

Binomial name Platanista gangetica Roxburgh, 1801 Ranges of the Ganges River Dolphin and of the Indus River Dolphin Subspecies Platanista gangetica gangetica Platanista gangetica minor Indus River Dolphin The Ganges River Dolphin (Platanista gangetica gangetica) and Indus River Dolphin (Platanista gangetica minor) are two sub-species of freshwater or river... Binomial name Inia geoffrensis Blainville, 1817 Boto range The Boto, Amazon River Dolphin or Pink River Dolphin[1] (Inia geoffrensis) is a freshwater or river dolphin. ... Binomial name Lipotes vexillifer Miller, 1918 Natural range of Lipotes vexillifer The Chinese River Dolphin (Lipotes vexillifer) was a freshwater dolphin found only in the Yangtze River in China. ... Binomial name Pontoporia blainvillei Gervais & dOrbigny, 1844 La Plata Dolphin range The La Plata Dolphin (Pontoporia blainvillei) is found in coastal Atlantic waters of southeastern South America. ...

Previous classification

• Superfamily Platanistoidea
  • Family Platanistidae
    • Ganges River Dolphin Platanista gangetica
    • Indus River Dolphin Platanista minor
  • Family Iniidae
    • Amazon River Dolphin (or Boto) Inia geoffrensis
  • Family Lipotidae
    • Chinese River Dolphin (or Baiji) Lipotes vexillifer (Presumed extinct as of 2006)
  • Family Pontoporiidae
    • La Plata Dolphin (or Franciscana) Pontoporia blainvillei

Extinction

On Dec. 13th, 2006, the Yangtze River Dolphin, or Baiji, was declared "functionally extinct", after a 45-day search by leading experts in the field failed to find a single specimen [1]. The last verified sighting of the beak-nosed dolphin was in September of 2004. [2] Binomial name Lipotes vexillifer Miller, 1918 Natural range of Lipotes vexillifer The Baiji (Traditional Chinese: ; pinyin: ) (Lipotes vexillifer, Lipotes meaning left behind, vexillifer flag bearer) was a freshwater dolphin found only in the Yangtze River in China. ...

It is believed that overfishing and sub-aquatic sonar pollution (which interfered with the dolphin's sonar-based method of locating food), led to the extinction. Reuters news reported this their first record of a mammalian extinction in "50 years".

References

• Rice, Dale W. (1998). Marine mammals of the world: systematics and distribution. Society of Marine Mammalogy Special Publication Number 4. 231 pp.