Types of pitvipers

Cerrophidion is a genus of pitvipers in the family Viperidae, the same family that includes rattlesnakes, copperheads, and the lanceheads. The genus name comes from the Spanish and Latin roots for hill or mountain, which fits how these snakes live. They are highland specialists, found in cloud forests, pine-oak woodland, and grassy clearings at high elevation. Our database holds 5 species, with members such as Wilson's Montane Pitviper, Godman's Montane Pit Viper, the Costa Rica Montane Pitviper, and the Tzotzil Montane Pit Viper.

As true pitvipers, all members of this genus carry the defining feature of the subfamily Crotalinae: a heat-sensing pit organ on each side of the head, set between the eye and the nostril. These pits detect the body heat of warm-blooded prey and let the snake strike accurately even in darkness. Like other vipers, they have a broad, somewhat triangular head distinct from a narrower neck, vertical pupils, and keeled scales that give the body a rough, matte look. They are generally stout, modestly sized snakes rather than long and slender.

These snakes are restricted to the highlands of Mexico and Central America, where the climate is cooler and wetter than the surrounding lowlands. Different species occupy isolated mountain ranges, which is part of why the genus is split into several look-alike forms separated by geography. They tend to be ground-dwelling, sheltering in leaf litter, under logs, among rocks, or in grassy tussocks, and they are most active in mild conditions rather than extreme heat.

Cerrophidion are venomous pitvipers and should be treated as capable of a medically serious bite. Their venom, like that of related vipers, can cause local pain, swelling, and tissue effects. Because they are secretive, well camouflaged, and live where people farm and hike, accidental encounters do happen. Never handle a wild venomous snake and never assume one is harmless because it is small or sitting still. If a bite occurs, treat it as a medical emergency, keep the person calm and the limb still, and contact emergency services or, in the United States, Poison Control at 1-800-222-1222 immediately.

Ecologically, these pitvipers are ambush predators that wait in cover for prey to pass, relying on camouflage and the heat-sensing pits to strike. Their diet centers on small vertebrates such as rodents, lizards, frogs, and similar prey available in mountain habitats. Like many New World pitvipers, they are believed to give live birth rather than lay eggs, a trait that suits cold high-elevation environments where eggs would struggle. Their behavior is mostly defensive: they prefer to stay hidden and will bite only when cornered or handled.