The rarest boa on Earth has been discovered in the rapidly shrinking Atlantic Forest outside São Paulo.

Farmers discovered the 5.5-foot-long female in Ribeira Valley on January 21—the first live specimen of this species collected since 1953, according to photographer Jonne Roriz.

A public campaign to recruit locals to help find the reptile—a mystery to science for decades—had paid off. (Read about a new species of snake discovered in Australia.)

Robert Henderson, curator emeritus of herpetology at the Milwaukee Public Museum, says "this is an amazing find. Just phenomenal."

"Rather Bitey"

When farmers in the area known as Ribeira, see a snake, they generally kill it, as it may be deadly.

This strategy meant scientists at the University of São Paulo Museum of Zoology and the Institute Butantan only had dead specimens to study—about five over the past 64 years. (Take our poll: "Which of These Snakes Is the Fiercest of Them All?")

The snakes' bodies told researchers basic information about what the snake looked like (a light brown body with splotches of dark brown or black on its back) and its size, but little beyond that. Closely related species live in trees and can be “rather bitey,” according to Henderson.

“The snakes have to drag their prey from the ground up into the tree where they eat it, so they need to be able to hold on and not drop their food,” he says.

Scientific expeditions to the Ribeira Valley, where several Cropan's boas had been found decades ago, yielded nothing. (See National Geographic's pictures of snakes.)

View Images The newfound female snake, about 5.5 feet long, is a dexterous tree climber. Photograph by Jonne Roriz

"This Snake Was Theirs"

So the herpetologists began spreading the word.

Beginning in October 2016, Bruno Rocha, Daniela Gennari, and Livia Correia gave talks about the snake to communities and provided brochures with its photograph so locals could easily recognize it (preferably before dispatching it with a machete strike).

The team taught the locals how to scoop a snake into a bucket and provided them with an email, phone number, and WhatsApp contact information for the scientists.

Once the scientists inspected the live boa, they implanted her with a small radio tracker and released her back into the Ribeira Valley, where she may provide insight into the species' longevity and mating habits.

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