Crotalus lorenzoensis is a species of pit viper.
These vipers are usually smaller than their counterparts on the mainland.
C. lorenzoensis is only known from the type locality, which is San Lorenzo Island, thus making it an endemic species.
The snakes live mainly in rocky areas and arroyo bottoms, sometimes in dunes near the coast and in cavities formed by adjacent boulders.
This species is classified as "Least Concern" (LC) on the IUCN Red List of Threatened Species.