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Crotalus simus

Crotalus simus
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Viperidae
Subfamily: Crotalinae
Genus: Crotalus
Species: C. simus
Binomial name
Crotalus simus
Latreille In Sonnini & Latreille, 1801
  • Crotalus simus - Latreille In Sonnini & Latreille, 1801
  • Caudisona durissa - Cope, 1861
  • C[rotalus]. terrificus - Cope In Yarrow In Wheeler, 1875
  • Crotalus durissus durissus - Klauber, 1936
  • C[rotalus] terrificus copeanus - Amaral, 1937
  • Crotalus (Crotalus) durissus durissus - Peters & Orejas-Miranda, 1970
  • Crotalus durissus neoleonensis - Juliá-Zertuche & Treviño-Saldaña, 1978 (nomen nudum)[1][2]
Common names: Middle American rattlesnake,[1] Central American rattlesnake.[3]

Crotalus simus is a venomous pitviper species found in Mexico and Central America. The specific epithet is Latin for "flat nosed"; likely an allusion to the fact that its head is relatively blunt when compared with the lanceheads (Bothrops). Currently, 3 subspecies are recognized, including the nominate subspecies described here.[4]

Additional recommended knowledge



Adults commonly exceed 130 cm in length, with males growing larger than females. Large males reach 140-160cm in some populations. The maximum reported length is 180 cm.[1]

The body has an exceedingly rough appearance as the normal dorsal scale keels are accentuated into protuberances or tuberculations. This is most apparent on the scale rows to either side of the vertebral scales, with a decreasing intensity in the lower rows. The vertebral scales are about as prominently keeled as the fourth row down on the flanks (with the vertebral scales as the first row).[3]

Geographic range

Found from Mexico in southwestern Michoacán on the Pacific coast, and Veracruz and the Yucatan Peninsula on the Atlantic coast, south through Belize, Guatemala, El Salvador, Honduras and Nicaragua to west-central Costa Rica. It is absent from Panama, but apparently does occur on the Atlantic side of Colombia.[1] The type locality given is "Ceylan," which is incorrect.[2]


Usually found in regions that are semiarid, including tropical forests that are dry or very dry, thorn woodland and arid scrub forest. It also occurs in mesic forests with relatively dry open areas.[1]


Bites from this species are similar to rattlesnake bites in the United States. Local symptoms may be severe, with pain, massive swelling, blistering and necrosis that often lead to physicians performing fasciotomies and in some cases amputations. Systemic effects involving hemostatic disturbances are rare, as are renal failure and neurotoxicity. Only venom from neonates contains crotoxin; a constituent typically found in C. durissus venom that produces to neurotoxic symptoms.[5]


Subspecies[4] Authority[4] Common name[3] Geographic range[3]
C. s. culminatus Klauber, 1952 Northwestern neotropical rattlesnake Mexico in southwestern Michoacán, southern and western Morelos, Guerrero and southwestern Oaxaca. It probably also occurs in extreme western Puebla and possibly in the Mexican Federal District.
C. s. simus Latreille In Sonnini & Latreille, 1801 Central American rattlesnake Southeastern Mexico (central Veracruz, southeastern Oaxaca, Tabasco and Chiapas), central and southern Guatemala, western and southern Honduras, southern Belize, El Salvador, southwestern Nicaragua, and northwestern and central Costa Rica.
C. s. tzabcan Klauber, 1952 Yucatán neotropical rattlesnake Mexico (Yucatán, Campeche, Quintana Roo and eastern Tabasco), northern Guatemala and northern Belize.


Previously, the description for this form was listed as the nominate subspecies for the tropical rattlesnake, C. durissus.[2]

See also


  1. ^ a b c d e Campbell JA, Lamar WW. 2004. The Venomous Reptiles of the Western Hemisphere. 2 volumes. Comstock Publishing Associates, Ithaca and London. 870 pp. 1500 plates. ISBN 0-8014-4141-2.
  2. ^ a b c 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 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.
  4. ^ a b c Crotalus simus (TSN 727493). Integrated Taxonomic Information System. Accessed on 28 August 2007.
  5. ^ 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.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Crotalus_simus". A list of authors is available in Wikipedia.
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