The Mexican lance-headed rattlesnake[3] or lance-headed rattlesnake[4] (Crotalus polystictus) is a venomous pit viper species found in central Mexico.

[5] Adults usually grow to a total length of 60 to 70 cm (24 to 28 in), although exceptionally large specimens may be as much as 100 cm (39 in) long.

[3] The species is found on the plateau of central Mexico from southern Zacatecas and northeastern Colima east to east-central Veracruz.

The type locality given is "Table Land, Mexico", although a restriction to "Tupátaro, Guanajuanto, Mexico" was proposed by H.M. Smith and Taylor (1950).

[1] 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.