Snake Identifier
South American Bushmaster (Lachesis muta)
Bushmaster - Shushupe by Mauricio Espejo Chura, via Wikimedia Commons, licensed under CC BY-SA 4.0
Vipers

South American Bushmaster

Lachesis muta

The longest viper in the Americas, a massive pit viper of Amazonian rainforest with a distinctive spined tail.

Adult length
2.1-3.0 m (7-10 ft), occasionally longer
Range
Amazon Basin and surrounding forests of South America

Found a snake like this?

Identify any snake from a photo, free.

Identify a snake

Overview

The South American Bushmaster is the largest viper in the Western Hemisphere, a formidable pit viper inhabiting the dense rainforests of the Amazon Basin. It is rarely encountered due to its remote habitat and secretive habits.

Unlike most vipers, the bushmaster is oviparous, laying eggs rather than bearing live young, a distinctive trait among New World pit vipers.

How to identify it

  • Large, heavy body with tan to pinkish-brown background and bold dark diamond or triangular blotches
  • Broad, triangular head distinct from the neck
  • Heat-sensing pit between eye and nostril
  • Vertically elliptical pupils
  • Rough, keeled scales giving a coarse texture
  • Distinctive spine-like scale at the tip of the tail used to produce a rasping sound
  • Much larger than other Amazonian pit vipers such as the fer-de-lance

Habitat & range

Inhabits primary and undisturbed lowland tropical rainforest throughout the Amazon Basin and adjacent forested regions of South America, favoring areas with dense leaf litter and low human disturbance.

Behavior, diet & reproduction

Nocturnal and largely terrestrial, spending much of its time coiled motionless awaiting prey. Feeds on small to medium mammals via ambush predation. Oviparous, laying eggs and, unusually among vipers, exhibiting a degree of nest attendance by the female. Generally shy and avoids confrontation.

Frequently asked questions

Does it lay eggs or give live birth?

It lays eggs, which is unusual among New World pit vipers that typically give live birth.

Where does it live?

It inhabits undisturbed rainforest throughout the Amazon Basin and nearby forested regions.

Is it commonly encountered?

No, it is rarely seen due to its remote rainforest habitat and secretive, nocturnal habits.