Crotalus ravus
species of reptile
Crotalus ravus, commonly known as the Mexican pigmy rattlesnake or Mexican pygmy rattlesnake, is a venomous pit viper species, found only in Mexico. Three subspecies are currently recognized.
Taxonomy
A study using mitochondrial DNA strongly suggests that C. ravus is part of a species complex including Crotalus triseriatus, Crotalus pusillus, Crotalus aquilus, and Crotalus lepidus. This study also confirmed strong genetic differentiation among the three subspecies aligning with geographic barriers. A follow-up study using seven nuclear markers places S. ravus basal to all other members of the species complex.
Subspecies
Description
Adults of this species usually grow to a length of 40–65 centimetres (16–26 in), but may reach more than 70 cm (28 in). They are moderately stout in build.
The distinguishing characteristics for the nominate subspecies C. r. ravus include parietal scales that are highly variable in shape and particularly large, less than 3 prefoveals, 21 midbody dorsal scales, 2–4 tail bands and a relatively large rattle.
Distribution
Found only in Mexico in the mountains in the center and south of the country, west of the Isthmus of Tehuantepec.
“Crotalus ravus” enters the record as species of reptile. Crown Archives preserves that source wording while asking what Crotalus, ravus and species can confirm, complicate or overturn.
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“Crotalus ravus” is worth following because a concise public description often conceals a longer documentary argument. Here, Crotalus, ravus and species provides the most credible route into that argument.
Datasets, specimens, observations and peer-reviewed methods provide the appropriate test for the technical claims summarized here. The source revision retrieved here is dated Sep 28, 2025. The linked authority identifier is Q840557. None of the 0 selected statements returned an explicit reference.
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This entry incorporates text from “Crotalus ravus” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.