Xenodon merremii

Xenodon merremii, also known commonly as Wagler's snake, is a species of snake in the subfamily Dipsadinae of the family Colubridae. The species is endemic to South America and is widespread in the eastern half of the continent.

Geographic range
X. merremii occurs in Venezuela, Guyana, Suriname, French Guiana, Brazil, Bolivia, Paraguay, Uruguay, and northern Argentina.

Etymology
The specific name, merremii, is in honor of German herpetologist Blasius Merrem.

Description
Adults of X. merremii are usually 1 m or less in total length (including tail). Its color pattern is very variable. Some "red phase" specimens are a uniform reddish tan. Other specimens are pale brown dorsally, with broad dark-brown crossbands, which are edged with black, and are narrower or interrupted in the middle. The latter color pattern resembles that of the venomous snake Bothrops alternatus.

Diet
X. merremii preys on insects, frogs, toads, lizards, and sometimes snakes. Like other rear-fanged toad-eaters of the genera Heterodon and Lystrophis, X. merremii uses its enlarged posterior maxillary teeth to puncture and deflate toads which have defensively puffed themselves up, thereby making them easier to swallow.

Defensive behavior
When threatened, X. merremii raises the anterior part of its body, inflating and spreading its neck, similar to a cobra.

Reproduction
X. merremii is oviparous.