The green anaconda, Eunectes murinus, is a species of constrictor snake from the Boidae family. It is also called the "great anaconda", "giant anaconda" and "Barbour anaconda".
Young anacondas hunt from trees, but adults lie in wait in water, with just their eyes and nostrils poking up above the surface. They drown their prey as well as crushing it. Like most snakes, the green anaconda can unhinge its jaws and swallow animals as big as a goat. It digests slowly, which makes it vulnerable to its predators.
It is the heaviest snake in the world, even though it is not the longest.
Humans do not feature among its prey and no attack has ever actually been verified.