An international group of scientists announced the discovery of a new species of extinct freshwater dolphin that lived in the Amazon region about 16 million years ago. According to estimates, the body length of the animal was approximately three to three and a half meters. This is the largest river dolphin ever found.

River dolphins are considered one of the rarest modern marine mammals. Many of their species are threatened with extinction due to habitat loss due to human hunting and the generally small populations of these animals. Additionally, since river dolphins have very poor eyesight, they regularly encounter artificial objects that they cannot detect with the help of their sonar.

Scientists from the universities of Zurich (Switzerland), Toulouse (France), Caetano Heredia (Peru), the American Museum of Natural History (USA) and other scientific organizations examined the remains of the largest river dolphin ever found. Its dimensions range from 2.8 to 3.5 meters. This exceeds the size of modern river dolphins, which reach only 2.5 meters in length. However, the fossil (skull) was discovered in 2018, when the study’s lead author was an undergraduate student, but has only now been examined. This is the only example of a new species of river dolphin.

he was elected pebanistayacuruna – in honor of the legendary people who supposedly lived in the Amazon basin in the past. This is understandable because the remains of the animal were found in the Peruvian Amazon. According to estimates, the age of the dolphin is approximately 16 million years.

Attributed to the new species Platanistoidea — Groups of dolphins that lived in the World Ocean between 16 and 24 million years ago. As paleontologists hypothesize, marine ancestors began living in the freshwater Amazon, adapting to the new environment due to the abundance of prey living there. By the way, 16 million years ago the Peruvian Amazon did not look like it does today; Most of the Amazon lowland was covered by numerous lakes and swamps. But about 10 million years ago, the landscape began to change, leading to the extinction of many species that the Pebanistayacuruna river dolphins preyed on. According to researchers, this led to their extinction.

In addition to its size, the found dolphin has another interesting feature – relatives. It turned out that the closest of them live not in the Amazon, but in South Asia – these are representatives of the genus Platanista. These and others have highly developed cranial crests, which are specialized bone structures associated with echolocation. Cetaceans distinguish objects with the help of emitting high-frequency sounds. The thing is that river dolphins live in very cloudy water and they do not need vision this way – it is much more important than biosonars. ancestors pebanistayacuruna at one time they entered the territory of not only South America, but also South Asia, and then their lines diverged. The results of the study were published in the journal Science Developments.