Anaconda – Genus of snakes

Anacondas or water boas are a group of large boas of the genus Eunectes. They are a semiaquatic group of snakes found in tropical South America. Three to five extant and one extinct species are currently recognized, including one of the largest snakes in the world, E. murinus, the green anaconda.

Distribution and habitat

Found in tropical South America from Ecuador, Brazil, Colombia and Venezuela south to Argentina.

Feeding

All five species are aquatic snakes that prey on other aquatic animals, including fish, river fowl, and caiman. Videos exist of anacondas preying on domestic animals such as goats and sometimes even jaguars that venture too close to the water.

Relationship with humans

While encounters between people and anacondas may be dangerous, they do not regularly hunt humans. Nevertheless, threat from anacondas is a familiar trope in comics, movies, and adventure stories (often published in pulp magazines or adventure magazines) set in the Amazon jungle. Local communities and some European explorers have given accounts of giant anacondas, legendary snakes of much greater proportion than any confirmed specimen.

Although charismatic, there is little known on the biology of wild anacondas. Most of our knowledge comes from the work of Dr. Jesús A. Rivas and his team working in the Venezuelan Llanos.

Species

Rivas et al. revised the taxonomy of Eunectes, describing a new species of green anaconda (Eunectes akayima) and merging E. deschauenseei and E. beniensis with E. notaeus, which resulted in the recognition of only three species of anaconda. The result of their phylogenetic analysis is represented below:

Green anacondas

Eunectes murinus

Eunectes akayima

Eunectes notaeus

Eunectes notaeus

Eunectes notaeus

“Eunectes beniensis”

Eunectes notaeus

“Eunectes deschauenseei”

In a response paper, Dubois et al. questioned the results of the mtDNA analysis above and the validity of Eunectes akayima. The name of the new species was considered a nomen nudum.