Sistrurus ravus

Sistrurus ravus
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Vertebrata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Viperidae
Subfamily:	Crotalinae
Genus:	Sistrurus
Species:	S. ravus
Binomial name
Sistrurus ravus (Cope, 1865)
Synonyms
Crotalus ravus - Cope, 1865 Caudisona rava - Cope, 1875 [Crotalus miliarius] Var. ravus - Garman, 1884 Crotalophorus ravus - Cope, 1885 Sistrurus ravus - Boulenger, 1896 Crotalus (Sistrurus) ravus - Hoge, 1966 Sistrurus ravus ravus - Harris & Simmons, 1977 Sistrurus ravus lutescens - Harris & Simmons, 1977[1]

Common names: Mexican pigmy rattlesnake,^[2] Mexican pygmy rattlesnake,^[3] more.

Sistrurus ravus is a venomous pitviper species, found only in Mexico. Three subspecies are currently recognized, including the nominate subspecies described here.^[4]

Description

Adults of this species usually grow to a length of 40-65 cm, but may reach more than 70 cm. They are moderately stout in build.^[3]

The distinguishing characteristics for S. r. ravus include parietal scales that are highly variable in shape, less than 3 prefoveals, 21 midbody dorsal scales, 2-4 tail bands and a relatively large rattle.^[3]

Common names

Mexican pigmy rattlesnake,^[2] Mexican pygmy rattlesnake.^[3] Local names are víbora-cascabel pigmea-mexicana (Spanish),^[4] colcóatl, cascabel enana, víbora de cascabel and viborita de cascabel.^[3]

Geographic range

Found only in Mexico in the mountains in the center and south of the country, west of the Isthmus of Tehuantepec. Its range includes the southeastern part of the Mexican Plateau in the highlands of Mexico, Morelos, Tlaxcala, Puebla, Veracruz, Oaxaca and the Sierra Madre del Sur in Guerrero. The type locality given is the "Table land of Mexico." Cochran (1961) interpreted this to be the "south tableland, Veracruz, Mexico."^[1]

Campbell and Lamar (2004) describe this species as being found across the Mexican Plateau in the temperate regions of moderate to high elevations. They estimate the vertical distribution to be from about 1,490 m above sea level to a little over 3,000 m altitude.^[3]

Subspecies

Subspecies[4]	Taxon author[4]	Common name[5]	Geographic range[3]
S. r. brunneus	Harris & Simmons, 1977	Oaxacan pigmy rattlesnake	Mexico in the highlands of Oaxaca.
S. r. exiguus	Campbell & Armstrong, 1979	Guerreran pigmy rattlesnake	Mexico in the Sierra Madre del Sur of central Guerrero.
S. r. ravus	(Cope, 1865)	Central Mexican pigmy rattlesnake	Mexico in the Altiplanicie Meridional, including the states of México, Morelos, Tlaxcala, Puebla and Veracruz.

See also

• List of crotaline species and subspecies
• Crotalinae by common name
• Crotalinae by taxonomic synonyms
• Snakebite

References

1. ^ ^{a b} McDiarmid RW, Campbell JA, Touré T. 1999. Snake Species of the World: A Taxonomic and Geographic Reference, vol. 1. Herpetologists' League. 511 pp. ISBN 1-893777-00-6 (series). ISBN 1-893777-01-4 (volume).
2. ^ ^{a b} Klauber LM. 1997. Rattlesnakes: Their Habitats, Life Histories, and Influence on Mankind. Second Edition. 2 volumes. Reprint, University of California Press, Berkeley. ISBN 0-520-21056-5.
3. ^ ^{a b c d e f g} Campbell JA, Lamar WW. 2004. The Venomous Reptiles of the Western Hemisphere. Comstock Publishing Associates, Ithaca and London. 870 pp. 1500 plates. ISBN 0-8014-4141-2.
4. ^ ^{a b c d} "Sistrurus ravus". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=586091. Retrieved 4 March 2007. 
5. ^ Sistrurus ravus at the Reptarium.cz Reptile Database. Accessed 12 December 2007.