New Species of the 'World's Heaviest Snake' Discovered

A stock photo shows a Green Anaconda. Scientists have discovered a brand new species of the gigantic snake.

A new and genetically distinct species of green anaconda has been discovered by scientists.

The green anaconda is the heaviest, and sometimes longest, snake in the world. The boa species is found predominately in South America and can measure up to 20-feet long and weigh up to 550 pounds.

A group of multi-institutional scientists have now discovered that there is not just one species of green anaconda, but two, despite them looking almost identical. Their findings are detailed in a new study in Diversity.

“It was [a surprise] but in retrospect it shouldn’t have been,” Bryan G. Fry, a professor of toxicology at the University of Queensland, and researcher on the project, told Newsweek. “The Amazon is not one basin but two. The Amazon basin in the south and the Orinoco basin in the north.

“There have been a number of animals that have turned it to be separate species based on this geography. However even accounting for that it was still, and still is, a huge surprise that the two species of green anaconda differ by such a massive amount genetically. They are 5.5 percent different—we differ from chimpanzees by only 2 percent—and we also showed they split almost 10 million years ago. This really is mind-blowing.”

Fry said in an article on online network The Conversation that it is “remarkable” that this difference has “slipped under the radar” until now, considering how large and significant the species is.

While studying samples from anacondas from nine countries across 20 years they discovered “two genetically distinct species,” according to the article.

The first was the familiar Eunectes murinus species, also known as the southern green anaconda, that lives throughout Peru, Bolivia, French Guiana and Brazil.

The second, however, was newly discovered. Named Eunectes akayima, or northern green anaconda, it lives in Ecuador, Colombia, Venezuela, Trinidad, Guyana, Suriname and French Guiana.

“This had immediate conservation implications. As you may have seen in the last few months, the Amazon had been hit by a catastrophic drought. The big animals are the ones that are going to be affected the most. And there are none bigger than the green anacondas,” Fry said in the article. “Big snakes need big water. Since the newly described northern green anaconda has a much smaller range than the southern green anaconda, this puts it at the greatest risk from the impacts of climate change and other factors such as deforestation and oil spills.”

Green anacondas are constrictors, meaning they use their intensely strong bodies to suffocate and kill prey before swallowing it whole.

Despite their fearsome size, they are not considered dangerous to people and there are no confirmed cases of the species ever killing a human.

Green anacondas are incredibly important to their local ecosystem and very sensitive to changes in the climate. As their surrounding environment changes, Fry urges the need for better conservation efforts.

“Our immediate focus now is investigating the impacts of the frequent oil spills plaguing the Yasuni in Ecuador,” Fry said, “Oil spills release a myriad of chemicals, none worse than the heavy metals cadmium and lead. These have devastating effects upon fertility and also induce terrible and irreversible birth defects in developing foetuses. In addition to the direct effects upon these rare snakes, we in our ongoing research we are using anacondas as sentinel species. They are excellent indicators of health of an aquatic ecosystem since they are almost continuously in the water and unlike fish they don’t migrate.”

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