A rare river dolphin has been officially classified as a new species.

The Bolivian river dolphin has been acknowledged as a separate species to the more widely-known Amazon River dolphin.

The formal announcement was made at a conservation workshop in Santa Cruz de la Sierra in Bolivia.

The Bolivian dolphin (Inia boliviensis) was immediately adopted by the Bolivian government as a symbol of the country’s conservation efforts.

The Bolivian species is smaller and a lighter grey in color than the other species and has more teeth. It lives only in the Bolivian Amazon and is isolated from the other Amazon River dolphins, separated by a series of 18 rapids between Bolivia and Brazil.

The boto or Amazon pink river dolphin (Inia geoffrensis) lives exclusively in the freshwater river systems of the Amazon and Orinoco Rivers. The largest of all river dolphins, botos vary from grey to pink and can even change colour, becoming pinker if very active.

Unusually for a dolphin, they have flexible necks and can turn their heads from side to side, weaving between the branches of flooded forests during the wet season.