The Sun reports the 400kg reptile was discovered by workers after they carried out a controlled explosion in the Cave of Altamira, in the northern state of Para.
Video footage taken by one of the crew pans down the snake’s enormous body — which measures one metre in diameter.
After making the frightening discovery, the workers chained the animal to a crane and later lifted it up to reveal its yellow spotted under belly — a move which was criticised in the comments when the clip was uploaded to YouTube.
It’s claimed the builders killed the snake rather than leave it in its natural habitat, but this has not been confirmed.
Others believe the animal may have died in the explosion, possibly being hit by falling debris, as its head appeared flat in the video footage.
One user wrote: “I’m not sure this is real, but if it is, shame on these people for killing it! A snake that big has probably been alive for a very long time now, just to be killed for a few pictures? What a waste.”
Another said: “Human be like ‘oh look a giant rare snake and it maybe the last species on this earth, so lets kill it and show it to the world’.”
The Guinness World Record for the longest snake in captivity is currently held by Medusa, a snake in Kansas City, US, which is nearly eight metres long… see more