eunectes murinus

from WordNet (r) 3.0 (2006)

Eunectes murinus
    n 1: large arboreal boa of tropical South America [syn:
         {anaconda}, {Eunectes murinus}]

from The Collaborative International Dictionary of English v.0.48

Anaconda \An`a*con"da\, n. [Of Ceylonese origin?] (Zool.)
   A large South American snake of the Boa family ({Eunectes
   murinus}), which lives near rivers, and preys on birds and
   small mammals. The name is also applied to a similar large
   serpent ({Python tigris}) of Ceylon.
   [1913 Webster]