Scientists find the world’s biggest snake yet, a new species of green anaconda Premium

New research upends scientific understanding of this magnificent creature, revealing it is actually two genetically different species.

The green anaconda has long been considered one of the Amazon’s most formidable and mysterious animals. Our new research upends scientific understanding of this magnificent creature, revealing it is actually two genetically different species. The surprising finding opens a new chapter in conservation of this top jungle predator.

Green anacondas are the world’s heaviest snakes, and among the longest. Predominantly found in rivers and wetlands in South America, they are renowned for their lightning speed and ability to asphyxiate huge prey then swallow them whole.

My colleagues and I were shocked to discover significant genetic differences between the two anaconda species. Given the reptile is such a large vertebrate, it’s remarkable this difference has slipped under the radar until now.

Conservation strategies for green anacondas must now be reassessed, to help each unique species cope with threats such as climate change, habitat degradation and pollution. The findings also show the urgent need to better understand the diversity of Earth’s animal and plant species before it’s too late.

Historically, four anaconda species have been recognised, including green anacondas (also known as giant anacondas).

Green anacondas are true behemoths of the reptile world. The largest females can grow to more than seven metres long and weigh more than 250 kilograms.

The snakes are well-adapted to a life lived mostly in water. Their nostrils and eyes are on top of their head, so they can see and breathe while the rest of their body is submerged. Anacondas are olive-coloured with large black spots, enabling them to blend in with their surroundings.