Vivid snake species with blue lips and yellow eyes is new to science

A multicoloured venomous snake found in dry tropical forests in central Vietnam has been recognised as a new species. Trimeresurus cyanolabris has a bright grass-green body, yellow eyes, a brick-red tail and blue lips, chin and throat, and it has been dubbed the blue-lipped green pit viper.

The snake, which feeds on small frogs and lizards, is most active at dusk and after nightfall, spending the day perched on branches or in the hollows of trees near streams.

T. cyanolabris is one of 50 closely related Asian species of pit viper and can be distinguished by its colours and smaller size. Sabira Idiiatullina at Moscow State University in Russia and her colleagues used genetic analysis to confirm that the snake is a distinct, previously unrecognised species and that its closest known relative is the red-eyed Trimeresurus rubeus.

Genetic methods are likely to identify more Trimeresurus species – it is one of the most species-rich groups of venomous snakes known – but the forests where many of them live are at risk of deforestation.