A team of scientists has found in the Brazilian river Araguaia a specimen belonging to a new species of river dolphin, one of the strangest animals on the planet. It is the fifth species to be documented, and the first since 1918 . The snout animal would be part of a small population of 1,000 dolphins that subsists in the river basin despite the serious threat posed by hydroelectric plants.
Researchers at the Federal University of Amazona (Brazil) collected DNA samples from dolphins from the Araguaia and Tocantins rivers, and found that they were different from all other known species. Inia araguaiaensis differs from its closest relatives in the morphology of the skull and in that it has only 24 teeth per jaw compared to 29 of other species. Experts place its appearance about 2 million years ago, when the Araguaia-Tocantins basin separated from the rest of the Amazon river system and the inclemency of the current isolated part of the dolphins.
Freshwater cetaceans have long snouts that allow them to catch fish between submerged roots and in the mud of the river bed, and differ from saltwater dolphins in their smaller size. They can also be in multiple colors: white, pink, yellow, brown, gray or black.
This study has highlighted the great ignorance of the biodiversity of the area, since these mammals were easily visible, and the unawareness of the serious threat to which the native animals are exposed. In fact, scientists have already requested the International Union for Conservation of Nature to include this species on the Red List of potentially vulnerable animals.
