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Echis carinatus. © Peter Uetz |
Order Squamata
Superfamily Xenophidia (Colubroidea Caenophidia)
Members of this family are the best-known venomous snakes.The most familiar viperids in America are the rattlesnakes (genera Crotalus and Sistrurus).
Echis carinatus. © Peter Uetz
Appearance: Viperids typically have broad, triangular heads. Most are also heavy-bodied with relatively short, stender tails. Most vipers have numerous and heavily keeled body scales. Their long fangs permit deep penetration and envenomation of prey. The hinged-fang mechanism allows their storage against the roof of the mouth when not in use. The structure of the hinge mechanism is unique; the lateral process of the palatine bone is absent, each maxilla is cuboidal and bears a single enlarged maxillary tooth (several replacement fangs lie behind the functional fang), the maxillary fang has a duct on its anterior face, and the elongate ectopterygoid serves as a lever to erect or depress the fang. The pit-organs of the crotalines lie on each side of the head between the nostril and eye and contain infrared receptors. They allow the snake to detect prey whose body temperature differs from background temperatures
Distribution: They occur on all continents except Australia.
Habitat: As indicated by their wide distribution, vipers can be found in most ecological habitats from tropical rain forests to deserts and even high mountains. Crotalines contain arboreal (e.g. Trimeresurus), terrestrial (e.g. Crotalus), and aquatic secies. Viperines are usually terrestrial, although some burrow in desert sands (e.g. Cerastes, Echis) or are arboreal (Atheris).
Size: Small to large (Bitis schneideri, max. 28 cm total length; Lachesis muta, up to 3.6 m).
Food: Small mammals, birds, other vertebrates.
Behaviour: mostly nocturnal, when they can rely on their pit organs as opposed to visual cues for detecting prey. The pit organs are special organs for the detection of infrared radiation ("heat"). The only other snake family with infrared detection are the boids.
Reproduction: Most crotalines are live-bearers (among the few exceptions are Calloselasma, some Trimeresurus, and Lachesis, which are oviparous). Possibly ail oviparous crotatines guard their eggs. Viperines include both oviparous (e.g., Causus, Echis coloratus) and ovoviviparous groups (Bitis, Echis carinatus, most Vipera).
Relationships: The Southeast Asian viper Azemiops feae seems to form a separate clade of pitless viper that seems to be closer to the crotalines than to the viperines. Unlike most other vipers, it has colubridlike head scales, smooth body scales, no tracheal lung, and no loreal pit-organs.
Venom: All vipers are venomous. In North America most casualties through snakebite are caused by Crotalus atrox. Species of the genus Echis cause up to 100,000 accidents in Africa and Asia.
Note: The genus Bothrops has been split into the following genera: Bothrops, Bothriechis, Atropoides, Cerrophidion, Ophryacus, and Porthidium. The genus Atheris has been split into the genera Atheris, Montatheris, and Proatheris by Broadley (1996). Malhotra & Thorpe (2004) have proposed a number of new genera (or revalidated some older ones) for various species groups within Ovophis and Trimeresurus, namely Garthius, Cryptelytrops, Parias, Viridovipera, Peltopelor, Popeia, Himalayophis (search database for synonyms = Trimeresurus). It remains to be seen if these new genera will be accepted by the scientific community (see database for specific assignments). Montivipera was suggested as a subgenus of Vipera by Nilsson et al. (1999) and has also been used as a genus for Vipera xanthina.
Consulting expert: Dr. Wolfgang Wüster (School of Biological Sciences, University of Wales, UK)
Subfamily Crotalinae (Pit Vipers)
Himalayophis (tibetanus) = Trimeresurus (karanshahi)
Subfamily Viperinae (Pitless Vipers)
Subfamily Azemiopinae
Click on genus to get a list of species. Use the Search form for more sophisticated searches.
Phylogeny of pitvipers
Bayesian MCMC 50% majority-rule consensus phylogram compiled from analyses of 2306 bp of mitochondrial DNA sequences analyzed under the best-fit “10x" partitioned model. Modified after Castoe et al. (2006).
Brattstrom, Bayard H. (1964)
Evolution of the pit vipers.
Transactions of the San Diego Society of Natural History 13 (11):
185-268
Broadley, D.G. (1996)
A review of the tribe Atherini (Serpentes: Viperidae), with the
descriptions of two new genera.
Afr. J. Herpetology, 45: 40-48.
Campbell, J.A. & Lamar, W.W. (1989)
The Venomous Reptiles of Latin America
Comstock, Ithaca
Castoe, Todd A. and Christopher L. Parkinson (2006)
Bayesian mixed models and the phylogeny of pitvipers
(Viperidae: Serpentes).
Molecular Phylogenetics and Evolution 39 (1): 91-110
Cullings, K.W., Morafka, D.J., Hernandez, J. and Roberts, J.W.
(1997)
Reassessment of phylogenetic relationships among pitviper
genera based on mitochondrial cytochrome b gene sequences.
Copeia, 1997: 429-432.
Golay, P. et al. (1993)
Endoglyphs and other major venomous sankes of the world - a
checklist
Azemiops, Geneva
Gumprecht, A.; Tillack, F.; Orlov, N.L.; Captain, A. &
Ryabow, S. (2004)
Asian pitvipers.
Geitje
Books, Berlin, 368 pp.
Guo, Peng; Pang, Junfeng; Zhang, Yaping; Zhao, Ermi (2006)
A Re-analysis of the phylogeny of the genus Protobothrops (Reptilia: Viperidae), with particular reference to the systematic position of P. xiangchengensis.
Amphibia-Reptilia 27 (3): 433-439
Harding,K.A. & Welch,K.R.G. (1980)
Venomous Snakes of the World - A Checklist
Pergamon Press, (Oxford)
ISBN 0-08-025495-0
Also published as Supplement to the journal Toxicon 1 (1980)
Hoge, A.R. and Romano-Hoge, S.A.R.W.L. (1978/79)
Poisonous snakes of the world. Part I. Checklist of the pit
vipers, Viperoidea, Viperidae, Crotalinae.
Mem. Inst. Butantan 42/43, 179-310.
Joger,U. (1983)
Book review of Harding & Welch's Checklist (contains
many corrections)
Salamandra 19 (3): 99-102
Klauber, Laurence M. (1972)
Rattlesnakes: Their Habits, Life Histories, and Influence on
Mankind.
University of California Press, Berkeley, CA, vol. 1: xxx +
740; vol. 2: xvii + 795 pp. [first published 1956]
Kraus, F., Mink, D.G. and Brown, W.M. (1996)
Crotaline intergeneric relationships based on mitochondrial DNA
sequence data.
Copeia, 1996: 763-773.
Malhotra, Anita & Thorpe, Roger S. (2004)
A phylogeny of four mitochondrial gene regions suggests a
revised taxonomy for Asian pitvipers (Trimeresurus and
Ovophis).
Molecular Phylogenetics and Evolution 32: 83
&endash;100
Nilson,G., Andren,C. & Flärdh,B. (1988)
Die Vipern der Türkei
Salamandra 24 (4): 215-247
Nilson,G.; TUNIYEV,B.; ANDRÉN,C.; ORLOV,N.; JOGER,U.
& HERRMANN,H. W. 1999.
Taxonomic position of the Vipera xanthina complex.
Kaupia (Darmstadt) (8): 99-102
Parkinson, C.L., Moody, S.M. and Ahlquist, J.E. (1997)
Phylogenetic relationships of the 'Agkistrodon complex' based
on mitochondrial DNA sequence data. In: Venomous Snakes:
Ecology, Evolution and Snakebite, pp. 63-78. (Thorpe, R.S.,
Wüster, W. and Malhotra, A. Eds).
Symposia of the Zoological Society of London, No. 70. Oxford:
Clarendon Press.
Vidal, N., Lecointre, G., Vié, J.C. and Gasc, J.P.
(1997)
Molecular systematics of pitvipers: paraphyly of the Bothrops complex.
C.R. Acad. Sci. Paris, Sci. Vie, 320: 95-101.
Vidal, N., Lecointre, G., Vié, J.C. and Gasc, J.P.
(1999)
What can mitochondrial gene sequences tell us about
intergeneric relationships of pitvipers?
Kaupia (Darmstadt) (8): 107-112
Werman,S.D. (1999)
Molecular phylogenetics and morphological evolution in
neotropical pitvipers: an evaluation of mitochondrial DNA sequence
information and the comparative morphology of the cranium and
palatomaxillary arch.
Kaupia (Darmstadt) (8): 113-126
Ziegler, T., H. W. Herrmann, P. David, N. Orlov & O. S. G.
Pauwels (2000)
Triceratolepis sieversorum, a new genus and species of pitviper
(Reptilia: Serpentes: Viperidae: Crotalinae) from Vietnam.
Russ. J. Herpetol. 7 (3): 199-214
Zug,G.R.; Vitt, L.J. & Caldwell, J.P. (2001)
Herpetology,
2nd ed.
Academic Press San Diego, London, [...]XIV + 630 pp.
Online Information:
Created: 26 Jan 1996 / Last changed: 8 May 2008