View source for Azemiops

{{Short description|Genus of snakes}}
{{Automatic taxobox
| image = Azemiops_feae.jpg
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name=IUCN>{{Cite iucn|author=Lau M, Rao D-q|title=''Azemiops feae ''|volume=2012|page=e.T190641A1955758|date=2012|doi=10.2305/IUCN.UK.2012-1.RLTS.T190641A1955758.en}}</ref>
| parent_authority = [[species:Karel Frederik Liem|Liem]], [[species:Hymen Marx|Marx]] & [[species:George Bernard Rabb|Rabb]], 1971
| taxon = Azemiops
| authority = [[George Albert Boulenger|Boulenger]], 1888
|subdivision_ranks=Species
|subdivision=
*''A. feae'' <br /><small>[[George Albert Boulenger|Boulenger]], 1888</small>
*''A. kharini'' <br /><small>[[species:Nikolai Liutsianovich Orlov|Orlov]], [[species:Sergei Aleksandrovich Ryabov|Ryabov]] & [[species:Tao Thien Nguyen|Nguyen]], 2013</small>
}}
'''Azemiopinae''' is a [[monotypic|monogeneric]] subfamily created for the [[genus]] '''''Azemiops''''' that contains the [[Viperidae|viper]] [[species]] ''A. feae'' and ''A. kharini''.<ref>{{cite web|url=http://novataxa.blogspot.com/2013/07/azemiops-kharini.html|title=Species New to Science: [Herpetology • 2013] ''Azemiops kharini'' – White-head Burmese Viper • On the Taxonomy and the Distribution of Snakes of the Genus ''Azemiops'' Boulenger, 1888 (Ophidia: Viperidae: Azemiopinae): Description of a New Species from northeast Vietnam and southeast China|last=Pskhun|date=18 July 2013|website=novataxa.blogspot.com|access-date=11 April 2018}}</ref> They are commonly known as '''Fea's vipers'''.<ref name="Mal03">Mallow D, Ludwig D, Nilson G (2003). ''True Vipers: Natural History and Toxinology of Old World Vipers''. Krieger Publishing Company. 359 pp. {{ISBN|0-89464-877-2}}.</ref> No [[subspecies]] are recognized.<ref name="ITIS">{{ITIS|id=634834|taxon=''Azemiops feae ''|accessdate=23 August 2006}}</ref> The first specimen was collected by [[Italy|Italian]] explorer [[Leonardo Fea]], and was described as a new [[genus]] and new [[species]] by [[George Albert Boulenger|Boulenger]] in 1888.<ref name="Mal03"/> Formerly considered to be one of the most primitive vipers,<ref name="Meh87">Mehrtens JM (1987). ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. {{ISBN|0-8069-6460-X}}.</ref> molecular studies have shown that it is the [[Sister group|sister taxon]] to the pit vipers, [[Pit viper|Crotalinae]].<ref>{{Cite journal|date=2008-11-01|title=A nesting of vipers: Phylogeny and historical biogeography of the Viperidae (Squamata: Serpentes)|journal=Molecular Phylogenetics and Evolution|language=en|volume=49|issue=2|pages=445–459|doi=10.1016/j.ympev.2008.08.019|pmid=18804544|issn=1055-7903|last1=Wüster|first1=Wolfgang|last2=Peppin|first2=Lindsay|last3=Pook|first3=Catharine E|last4=Walker|first4=Daniel E}}</ref><ref>{{Cite journal|date=2016-12-01|title=Diversification in vipers: Phylogenetic relationships, time of divergence and shifts in speciation rates|journal=Molecular Phylogenetics and Evolution|language=en|volume=105|pages=50–62|doi=10.1016/j.ympev.2016.07.029|pmid=27480810|issn=1055-7903|last1=Alencar|first1=Laura RV|last2=Quental|first2=Tiago B|last3=Grazziotin|first3=Felipe G|last4=Alfaro|first4=Michael L|last5=Martins|first5=Marcio|last6=Venzon|first6=Mericien|last7=Zaher|first7=Hussam}}</ref> It is found in the mountains of [[Southeast Asia]],<ref name="USN91">U.S. Navy (1991). ''Poisonous Snakes of the World''. New York: U.S. Government / Dover Publications Inc. 203 pp. {{ISBN|0-486-26629-X}}.</ref> in China, southeastern [[Tibet]], and [[Vietnam]].<ref name="Mal03"/> Like all other vipers, they are [[venomous snake|venomous]].
==Description==
Neither species grows to 1 m in length. According to Liem et al. (1971), the maximum length is 77&nbsp;cm, while Orlov (1997) described a male and a female measuring 72&nbsp;cm and 78&nbsp;cm, respectively.<ref name="Mal03"/>
It is considered to be the most primitive of all viperids for several reasons. It has a reasonably sturdy body and a short tail, but the dorsal scales are smooth rather than [[Keeled scales|keeled]] like those of most vipers. The head, which is slightly flattened and more elliptical in shape than triangular, is not covered with numerous small [[scale (zoology)|scales]] like most other vipers, but with large shields like the [[Colubridae|colubrids]] and the [[Elapidae|elapids]]. Also, the skull is built differently. It does, however, have a pair of hollow, rotating [[fang]]s, although these are short. The fangs have a ridge at the tip lateral to the discharge orifice, as well as a blade-like structure on the ventral surface otherwise seen only in some [[Opisthoglypha|opistoglyphous]] and [[Atractaspididae|atractaspid]] snakes. The venom glands are relatively small. Unlike most vipers, Fea's viper is [[oviparous]] and hibernates during the winter.<ref name="Mal03"/>
The color pattern of Fea's viper is striking; dorsally, its basic body color is a shiny, deep blue-gray to black, marked by several widely spaced, thin (one or two scales), white-orange crossbands. The head is orange to slightly yellow with a distinct cross-pattern outlined in gray. The eyes are yellowish with vertical pupils.<ref name="Mal03"/> Ventrally, it is olive-gray, with some small, lighter spots. The chin and throat are variegated with yellow.
The smooth dorsal scales are arranged in 17 rows at midbody. The anal plate is entire (undivided), but the subcaudals are in two rows (divided). The ventral count is around 180, and subcaudals around 40.
Internasals and prefrontals are subequal in length, which is between 0.7 and 1.0&nbsp;mm. The frontal is slightly broader than long, nearly three times as broad as the supraocular. Parietals are as long as their distance from the end of the snout. The loreal scale is small, pentagonal, and as tall as long. Two (or three) preoculars and two postoculars are present, and two large superposed anterior temporals occur, but only the upper in contact with the postoculars. It has six upper labials. The first and second are smallest, the third enters the eye, and the fourth and fifth are largest. It has seven lower labials, the first is large and forms a suture with its fellow, and the second is small. It has one pair of short chin shields.<ref>[[George Albert Boulenger|Boulenger, GA]]. 1896. pp. 470-471.</ref>
==Geographic range==
These snakes range from northern [[Vietnam]] through southern [[China]] ([[Fujian]], [[Guangxi]], [[Jiangxi]], [[Guizhou]], [[Sichuan]], [[Yunnan]], [[Zhejiang]]), southeast [[Myanmar]] and southeast [[Tibet]]. The [[Type locality (biology)|type locality]] is listed as "Kakhien Hills" (Kachin Hills), [[Myanmar]].<ref name="McD99">[[:fr:Roy Wallace McDiarmid|McDiarmid RW]], [[Jonathan A. Campbell|Campbell JA]], Touré 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).</ref>  The two species are separated by the Red River, with ''A. kharini'' to the east and ''A. feae'' to the west.
==Habitat==
Found in mountainous regions at altitudes up to 1000 m, they prefer cooler climates, with a typical temperature of 20-25&nbsp;°C. Sometimes, they are found on roadsides, in straw and grass, in rice fields, and even in and around homes. In Vietnam, their preferred habitat is described as forests of bamboo and tree ferns, with clearings, where the forest floor is covered with rotting vegetation, with numerous rock outcroppings and many open and subterranean streams. The species is crepuscular, and prefers very moist environments for shelter.<ref name="Mal03"/>
==Behavior==
This snake has a characteristic threat display. When disturbed, it flattens its body to make itself look wider, and its jaws flare outwards posteriorly, giving the normally ovoid head a triangular shape. Sometimes, it  vibrates its tail. Ultimately, it will strike, during which it may or may not use its fangs. As opposed to Orlov (1997), who stated this species is nocturnal, Zhao et al. (1981) reported it to be [[crepuscular]], active from early March into late November.<ref name="Mal03"/>
==Feeding==
They apparently feed on small mammals. A captured, immature specimen was found to have eaten a common gray shrew (''[[Crocidura attenuata]]''). In captivity, these snakes are reported to be reluctant feeders, but when they did feed, they took newborn mice, and then only at night. On several occasions when feeding was observed, the prey was not released after being struck.<ref name="Mal03"/>
==Venom==
The venom profile of Fea's viper is remarkably similar to that of Wagler's viper (''[[Tropidolaemus wagleri]]'').<ref>{{cite web| url= http://www.venomdoc.com/viper.html| title= Dr. Bryan Grieg Fry: Viper Research| access-date= 2006-04-21| archive-url= https://web.archive.org/web/20060511073540/http://www.venomdoc.com/viper.html| archive-date= 2006-05-11| url-status= dead}}</ref>
Another study found the enzyme activities in ''A. feae'' venom-gland extract are similar to those of [[Viperidae|viperine]] venoms, but its venom does not cause blood clotting, [[haemorrhagic]], or [[Myotoxin|myolytic]] activities.
<ref>{{cite journal | title=Studies on venom and venom apparatus of Fea's viper, ''Azemiops feae''. | journal=Toxicon | volume=32 | issue=10 | pages=1275–1278 | date=October 1994 | last1=Mebs | first1=D. | last2=Kuch | first2=U. | last3=Meier | first3=J. |pmid = 8|doi = 10.1016/0006-2952(75)90029-5}}</ref> One toxin found in their venom, [[azemiopsin]], is known to block [[nicotinic acetylcholine receptor]]s in muscles.<ref name="Utkin2012">{{cite journal |last1=Utkin |first1=Yuri N. |date=2012 |title=Azemiopsin from Azemiops feae Viper Venom, a Novel Polypeptide Ligand of Nicotinic Acetylcholine Receptor |url=https://www.researchgate.net/publication/225052935 |journal=Journal of Biological Chemistry |volume=287 |issue=32 |pages=27079–86 |doi=10.1074/jbc.m112.363051 |pmc=3411050 |pmid=22613724 |doi-access=free}}</ref>
==References==
{{Reflist}}
==Further reading==
{{Refbegin}}
*[[species:Bo Beolens|Beolens, Bo]]; [[species:Michael Watkins|Watkins, Michael]]; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. {{ISBN|978-1-4214-0135-5}}. (''Azemiops feae'', p.&nbsp;88).
*[[George Albert Boulenger|Boulenger GA]] (1888). "An Account of the Reptilia obtained in Burma, North of Tenasserim, by M[onsieur]. L. Fea, of the Genoa Civic Museum". ''Annali del Museo Civico di Storia Naturale di Genova, Second Series'' '''6''': 593–604. (''Azemiops'', new genus, p.&nbsp;602; ''A. feae'', new species, p.&nbsp;603).
*Boulenger GA (1896). ''Catalogue of the Snakes in the British Museum (Natural History). Vol. III., Containing the Colubridæ (Opisthoglyphæ and Proteroglyphæ), Amblycephalidæ, and Viperidæ''. London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiv + 727 pp. + Plates I-XXV. (Genus ''Azemiops'', p.&nbsp;470; species ''A. feae'', p.&nbsp;471).
*[[species:Karel Frederik Liem|Liem KF]], [[:fr:Hymen Marx|Marx H]], [[George B. Rabb|Rabb GB]] (1971). "The viperid snake ''Azemiops'': Its comparative cephalic anatomy and phylogenic position in relation to Viperinae and Crotalinae". ''Fieldiana: Zoology, Chicago'' '''59''': 67–126.
*Kardong KV (1986)." Observations on live ''Azemiops feae'', Fea’s viper". ''Herpetological Review'' '''17''' (4): 81–82.
*Mara WP (1993). ''Venomous Snakes of the World''. Hong Kong: TFH Publications. 275 pp. {{ISBN|0-86622-522-6}}.
*Marx H, Olechowski TS (1970). "Fea's viper and the common gray shrew: a distribution note on predator and prey". ''Journal of Mammalogy'' '''51''': 205.
*Mebs D, [[species:Ulrich Kuch|Kuch U]], Meier J (1994). "Studies on venom and venom apparatus of Feae's viper, ''Azemiops feae'' ". ''Toxicon'' '''32''' (10): 1275–1278.
*[[:fr:Nikolaï Orlov|Orlov N]] (1997). "Viperid snakes (Viperidae Bonaparte, 1840) of Tam-Dao mountain range". ''Russian Journal of Herpetology'' '''4''' (1): 67–74.
*[[Zhao Er-mi|Zhao E-m]], Zhao G (1981). "Notes on Fea's viper from China". ''Acta Herpetologica Sinica'' '''5''' (11): 66–71.
{{Refend}}
==External links==
{{Commons|Azemiopinae}}
* {{NRDB species|genus=Azemiops|species=feae|date=2 August|year=2007}}
* [http://snakesarelong.blogspot.com/2013/04/feas-viper.html Fea's Viper at Life is Short but Snakes are Long]
* {{YouTube|uXnoqLJyi2w|Video of ''Azemiops feae''}}. Accessed 25 May 2007.
{{Taxonbar|from=Q13416836|from2=Q13416835}}
{{Authority control}}
[[Category:Azemiopinae| ]]
[[Category:Reptiles of Myanmar]]
[[Category:Reptiles of China]]
[[Category:Reptiles of Vietnam]]
[[Category:Snakes of Vietnam]]
[[Category:Snakes of Asia]]
[[Category:Venomous snakes]]
[[Category:Snake genera]]