Eunectes murinus (derived from the Greek ???????? meaning "good swimmer" and the Latin murinus meaning "of mice" for being thought to prey on mice), commonly known as the green anaconda, is a non-venomous boa species found in South America. It is the largest, heaviest, and one of the longest known extant snake species. The term anaconda (without further qualification) often refers to this species, though the term could also apply to other members of the genus Eunectes. Other common names include common anaconda and water boa.