Crotalus durissus

Crotalus durissus
Venezuelan rattlesnake, C. d. cumanensis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Vertebrata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Viperidae
Subfamily:	Crotalinae
Genus:	Crotalus
Species:	C. durissus
Binomial name
Crotalus durissus Linnaeus, 1758
Synonyms
Crotalus Dryinas Linnaeus, 1758 [Crotalus] Durissus Linnaeus, 1758 Caudisona orientalis Laurenti, 1768 Caudisona Gronovii Laurenti, 1768 Crotalus orientalis - Gmelin, 1788 Crotalus strepitans var. dryinas - Daudin, 1803 [Urocrotalon] durissus - Fitzinger, 1843 Uropsophus durissus - Gray, 1849 Crotalus durissus - Boulenger, 1896 Crotalus pulvis Ditmars, 1905 [Crotalus] terrificus durissus - Amaral, 1929 Crotalus terrificus durissus - Amaral, 1929 [Crotalus] Gronovii - Klauber, 1936 Crotalus durissus dryinus - Hoge, 1966 Crotalus (Crotalus) durissus dryinus - Peters & Orejas-Miranda, 1970[1][2]

Common names: South American rattlesnake,^[1] tropical rattlesnake,^[3] more.

Crotalus durissus is a venomous pitviper species found in South America. The most widely distributed member of its genus,^[1] this species poses a serious medical problem in many parts of its range.^[4] Currently, 9 subspecies are recognized, including the nominate subspecies described here.^[5]

Description

Grows to a maximum length of about 180 cm (about 6 feet).^[1]

Common names

South American rattlesnake,^[1] tropical rattlesnake,^[3] neotropical rattlesnake,^[6] Guiana rattlesnake (previously used for C. d. dryinus).^[7]

Spanish: víbora de cascabel, cascabel, cascabela, cascavel.^[1]

Geographic range

Found in all South American countries except Ecuador and Chile. However, its range is discontinuous,^[1] with many isolated populations in northern South America, including Colombia, Venezuela, Guyana, Suriname, French Guiana and northern Brazil. It occurs in Colombia and eastern Brazil to southeastern Peru, Bolivia, Paraguay, Uruguay, and northern Argentina (Catamarca, Córdoba, Corrientes, Chaco, Entre Rios, Formosa, La Pampa, La Rioja, Mendoza, Misiones, San Juan, San Luis, Santa Fe, Santiago del Estero and Tucumán).^[2] Also occurs on some islands in the Caribbean, including Morro de la Iguana, Tamarindo and Aruba.^[1] The type locality given is "America."^[2]

Habitat

Prefers savanna, caatinga and cerrado. It has been reported to occur in littoral xerophilous scrub, psammophilous and halophilous littoral grassland thorny xerophilous scrub, tropophilous deciduous and semidesciduous scrub, as well as tropophilous semidesciduous seasonal forest in the northwest of Venezuela. In the Chaco region of Paraguay, it is said to prefer the drier, sandier areas (Böckeler, 1988).^[1]

Venom

C. d. terrificus in Avaré, São Paulo, Brazil.

Bite symptoms are very different from those of Nearctic species^[8] due to the presence of neurotoxins (crotoxin and crotamine) that cause progressive paralysis.^[4] Bites from C. d. terrificus in particular can result in impaired vision or complete blindness, auditory disorders, ptosis, paralysis of the peripheral muscles, especially of the neck, which becomes so limp as to appear broken, and eventually life-threatening respiratory paralysis. The ocular disturbances, which according to Alvaro (1939) occur in some 60% of terrificus cases, are sometimes followed by permanent blindness.^[8] Phospholipase A₂ neurotoxins also cause damage to skeletal muscles and possibly the heart, causing general aches, pain and tenderness throughout the body. Myoglobin released into the blood results in dark urine. Other serious complications may result from systemic disorders (incoagulable blood and general spontaneous bleeding), hypotension and shock.^[4] Hemorrhagins may be present in the venom, but any corresponding effects are completely overshadowed by the startling and serious neurotoxic symptoms.^[8]

Taxonomy

The Guiana rattlesnake, previously recognized as C. d. dryinus,^[2] is now considered a synonym for C. d. durissus. In fact, after the previous nominate subspecies for the durissus complex became the current nominate for C. simus, which now represents its Mexican and Central American members, C. d. dryinus became the new nominate for the South American rattlesnakes as represented by C. durissus.^[1] The subspecies previously known as C. d. collilineatus and C. d. cascavella were moved to the synonymy of C. d. terrificus following the publication of a paper by Wüster et al. in 2005.

Subspecies

Subspecies[ref 1]	Taxon author[ref 1]	Common name	Geographic range
C. d. cumanensis	Humboldt, 1833	Venezuelan rattlesnake[ref 2]	Dry lowlands of Venezuela and Colombia
C. d. durissus	Linnaeus, 1758	South American rattlesnake[ref 3]	Coastal savannas of Guyana, French Guyana and Suriname
C. d. marajoensis	Hoge, 1966	Marajon rattlesnake[ref 4]	Known only from Marajo Island, Para State, Brazil
C. d. maricelae	García Pérez, 1995		Bolson arido de Lagunillas, Estado Merida, Venezuela
C. d. ruruima	Hoge, 1966		Known from the slopes of Mount Roraima and Mount Cariman-Perú in Venezuela (Bolívar). A few specimens have been recorded in Brazil (Roraima).[ref 3]
C. d. terrificus	(Laurenti, 1768)	Cascavel[ref 2]	Brazil south of the Amazonian forests, extreme southeastern Peru, Bolivia, Paraguay, Uruguay, northern Argentina
C. d. trigonicus	Harris & Simmons, 1978		Inland savannas of Guyana
C. d. unicolor	Lidth de Jeude, 1887	Aruba Island rattlesnake[ref 5]	Aruba Island, off the coast of Venezuela.[ref 5]
C. d. vegrandis	Klauber, 1941	Uracoan rattlesnake[ref 5]	Venezuela in Monagas.[ref 5]

1. ^ ^{a b} "Crotalinae". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=634394. Retrieved 26 October 2006. 
2. ^ ^{a b} Mehrtens JM. 1987. Living Snakes of the World in Color. New York: Sterling Publishers. 480 pp. ISBN 0-8069-6460-X.
3. ^ ^{a b} 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. ^ Brown JH. 1973. Toxicology and Pharmacology of Venoms from Poisonous Snakes. Springfield, Illinois: Charles C. Thomas. 184 pp. LCCCN 73-229. ISBN 0-398-02808-7.
5. ^ ^{a b c d} 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.

See also

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

References

1. ^ ^{a b c d e f g h i j} 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.
2. ^ ^{a b c d} 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).
3. ^ ^{a b} Mehrtens JM. 1987. Living Snakes of the World in Color. New York: Sterling Publishers. 480 pp. ISBN 0-8069-6460-X.
4. ^ ^{a b c} Warrell DA. 2004. Snakebites in Central and South America: Epidemiology, Clinical Features, and Clinical Management. In 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.
5. ^ "Crotalus durissus". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=563936. Retrieved 28 November 2007. 
6. ^ U.S. Navy. 1991. Poisonous Snakes of the World. US Govt. New York: Dover Publications Inc. 203 pp. ISBN 0-486-26629-X.
7. ^ Brown JH. 1973. Toxicology and Pharmacology of Venoms from Poisonous Snakes. Springfield, Illinois: Charles C. Thomas. 184 pp. LCCCN 73-229. ISBN 0-398-02808-7.
8. ^ ^{a b c} 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.

Further reading

• Alvaro ME. 1939. Snake Venom in Ophthalmology. Am. Jour. Opth., Vol. 22, No. 10, pp. 1130-1145.
• Wüster W, Ferguson JE, Quijada-Mascareñas JA, Pook CE, Salomão MG, Thorpe RS. 2005. Tracing an invasion: landbridges, refugia and the phylogeography of the Neotropical rattlesnake (Serpentes: Viperidae: Crotalus durissus). Molecular Ecology 14: 1095-1108. PDF at Wolfgang Wüster. Accessed 28 August 2007.
• Wüster W, Ferguson JE, Quijada-Mascareñas JA, Pook CE, Salomão MG, Thorpe RS. 2005. No rattlesnakes in the rainforests: reply to Gosling and Bush. Molecular Ecology, 14: 3619-3621. PDF at Wolfgang Wüster. Accessed 28 August 2007.
• Quijada-Mascareñas A, JE Ferguson, CE Pook, MG Salomão, RS Thorpe, & W Wüster. 2007. Phylogeographic patterns of Trans-Amazonian vicariants and Amazonian biogeography: The Neotropical rattlesnake (Crotalus durissus complex) as an example. Journal of Biogeography 34: 1296–1312.

External links

• Crotalus durissus at the Reptarium.cz Reptile Database. Accessed 19 August 2007.