{{Short description|Subfamily of snakes}}{{More citations needed|date=June 2011}}{{Use dmy dates|date=September 2020}}{{Automatic taxobox|Agkistrodon|Palisot de Beauvois, 1799|Atropoides|Werman, 1992|Bothrocophias|Calloselasma|Cerrophidion|Campbell & Lamar, 1992|Craspedocephalus|Gloydius|Hoge & Romano-Hoge, 1981|Hypnale|Mixcoatlus|Jadin, H.M.Smith & Campbell, 2011|Porthidium|Protobothrops|Hoge & Romano-Hoge, 1983 |Tropidolaemus

Early Miocene\|present}}\| image = Timber Rattlesnake by Trisha.jpg\| image_caption = Timber rattlesnake (Crotalus horridus), showing the characteristic infrared pit below and between the eye and nostril\| taxon = Crotalinae	Nicolaus Michael Oppel>Oppel, 1811\| synonyms = * Crotalini Oppel, 1811 Crotales Cuvier, 1817 Crotalidae Gay, 1825 Crotaloidae Fitzinger, 1826 Cophiadae Boie, 1827 Crotaloidei Eichwald, 1831 Crotalina Bonaparte, 1831 Bothrophes Fitzinger, 1843 Crotalinae Cope, 1860 Teleuraspides Cope, 1871 Crotalida Strauch, 1873 Bothrophera Garman, 1884 Cophiinae Cope, 1895 Lachesinae Cope, 1900 Lachesinii Smith, Smith & Sawin, 1977 Agkistrodontinii Hoge & Romano-Hoge, 1981 Agkistrodontini Hoge & Romano-Hoge, 1983(:fr:Roy Wallace McDiarmid\|McDiarmid RW), Campbell JA, TourÃ© T (1999). Snake Species of the World: A Taxonomic and Geographic Reference, Volume 1. Washington, District of Columbia: Herpetologists’ League. 511 pp. {{ISBN\|1-893777-00-6}} (series). {{ISBN\|1-893777-01-4}} (volume). }}The Crotalinae, commonly known as pit vipers,Mehrtens JM (1987). Living Snakes of the World in Color. New York: Sterling Publishers. 480 pp. {{ISBN\|0-8069-6460-X}}.Sometimes spelled “pitvipers” â€“ Campbell & Lamar, 2004 {{Page needed\|date=June 2011}} or pit adders, are a subfamily of vipers found in Asia and the Americas. Like all other vipers, they are venomous. They are distinguished by the presence of a heat-sensing pit organ located between the eye and the nostril on both sides of the head. Currently, 23 genera and 155 species are recognized:{{ITIS \|id=634394 \|taxon=Crotalinae \|access-date=26 October 2006}} These are also the only viperids found in the Americas. The groups of snakes represented here include rattlesnakes, lanceheads, and Asian pit vipers. The type genus for this subfamily is Crotalus, of which the type species is the timber rattlesnake, C. horridus.{{Citation needed\|date=June 2011}}These snakes range in size from the diminutive hump-nosed viper, Hypnale hypnale, that grows to a typical total length (including tail) of only {{convert\|30\|-\|45\|cm\|in\|abbr=on}}, to the bushmaster, Lachesis muta, a species known to reach a maximum total length of {{convert\|3.65\|m\|ft\|abbr=on}} in length.This subfamily is unique in that all member species share a common characteristic â€“ a deep pit, or fossa, in the loreal area between the eye and the nostril on either side of the head. These loreal pits are the external openings to a pair of extremely sensitive infrared-detecting organs, which in effect give the snakes a sixth sense to help them find and perhaps even judge the size of the small, warm-blooded prey on which they feed.Campbell JA, Lamar WW (2004). The Venomous Reptiles of the Western Hemisphere. Ithaca and London: Comstock Publishing Associates. 870 pp., 1,500 plates. {{ISBN\|0-8014-4141-2}}. The pit organ is complex in structure and is similar to the thermoreceptive labial pits found in boas and pythons. It is deep and located in a maxillary cavity. The membrane is like an eardrum that divides the pit into two sections of unequal size, with the larger of the two facing forwards and exposed to the environment. The two sections are connected via a narrow tube, or duct, that can be opened or closed by a group of surrounding muscles. By controlling this tube, the snake can balance the air pressure on either side of the membrane. The membrane has many nerve endings packed with mitochondria. Succinic dehydrogenase, lactic dehydrogenase, adenosine triphosphate, monoamine oxidase, generalized esterases, and acetylcholine esterase have also been found in it. When prey comes into range, infrared radiation falling onto the membrane allows the snake to determine its direction. Having one of these organs on either side of the head produces a stereo effect that indicates distance, as well as direction. Experiments have shown, when deprived of their senses of sight and smell, these snakes can strike accurately at moving objects less than {{convert\|0.2\|C-change\|F-change}} warmer than the background.Parker HW, Grandison AGC. 1977. Snakes -- a natural history. Second Edition. British Museum (Natural History) and Cornell University Press. 108 pp. 16 plates. LCCCN 76-54625. {{ISBN\|0-8014-1095-9}} (cloth), {{ISBN\|0-8014-9164-9}} (paper). The paired pit organs provide the snake with thermal rangefinder capabilities.Bullock, T. H. and Diecke, F. P. J. (1956). Properties of an infrared receptor. Journal of Physiology 134, 47-87. Clearly, these organs are of great value to a predator that hunts at night, as well as for avoiding the snake’s own predators.Stidworthy J. 1974. Snakes of the World. Grosset & Dunlap Inc. 160 pp. {{ISBN\|0-448-11856-4}}.Among vipers, these snakes are also unique in that they have a specialized muscle, called the muscularis pterigoidius glandulae, between the venom gland and the head of the ectopterygoid. Contraction of this muscle, together with that of the muscularis compressor glandulae, forces venom out of the gland. Evolution The earliest known fossil pit viper remains are from the Early Miocene of Nebraska. As pit vipers are thought to have had an Asian origin before eventually colonizing the Americas, this suggests that they must have originated and diversified even earlier. During the Late Miocene, they reached as far west as eastern Europe, where they are no longer found; it is thought that they did not expand further into Europe.WEB, The first European pit viper from the Miocene of Ukraine - Acta Palaeontologica Polonica,www.app.pan.pl/article/item/app44-327.html, 2024-02-21, www.app.pan.pl, Geographic range The subfamily Crotalinae is found from Central Asia eastward and southward to Japan, China, Indonesia, peninsular India, Nepal, and Sri Lanka. In the Americas, they range from southern Canada southward to Central America to southern South America. Habitat Crotalines are a versatile subfamily, with members found in habitats ranging from parched desert (e.g., the sidewinder, Crotalus cerastes) to rainforests (e.g., the bushmaster, Lachesis muta). They may be either arboreal or terrestrial, and at least one species (the cottonmouth, Agkistrodon piscivorus) is semiaquatic. The altitude record is held jointly by Crotalus triseriatus in Mexico and Gloydius strauchi in China, both of which have been found above the treeline at over 4,000 m above sea level. Behavior Although a few species of crotalines are highly active by day, such as Trimeresurus trigonocephalus, a bright green pit viper endemic to Sri Lanka, most are nocturnal, preferring to avoid high daytime temperatures and to hunt when their favored prey are also active. The snakes’ heat-sensitive pits are also thought to aid in locating cooler areas in which to rest.JOURNAL, Krochmal, Aaron R., Bakken, George S., Thermoregulation is the pits: use of thermal radiation for retreat site selection by rattlesnakes, Journal of Experimental Biology, 1 August 2003, 206, 15, 2539â€“2545, 10.1242/jeb.00471, 12819261, 18140029,journals.biologists.com/jeb/article/206/15/2539/20239/Thermoregulation-is-the-pits-use-of-thermal, 11 June 2022, As ambush predators, crotalines typically wait patiently somewhere for unsuspecting prey to wander by. At least one species, the arboreal Gloydius shedaoensis of China, is known to select a specific ambush site and return to it every year in time for the spring migration of birds. Studies have indicated these snakes learn to improve their strike accuracy over time.Shine R, Sun L, Kearney M, Fitzgerald M (2002). “Why do Juvenile Chinese Pit-Vipers (Gloydius shedoaensis) Select Arboreal Ambush Sites?” Ethology 108: 897â€“910. ISSN 0179-1613. PDF {{webarchive\|url=https://web.archive.org/web/20080724094745www.bio.usyd.edu.au/Shinelab/old%20labbers/mark/349whydojuvenile.pdf \|date=24 July 2008 }} at University of Sydney School of Biological Sciences. Accessed 26 October 2006.Many temperate species of pit vipers (e.g. most rattlesnakes) congregate in sheltered areas or “dens” to overwinter (brumate, see hibernation), the snakes benefiting from the combined heat. In cool temperatures and while pregnant, pit vipers also bask on sunny ledges. Some species do not mass together in this way, for example the copperhead, Agkistrodon contortrix, or the Mojave rattlesnake, Crotalus scutulatus.{{Citation needed\|date=June 2011}}Like most snakes, crotalines keep to themselves and strike only if cornered or threatened. Smaller snakes are less likely to stand their ground than larger specimens. Pollution and the destruction of rainforests have caused many pit viper populations to decline. Humans also threaten pit vipers, as many are hunted for their skins or killed by cars when they wander onto roads.{{Citation needed\|date=June 2011}} Reproduction With few exceptions, crotalines are ovoviviparous, meaning that the embryos develop within eggs that remain inside the mother’s body until the offspring are ready to hatch, when the hatchlings emerge as functionally free-living young. In such species, the eggshells are reduced to soft membranes that the young shed, either within the reproductive tract, or immediately after emerging.Among the oviparous (egg-laying) pit vipers are Lachesis, Calloselasma, and some Trimeresurus species. All egg-laying crotalines are believed to guard their eggs.{{Citation needed\|date=June 2011}}Brood sizes range from two for very small species, to as many as 86 for the fer-de-lance, Bothrops atrox, which is among the most prolific of all live-bearing snakes.Many young crotalines have brightly coloured tails that contrast dramatically with the rest of their bodies. These tails are known to be used by a number of species in a behavior known as caudal luring; the young snakes make worm-like movements with their tails to lure unsuspecting prey within striking distance. JOURNAL, Heatwole, H., Elizabeth, Davison, 1976, A Review of Caudal Luring in Snakes with Notes on Its Occurrence in the Saharan Sand Viper, Cerastes vipera, Herpetologica, 32, 3, 332â€“336	access-date=2021-08-24,www.jstor.org/stable/3891463, Taxonomy In the past, the pit vipers were usually classed as a separate family: the Crotalidae. Today, however, the monophyly of the viperines and the crotalines as a whole is undisputed, which is why they are treated here as a subfamily of the Viperidae.{{Citation needed\|date=June 2011}} Genera{\|class“wikitable” ! Genus{{ITIS \|id=634394 \|taxon=Crotalinae \|access-date=26 October 2006}}! Taxon author! Species! Common name! Geographic rangeMcDiarmid RW, Campbell JA, TourÃ© 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).
Moccasins	North America from the northeastern and central USA southward through peninsular Florida and southwestern Texas. In Central America on the Atlantic versant from Tamaulipas and Nuevo LeÃ³n southward to the YucatÃ¡n Peninsula, Belize and Guatemala. Along the Pacific coastal plain and lower foothills from Sonora south through Guatemala, El Salvador, Honduras and Nicaragua to northwestern Costa Rica.
Bothriechis	Wilhelm Peters>Peters, 1859	Oaxaca and the northern highlands of Chiapas), through Central America to northern South America (Colombia, western Venezuela, Ecuador and northern Peru
Ronald L. Gutberlet Jr.>Gutberlet & Campbell, 2001	Bothrops	Johann Georg Wagler>Wagler, 1824	Argentina; Saint Lucia and Martinique in the Lesser Antilles; Ilha da Queimada Grande off the coast of Brazil
Edward Drinker Cope>Cope, 1860	Thailand to northern Malaysia and Java, Indonesia
Guerrero and southeastern Oaxaca), southward through the highlands of Central America (Guatemala, El Salvador, Honduras, northern Nicaragua, Costa Rica) to western Panama
Heinrich Kuhl> Kuhl & van Hasselt, 1822	Pit viper	India to Thailand to northern Malaysia and Indonesia
Crotalus{{sup>T}}	Carl Linnaeus>Linnaeus, 1758	Deinagkistrodon	Howard K. Gloyd>Gloyd, 1979	Garthius\|Malhotra & Thorpe, 2004	Borneo
Ural Mountains through Siberia, Iran, the Himalayas from Pakistan, India, Nepal and China, Korea, Japan and the Ryukyu Islands
Leopold Fitzinger>Fitzinger, 1843	Sri Lanka and India
Lachesis (genus)>Lachesis	FranÃ§ois Marie Daudin>Daudin, 1803	Metlapilcoatlus\|Campbell, Frost, & Castoe, 2019	Panama. On the Pacific versant, they occur in isolated populations in east-central and southern Mexico, Guatemala, El Salvador, Costa Rica, and Panama.
Ophryacus	Edward Drinker Cope>Cope, 1887	Ovophis\|Burger, 1981	Seven Sister States>Seven Sisters (Assam) of India eastward through Myanmar, Cambodia, Thailand, Laos, Vietnam, West Malaysia, Taiwan, Japan (Okinawa) and Indonesia (Sumatra)
Edward Drinker Cope>Cope, 1871	Colima, Oaxaca and Chiapas on the Pacific side, the YucatÃ¡n Peninsula on the Atlantic side) southward through Central America to northern South America (Ecuador in the Pacific lowlands, northern Venezuela in the Atlantic lowlands)
Sistrurus	Samuel Garman>Garman, 1883	Trimeresurus	Bernard Germain de LacÃ©pÃ¨de>LacÃ©pÃ¨de, 1804	Malay Archipelago to Timor
Johann Georg Wagler>Wagler, 1830	Type genus.{{Reflist\|group=ref}} See also List of crotaline species and subspecies References {{Reflist\|2}} Further reading Gumprecht, Andreas; Tillack, Frank (2004). “A proposal for a replacement name of the snake genus Ermia Zhang, 1993”. Russian Journal of Herpetology 11: 73â€“76. Wright, Albert Hazen; Wright, Anna Allen (1957). Handbook of Snakes of the United States and Canada. Ithaca and London: Comstock Publishing Associates, a Division of Cornell University Press. 1,105 pp. (in two volumes). (Seventh Printing 1985). (“Crotalidae”, p. 901). Goris RC (2011). “Infrared organs of snakes: an integral part of vision”. Journal of Herpetology 45: 2â€“14. External links {{Commons category\|Crotalinae}}{{Wikispecies\|Crotalinae}} Pit organs at Life is Short, but Snakes are Long {{Taxonbar\|from=Q595983}}{{Authority control}} - content above as imported from Wikipedia - "pit viper" does not exist on GetWiki (yet) - time: 6:17am EDT - Wed, May 22 2024 [ this remote article is provided by Wikipedia ] LATEST EDITS [ see all ] GETWIKI 21 MAY 2024 The Illusion of Choice Culture GETWIKI 09 JUL 2019 Eastern Philosophy History of Philosophy GETWIKI 09 MAY 2016 GetMeta:About GetWiki GETWIKI 18 OCT 2015 M.R.M. Parrott Biographies GETWIKI 20 AUG 2014 GetMeta:News GetWiki ABOUT CONTACT MRMPARROTT.COM RIMRIC.COM CONNECT [GetWiki] © 2024 M.R.M. PARROTT \| ALL RIGHTS RESERVED

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pit viper

Evolution

Geographic range

Habitat

Behavior

Reproduction

Taxonomy

Genera{|class“wikitable”

See also

References

Further reading

External links