Eunectes murinus; Print; The green anaconda (Eunectes murinus); also known as common anaconda or common water boa; is a non-venomous boa species found in South America. It is the heaviest and one of the longest known extant snake species. The term "anaconda" often refers to this species; though the term could also apply to other members of the genus Eunectes.; 1700-1880