Crotalus polystictus

The Mexican lance-headed rattlesnake or lance-headed rattlesnake is a venomous pit viper species found in central Mexico. No subspecies is currently recognized.

Description

Adults usually grow to a total length of, although exceptionally large specimens may be as much as long.

The species is found on the plateau of central Mexico from southern Zacatecas and northeastern Colima east to east-central Veracruz. It occurs at elevations between. The type locality given is "Table Land, Mexico", although a restriction to "Tupátaro, Guanajuanto, Mexico" was proposed by H.M. Smith and Taylor.

This species is classified as Least Concern on the IUCN Red List of Threatened Species. Species are listed as such due to their wide distribution, presumed large population, or because they are unlikely to be declining fast enough to qualify for listing in a more threatened category. The population trend was down when assessed in 2007.