River dolphin

Polyphyletic grouping of dolphins

River dolphins also called Freshwater dolphins, are a polyphyletic group of fully aquatic mammals that reside exclusively in freshwater or even in brackish water. They are an informal grouping of dolphins, which itself is a paraphyletic group within the infraorder Cetacea. These dolphins are placed in three superfamilies, Platanistoidea (Platanistidae), Inioidea (Iniidae and Pontoporiidae) and Lipotoidea (Lipotidae).

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