A team of scientists working with a National Geographic film crew in remote areas of the Amazon have discovered previously undocumented sightings of a giant anaconda. According to a study published in the journal MDPI Diversity The green anaconda Eunectes murinus are actually two genetically different species. And this is despite the fact that each species looks so similar that even experts cannot tell them apart.

A new species of snake was discovered during the filming of National Geographic’s “Pole to Pole” series with Will Smith. The film crew received a rare invitation from the chief of the Waorani hunting tribe to explore the area and collect specimens of the largest anaconda. Local hunters also took the scientists on a 10-day expedition into the forest in search of these snakes, which are considered sacred by the tribe. They canoed down the river system and managed to find several anacondas lurking in the shallow waters, waiting for their prey.

The sizes of the discovered creatures were significant: the length of one female reached 6.3 meters. According to unofficial information, the Waorani people noticed an anaconda in this region, 7.5 meters long and weighing approximately 500 kilograms. It is believed that even the largest anacondas can kill and eat a person. But such events have only been reliably documented in Asia, with snakes known as reticulated pythons.

Scientists managed to capture and study the found snakes. His colleagues also collected blood and tissue samples from green anacondas in Ecuador, Venezuela and Brazil. After analyzing the genetic data, the researchers found a clear difference between anacondas selected in the northern part of the range and those living in the south. The northern species of the green anaconda diverged from the southern green anaconda about 10 million years ago and differ genetically by 5.5 percent (by comparison, the human genome differs from the chimpanzee genome by only about two percent).

Based on the new data, the study’s authors recommend that the northern-dwelling snakes be renamed northern green anacondas Eunectes akaima, while E. murinus would still be called southern green anacondas.

In the future, scientists plan to understand how northern and southern green anacondas started on different evolutionary paths. These two species have lived side by side for millions of years, but there is no evidence of hybridization in their genetics. Additionally, the researchers’ focus is on examining the extinction risk of giant snakes in the Amazon.

Like other species living in this remote ecosystem, rare anacondas face significant environmental threats. Deforestation as a result of agricultural expansion in the Amazon basin has caused environmental losses of 20-31 percent and has the potential to affect 40 percent of forests by 2050. The described northern green anaconda has a much smaller range than the southern green anaconda, making it more vulnerable to extinction.

In conclusion, the discovery of a new species in the northern Amazon shows that we still know very little about the dynamics of gene flow in the world’s most diverse terrestrial ecosystem.