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K Reverting possible vandalism by 72.20.156.243 to version by 149.169.132.238. Report False Positive? Thanks, ClueBot NG. (2531979) (Bot)
Edited previous wording and rearranged some sections for better flow. Also updated Habitat, Distribution, Evolution and Taxonomy to better reflect recent scientific literature, added appropriate references.
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[[File:Pelamis platura yellow form Costa Rica.jpg|thumbnail|Yellow form from the Pacific coast of Costa Rica]]
[[File:Pelamis platura yellow form Costa Rica.jpg|thumbnail|Yellow form from the Golfo Dulce on the Pacific coast of Costa Rica]]
'''''Pelamis platura''''', commonly known as the '''yellow-bellied sea snake''', '''yellowbelly sea snake''', or '''pelagic sea snake''', is a [[species]] of [[Hydrophiidae|sea snake]] found in [[tropical]] oceanic waters around the world, excluding the Atlantic Ocean.
'''''Pelamis platura''''', commonly known as the '''yellow-bellied sea snake''', '''yellowbelly sea snake''', or '''pelagic sea snake''', is a [[species]] of [[Hydrophiidae|sea snake]] found in [[tropical]] oceanic waters around the world, excluding the Atlantic Ocean.
It is the [[monotypic taxon|only member]] of the [[genus]] ''Pelamis''.
It is the [[monotypic taxon|only member]] of the [[genus]] ''Pelamis''.


==Description==
==Description==
[[Image:pelamis platuras.jpg|thumb|left|200px|''Pelamis platurus'', related to the cobra family ([[Elapidae]])]]
[[Image:pelamis platuras.jpg|thumb|left|200px|''Pelamis platurus'', a front-fanged venomous snake, related to the brown snakes, cobras and taipans ([[Elapidae]])]]


:''See [[snake scales]] for terminology used here''
:''See [[snake scales]] for terminology used here''
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==Habitats==
==Habitats==
The yellow-bellied sea snake, like many other species of sea snake, are fully adapted to living their whole lives at sea: mating, eating and giving birth to live young. They breed in warm waters; they are [[ovoviviparous]] with a gestation period around 6 months. According to [[Raymond Ditmars|Ditmars]], females bear live young in tidal pools.<ref>[[Karl Patterson Schmidt|Schmidt, K.P.]] & D.D. Davis. 1941. ''Field Book of Snakes of the United States and Canada''. G.P. Putnam's Sons. New York. p. 280.</ref> They move poorly on land due to their smaller belly scales that form a [[Anatomical terms of location|ventral]] [[keel]]<ref name=":0">{{Cite journal|last = Brischoux|first = François|last2 = Shine|first2 = Richard|date = 2011-05-01|title = Morphological adaptations to marine life in snakes|url = http://www.ncbi.nlm.nih.gov/pubmed/21337377|journal = Journal of Morphology|volume = 272|issue = 5|pages = 566–572|doi = 10.1002/jmor.10933|issn = 1097-4687|pmid = 21337377}}</ref>. They are sometimes observed in large aggregations of thousands on the surface of the water in oceanic [[Natural lines of drift|drift lines]], which has been proposed as a strategy to catch prey<ref>{{Cite journal|last = Brischoux|first = François|last2 = Lillywhite|first2 = Harvey B.|date = 2011-06-14|title = Light- and flotsam-dependent ‘float-and-wait’ foraging by pelagic sea snakes (Pelamis platurus)|url = http://link.springer.com/article/10.1007/s00227-011-1738-z|journal = Marine Biology|language = en|volume = 158|issue = 10|pages = 2343–2347|doi = 10.1007/s00227-011-1738-z|issn = 0025-3162}}</ref>. They hunt by floating on the surface of the water to attract [[Pelagic fish|pelagic]] fish that are seeking shelter, prey are captured via a backwards swimming motion and rapid lunge of the jaws<ref name=":1">{{Cite book|title = Fauna of Australia: Family Hydrophiinae|last = Heatwole|first = Harold|publisher = AGPS|year = 1993|isbn =|location = Canberra|pages = 15}}</ref>. Heatwole proposed that these snakes find their prey by sensing the vibration generated by fish movement<ref>{{Cite book|url = https://books.google.com/books?id=80ERtB6qgGgC|title = Sea Snakes|last = Heatwole|first = Harold|date = 1999-01-01|publisher = UNSW Press|isbn = 9780868407760|language = en}}</ref>. Fish are subdued by [[neurotoxic]] venom and swallowed whole.
These snakes breed in warm waters; they are [[ovoviviparous]] with a gestation period around 6 months. According to [[Raymond Ditmars|Ditmars]], females bear live young in tidal pools.<ref>[[Karl Patterson Schmidt|Schmidt, K.P.]] & D.D. Davis. 1941. ''Field Book of Snakes of the United States and Canada''. G.P. Putnam's Sons. New York. p. 280.</ref> They are helpless on land,{{citation_needed|date=October 2015}} and they sometimes form large aggregations of thousands in surface waters. These snakes use their [[neurotoxic]] venom against their fish prey. No human fatalities from envenomation are known.


They have a special salt gland located in the lower jaw that is used to filter out salt from the surrounding sea water<ref>{{Cite journal|last = Dunson|first = William A.|last2 = Packer|first2 = Randall K.|last3 = Dunson|first3 = Margaret K.|date = 1971-01-01|title = Sea Snakes: An Unusual Salt Gland under the Tongue|url = http://www.jstor.org/stable/1732639|journal = Science|volume = 173|issue = 3995|pages = 437–441}}</ref>. Contrary to past beliefs, sea snakes require fresh water to survive and the yellow-bellied sea snake drinks precipitation that forms on the surface of sea water<ref>{{Cite journal|last = Lillywhite|first = Harvey B.|last2 = Brischoux|first2 = François|last3 = Sheehy|first3 = Coleman M.|last4 = Pfaller|first4 = Joseph B.|date = 2012-08-01|title = Dehydration and drinking responses in a pelagic sea snake|url = http://www.ncbi.nlm.nih.gov/pubmed/22510231|journal = Integrative and Comparative Biology|volume = 52|issue = 2|pages = 227–234|doi = 10.1093/icb/ics039|issn = 1557-7023|pmid = 22510231}}</ref>. This species has been reported to survive severe dehydration of up to 7 months during seasonal drought<ref>{{Cite journal|last = Lillywhite|first = Harvey B.|last2 = Sheehy|first2 = Coleman M.|last3 = Brischoux|first3 = François|last4 = Grech|first4 = Alana|date = 2014-05-07|title = Pelagic sea snakes dehydrate at sea|url = http://rspb.royalsocietypublishing.org/content/281/1782/20140119|journal = Proceedings of the Royal Society of London B: Biological Sciences|language = en|volume = 281|issue = 1782|pages = 20140119|doi = 10.1098/rspb.2014.0119|issn = 0962-8452|pmc = 3973276|pmid = 24648228}}</ref>.
As they live only in the ocean, they must get all of their food and water there. However, they do not have the ability to filter all the salt from seawater, although they can do it for food. To survive severe dehydration, they wait for months until the rainy season, when rainwater sits on top of the heavier saltwater below, then drink the surface water with lower salt concentration.<ref>http://rspb.royalsocietypublishing.org/content/281/1782/20140119</ref>


==Distribution==
==Distribution==
The yellow-bellied sea snake is one of the most widely distributed snakes in the world<ref name=":2">{{Cite journal|last = Rasmussen|first = Arne Redsted|last2 = Murphy|first2 = John C.|last3 = Ompi|first3 = Medy|last4 = Gibbons|first4 = J. Whitfield|last5 = Uetz|first5 = Peter|title = Marine Reptiles|url = http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0027373|journal = PLoS ONE|volume = 6|issue = 11|doi = 10.1371/journal.pone.0027373|pmc = 3210815|pmid = 22087300}}</ref> and has an extensive distribution covering the entire tropical [[Indo-Pacific]]. It is completely [[pelagic]] and is often observed on oceanic [[Natural lines of drift|drift lines]], using surface currents and storms to move around the ocean<ref name=":1" />. Their distribution appears to be largely determined by favourable water temperatures, [[Ocean current|oceanic currents]] and recent formation of [[Land bridge|land bridges]] that have blocked farther dispersal.
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The yellowbelly is the most widely distributed sea snake and is capable of living and giving birth entirely in the open sea (it is completely [[pelagic]]), being found in all coastal waters around the rim of the [[Pacific Ocean]] except [[Alaska]] south to southern [[California]], and in the coastal waters of the [[Indian Ocean]] from the [[Persian Gulf]] eastwards. It is the only sea snake to have reached the [[Hawaiian Islands]].<ref>Liptow, J. 1999. "''Pelamis platurus''" (On-line), Animal Diversity Web. Accessed June 23, 2007 at [http://animaldiversity.ummz.umich.edu/site/accounts/information/Pelamis_platurus.html]</ref> The sea snake has also been reported around the shores of [[New Zealand]],<ref name="WaikatoTimes2012">{{cite news |title=Swimmers told not to be surprised of poisonous sea snake |url=http://www.stuff.co.nz/waikato-times/news/6213293/Swimmers-told-not-to-be-surprised-of-poisonous-sea-snake |newspaper=Waikato Times |publisher=[[Fairfax New Zealand]] |location=[[Hamilton, New Zealand]] |date=4 January 2012 |accessdate=26 April 2012}}</ref> a country that would otherwise be free of snakes were it not for the infrequent visits of yellowbellies and [[Laticauda colubrina|banded sea kraits]].<ref name="AucklandMuseum">{{cite web |url=http://www.aucklandmuseum.com/349/natural-history-questions##2 |title=Natural History Questions |author=Natural History Information Centre, Auckland War Memorial Museum |work=Auckland War Memorial Museum {{pipe}} Tamaki Paenga Hira |publisher=[[Auckland War Memorial Museum]] |location=[[Auckland]], New Zealand |at=Q. Are there any snakes in New Zealand? |accessdate=26 April 2012}}</ref>


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They hare found in all coastal waters around the rim of the [[Pacific Ocean]] except [[Alaska]] south to southern [[California]], and in the coastal waters of the [[Indian Ocean]] from the [[Persian Gulf]] eastwards. It is the only sea snake to have reached the [[Hawaiian Islands]].<ref>Liptow, J. 1999. "''Pelamis platurus''" (On-line), Animal Diversity Web. Accessed June 23, 2007 at [http://animaldiversity.ummz.umich.edu/site/accounts/information/Pelamis_platurus.html]</ref> The sea snake has also been reported around the shores of [[New Zealand]],<ref name="WaikatoTimes2012">{{cite news |title=Swimmers told not to be surprised of poisonous sea snake |url=http://www.stuff.co.nz/waikato-times/news/6213293/Swimmers-told-not-to-be-surprised-of-poisonous-sea-snake |newspaper=Waikato Times |publisher=[[Fairfax New Zealand]] |location=[[Hamilton, New Zealand]] |date=4 January 2012 |accessdate=26 April 2012}}</ref> a country that would otherwise be free of snakes were it not for the infrequent visits of yellow-bellied sea snake and [[Laticauda colubrina|banded sea kraits]].<ref name="AucklandMuseum">{{cite web |url=http://www.aucklandmuseum.com/349/natural-history-questions##2 |title=Natural History Questions |author=Natural History Information Centre, Auckland War Memorial Museum |work=Auckland War Memorial Museum {{pipe}} Tamaki Paenga Hira |publisher=[[Auckland War Memorial Museum]] |location=[[Auckland]], New Zealand |at=Q. Are there any snakes in New Zealand? |accessdate=26 April 2012}}</ref>
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The yellowbellied sea snake (''Pelamis platura'', previously known as ''Pelamis platurus'') has also been reported to occur in the Agulhas Current along the east coast of Southern Africa. A specimen was found washed ashore (01-09-2014) after a storm and deposited on the sandy beach at Boesmansrivermouth, (near Port Alfred), Easter Cape Province, South Africa.<ref>Also see references in ''The Living Shores of Southern Africa'', Margo and George Branch, Page 130 - 131, Macmillan South Africa (Publishers), Johannesburg and "Snake versus Man" [[Johan Marais]], page 50 - 51, C. Struik Publishers, Cape Town.</ref>
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Yellowbellies (and all other sea snakes) are not found in the [[Atlantic]] or [[Mediterranean]], though the water there is warm enough. Yellowbellies require a minimum of 16–18°C (60.8 to 64.4°F) to survive long term.<ref>(Dunson and Ehlert 1971).</ref> Yellowbellies have not migrated around the southern tips of [[South America]] or [[South Africa]] because water temperatures are too cool. In October 2015, yellowbellies were reported and photographed on beaches in [[Ventura County, California]], well outside their normal range, for the first time in 30 years.<ref>{{Cite web|title = Blame El Niño for poisonous sea snake found on Ventura County beach|url = http://www.latimes.com/local/lanow/la-me-ln-venomous-sea-snake-found-20151016-story.html|website = latimes.com|accessdate = 2015-10-25}}</ref> This change is believed to be associated with higher than usual coastal water temperatures associated with [[el Niño]].<ref>{{Cite web|title = El Nino brings sea snake to California's coast - CNN.com|url = http://www.cnn.com/2015/10/17/us/sea-snake-california-el-nino/index.html|website = CNN|accessdate = 2015-10-25}}</ref>


⚫
The yellow-bellied sea snake has also been reported to occur in the [[Agulhas Current]] along the east coast of Southern Africa. A specimen was found washed ashore (01-09-2014) after a storm and deposited on the sandy beach at Boesmansrivermouth, (near Port Alfred), Easter Cape Province, South Africa.<ref>Also see references in ''The Living Shores of Southern Africa'', Margo and George Branch, Page 130 - 131, Macmillan South Africa (Publishers), Johannesburg and "Snake versus Man" [[Johan Marais]], page 50 - 51, C. Struik Publishers, Cape Town.</ref>
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A land bridge formed (at [[Panama]]) between North and South America about 3 million years ago, making it impossible for them to enter the [[Caribbean Sea]] from the Pacific. If they had reached the eastern [[Pacific Ocean]] before the land bridge formed, they would almost certainly be found now in the Atlantic. The [[Panama Canal]] has not made a crossing of the isthmus possible because it is [[fresh water]].
⚫
Yellow-bellied sea snakes (and all other sea snakes) are not found in the [[Atlantic]] or [[Mediterranean]], though the water there is warm enough. They require a minimum of 16–18°C (60.8 to 64.4°F) to survive long term.<ref>(Dunson and Ehlert 1971).</ref> Yellowbellies have not migrated around the southern tips of [[South America]] or [[South Africa]] because water temperatures are too cool. In October 2015, they were reported and photographed on beaches in [[Ventura County, California]], well outside their normal range, for the first time in 30 years.<ref>{{Cite web|title = Blame El Niño for poisonous sea snake found on Ventura County beach|url = http://www.latimes.com/local/lanow/la-me-ln-venomous-sea-snake-found-20151016-story.html|website = latimes.com|accessdate = 2015-10-25}}</ref> This change is believed to be associated with higher than usual coastal water temperatures associated with [[el Niño]].<ref>{{Cite web|title = El Nino brings sea snake to California's coast - CNN.com|url = http://www.cnn.com/2015/10/17/us/sea-snake-california-el-nino/index.html|website = CNN|accessdate = 2015-10-25}}</ref>


⚫
A [[land bridge]] formed (at [[Panama]]) between North and South America about 3 million years ago, making it impossible for them to enter the [[Caribbean Sea]] from the Pacific. If they had reached the eastern [[Pacific Ocean]] before the land bridge formed, they would almost certainly be found now in the Atlantic. The [[Panama Canal]] has not made a crossing of the isthmus possible because it is [[fresh water]].
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They do not live in the [[Red Sea]] because of its excessive [[salinity]].

⚫
They do not live in the [[Red Sea]] because of its excessive [[salinity]] <!-- citation needed -->.

Due to the wide distribution of the species and relative lack of [[Biological dispersal|dispersal barriers]], it has been assumed that individuals from different localities represent a single breeding [[Population genetics|population]] (i.e. high [[gene flow]]). However, a study that used [[haplotype]] networks in two populations from [[Costa Rica]] suggests that shallow genetic population structure exists which reflects variation in colour patterns (brown and yellow in [[Gulf of Papagayo|Golfo de Papagayo]] and completely yellow in [[Golfo Dulce, Costa Rica|Golfo Dulce]])<ref>{{Cite journal|last = Sheehy|first = Coleman M.|last2 = Solórzano|first2 = Alejandro|last3 = Pfaller|first3 = Joseph B.|last4 = Lillywhite|first4 = Harvey B.|date = 2012-08-01|title = Preliminary insights into the phylogeography of the yellow-bellied sea snake, Pelamis platurus|url = http://www.ncbi.nlm.nih.gov/pubmed/22659201|journal = Integrative and Comparative Biology|volume = 52|issue = 2|pages = 321–330|doi = 10.1093/icb/ics088|issn = 1557-7023|pmid = 22659201}}</ref>.


==Evolution==
==Evolution==
Sea snakes are a [[Monophyly|monophyletic]] group ([[Hydrophiinae]]) that diverged from the front-fanged [[Australasia|Austlalasian]] [[Venomous snake|venomous]] snakes ([[Elapidae]]) about 10 million years ago<ref>{{Cite journal|last = Lukoschek|first = Vimoksalehi|last2 = Keogh|first2 = J. Scott|date = 2006-11-01|title = Molecular phylogeny of sea snakes reveals a rapidly diverged adaptive radiation|url = http://onlinelibrary.wiley.com/doi/10.1111/j.1095-8312.2006.00691.x/abstract|journal = Biological Journal of the Linnean Society|language = en|volume = 89|issue = 3|pages = 523–539|doi = 10.1111/j.1095-8312.2006.00691.x|issn = 1095-8312}}</ref><ref>{{Cite journal|last = Pyron|first = R. Alexander|last2 = Burbrink|first2 = Frank T.|last3 = Colli|first3 = Guarino R.|last4 = de Oca|first4 = Adrian Nieto Montes|last5 = Vitt|first5 = Laurie J.|last6 = Kuczynski|first6 = Caitlin A.|last7 = Wiens|first7 = John J.|date = 2011-02-01|title = The phylogeny of advanced snakes (Colubroidea), with discovery of a new subfamily and comparison of support methods for likelihood trees|url = http://www.ncbi.nlm.nih.gov/pubmed/21074626|journal = Molecular Phylogenetics and Evolution|volume = 58|issue = 2|pages = 329–342|doi = 10.1016/j.ympev.2010.11.006|issn = 1095-9513|pmid = 21074626}}</ref>. The yellow-bellied sea snake is a part of the rapidly radiating [[Hydrophis]] group<ref>{{Cite journal|last = Sanders|first = Kate L.|last2 = Lee|first2 = Michael S. Y.|last3 = Mumpuni|last4 = Bertozzi|first4 = Terry|last5 = Rasmussen|first5 = Arne R.|date = 2013-03-01|title = Multilocus phylogeny and recent rapid radiation of the viviparous sea snakes (Elapidae: Hydrophiinae)|url = http://www.sciencedirect.com/science/article/pii/S1055790312003788|journal = Molecular Phylogenetics and Evolution|volume = 66|issue = 3|pages = 575–591|doi = 10.1016/j.ympev.2012.09.021}}</ref>.
The yellowbelly seems to have evolved from the terrestrial [[Elapidae|elapid]]s of Asia and Australia about 10 million years ago. This air-breathing sea snake has developed a flat, oar-like tail and valved nostrils since leaving the land millions of years ago.<ref>The New York Times, published 24 April 1984, article by Sandra Blakeslea http://query.nytimes.com/gst/fullpage.html?res=9903E2DD1238F937A15757C0A962948260&sec=health&spon= Accessed May 2008</ref><ref>Linnaeus 12th edition.</ref>

Adaptations to aquatic life include the laterally compressed body and oar-like tail for swimming<ref>{{Cite journal|last = Sanders|first = Kate L.|last2 = Rasmussen|first2 = Arne R.|last3 = Elmberg|first3 = Johan|date = 2012-08-01|title = Independent Innovation in the Evolution of Paddle-Shaped Tails in Viviparous Sea Snakes (Elapidae: Hydrophiinae)|url = http://icb.oxfordjournals.org/content/52/2/311|journal = Integrative and Comparative Biology|language = en|volume = 52|issue = 2|pages = 311–320|doi = 10.1093/icb/ics066|issn = 1540-7063|pmid = 22634358}}</ref><ref name=":3">{{Cite journal|first = F.|last2 = Shine|first2 = R.|date = 2008-04-01|title = The origin of evolutionary innovations: locomotor consequences of tail shape in aquatic snakes|url = http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2435.2007.01359.x/abstract|journal = Functional Ecology|language = en|volume = 22|issue = 2|pages = 317–322|doi = 10.1111/j.1365-2435.2007.01359.x|issn = 1365-2435}}</ref>, valved nostrils and [[Palatine uvula|palatine]] seal for excluding sea water, and [[Skin|cutaneous]] [[gas exchange]] for prolonging dive times<ref>{{Cite journal|last = Seymour|first = Roger S.|date = 1974-08-09|title = How sea snakes may avoid the bends|url = http://www.nature.com/nature/journal/v250/n5466/abs/250489a0.html|journal = Nature|language = en|volume = 250|issue = 5466|pages = 489–490|doi = 10.1038/250489a0}}</ref><ref name=":3" /><ref name=":0" />.


==Taxonomy==
==Taxonomy==
Sea snakes are closely related to the venomous Australian snakes of the family [[Elapidae]], but are sometimes classified in a separate family, the [[Hydrophiidae]]. Two subfamilies have been listed in the past, the sea kraits ([[Laticaudinae]]), and the true sea snakes ([[Hydrophiinae]]), though recent work suggests this subfamilial division may be inappropriate.<ref>[http://www.toxinology.com/generic_static_files/cslavh_antivenom_seasnake.html CSL Antivenom Handbook – Sea Snake Antivenom<!-- Bot generated title -->]</ref>
Sea snakes are a subfamily [[Hydrophiidae|(Hydrophiinae]]) of the venomous [[Australasia|Australasian]] snakes of the family [[Elapidae]]. Traditionally, sea snakes and [[Laticauda|sea kraits]] were considered to be a part of a single family ([[Hydrophiinae|Hydrophiidae]]), but sea kraits have since been placed into a separate subfamily ([[Laticaudinae]]) due to their independent evolution into aquatic habitats (i.e. [[convergent evolution]])<ref name=":2" /><ref>[http://www.toxinology.com/generic_static_files/cslavh_antivenom_seasnake.html CSL Antivenom Handbook – Sea Snake Antivenom<!-- Bot generated title -->]</ref> .


In 1766, [[Linnaeus]] published the original description of the yellow-bellied sea snake, naming it ''Anguis platura'' (''Anguis'' meaning snake). In 1803, Daudin created the new [[genus]] ''Pelamis'' and assigned this [[species]] to it, referring to it as ''Pelamis platuros''. In 1842, Gray described what he thought was a new species and called it ''Pelamis ornata'' (subsequently ''P. ornata'' became a synonym of ''P. platura''). The word ''Pelamis'' is a feminine noun and means young or small tunny fish. In 1872, [[Stoliczka]] introduced the name ''Pelamis platurus'' (still the most used scientific name by scientists today), but used the incorrect ending ''-us'' instead of ''-a'' which a feminine noun requires.<ref>Tropical zoology 13:327–329, 2000, The gender of the genera ... ''Pelamis'' Daudin 1803 (hydrophiidae) B Lanza and S, Boscherini – Accessed online May, 2008</ref> A few recent examples exist of scientists' beginning to use the grammatically correct name ''Pelamis platura'', e.g., Bohme 2003 and the Reptile Database with its page headed ''Pelamis platura'' (Linnaeus, 1766), which includes an extensive synonymy of the different scientific names which have been used for the yellowbelly sea snake.<ref>{{NRDB species|genus=Pelamis|species=platura}}. Accessed May 2008</ref>
In 1766, [[Linnaeus]] published the original description of the yellow-bellied sea snake, naming it ''Anguis platura'' (''Anguis'' meaning snake). In 1803, Daudin created the new [[genus]] ''Pelamis'' and assigned this [[species]] to it, referring to it as ''Pelamis platuros''. In 1842, Gray described what he thought was a new species and called it ''Pelamis ornata'' (subsequently ''P. ornata'' became a synonym of ''P. platura'').

To further complicate the [[nomenclature]], the taxonomic status of sea snakes is still under review, with recent authors suggesting a dismantling of [[Monotypic taxon|monotypic]] genera, such as ''Pelamis'', in favour of a single genus, [[Hydrophis|''Hydrophis'']], in order to reduce [[paraphyly]] and better reflect [[Phylogenetic relationship|phylogenetic relationships]]<ref>{{Cite journal|last = Rasmussen|first = Arne Redsted|last2 = Sanders|first2 = Kate Laura|last3 = Guinea|first3 = Michael L.|last4 = Amey|first4 = Andrew P.|date = 2014-01-01|title = Sea snakes in Australian waters (Serpentes: subfamilies Hydrophiinae and Laticaudinae)-a review with an updated identification key|url = http://www.ncbi.nlm.nih.gov/pubmed/25283923|journal = Zootaxa|volume = 3869|pages = 351–371|issn = 1175-5334|pmid = 25283923}}</ref>.


==Name==
==Name==
The genus name ''Pelamis'' is derived from the [[Ancient Greek]] word for "tunny fish", which presumably refers to the habitat or what [[Daudin]] thought they ate. The specific name ''platurus'' is a combination of the Ancient Greek words ''platys'' "flat" and ''oura'' "tail", referring to the flattened tail.
The genus name ''Pelamis'' is derived from the [[Ancient Greek]] word for "tunny fish", which presumably refers to the habitat or what [[Daudin]] thought they ate. The specific name ''platurus'' is a combination of the Ancient Greek words ''platys'' "flat" and ''oura'' "tail", referring to the flattened tail.

The word ''Pelamis'' is a feminine noun and means young or small tunny fish. In 1872, [[Stoliczka]] introduced the name ''Pelamis platurus'' (still the most used scientific name by scientists today), but used the incorrect ending ''-us'' instead of ''-a'' which a feminine noun requires.<ref>Tropical zoology 13:327–329, 2000, The gender of the genera ... ''Pelamis'' Daudin 1803 (hydrophiidae) B Lanza and S, Boscherini – Accessed online May, 2008</ref> A few recent examples exist of scientists' beginning to use the grammatically correct name ''Pelamis platura'', e.g., Bohme 2003 and the Reptile Database with its page headed ''Pelamis platura'' (Linnaeus, 1766), which includes an extensive synonymy of the different scientific names which have been used for the yellow-bellied sea snake.<ref>{{NRDB species|genus=Pelamis|species=platura}}. Accessed May 2008</ref>


==Venom==
==Venom==

Version vom 29. März 2016, 14:58 Uhr

Vorlage:Italic title

Systematik
Yellow form from the Golfo Dulce on the Pacific coast of Costa Rica

Pelamis platura, commonly known as the yellow-bellied sea snake, yellowbelly sea snake, or pelagic sea snake, is a species of sea snake found in tropical oceanic waters around the world, excluding the Atlantic Ocean. It is the only member of the genus Pelamis.

Description

Pelamis platurus, a front-fanged venomous snake, related to the brown snakes, cobras and taipans (Elapidae)
See snake scales for terminology used here

The body of this snake is compressed, with the posterior less than half the diameter of the neck; the body scales are juxtaposed, subquadrangular in shape, and in 23–47 rows around the thickest part of the body; ventral scales, 264–406 in number, are very small and, if distinct, divided by a longitudinal groove, but usually are indistinguishable from adjacent body scales. The head is narrow, with an elongated snout; head shields are entire, nostrils are superior, and nasal shields are in contact with one another; the prefrontal scale is in contact with second upper labial; one or two preoculars, two or three postoculars, and two or three small anterior temporals are present; seven or eight upper labials are found, with four or five below the eye, but separated from the border by a subocular. Colors of the snake are variable, but most often distinctly bicolored, black above, yellow or brown below, with the dorsal and ventral colors sharply demarcated from one another; ventrally, there may be a series of black spots or bars on the yellow or brown background, or the yellow may extend dorsally so there is only a narrow middorsal black stripe, or a series of black crossbars.[1] Total length for males is up to Vorlage:Convert, for females up to Vorlage:Convert; tail length for males is up to Vorlage:Convert, females up to Vorlage:Convert.

Habitats

The yellow-bellied sea snake, like many other species of sea snake, are fully adapted to living their whole lives at sea: mating, eating and giving birth to live young. They breed in warm waters; they are ovoviviparous with a gestation period around 6 months. According to Ditmars, females bear live young in tidal pools.[2] They move poorly on land due to their smaller belly scales that form a ventral keel[3]. They are sometimes observed in large aggregations of thousands on the surface of the water in oceanic drift lines, which has been proposed as a strategy to catch prey[4]. They hunt by floating on the surface of the water to attract pelagic fish that are seeking shelter, prey are captured via a backwards swimming motion and rapid lunge of the jaws[5]. Heatwole proposed that these snakes find their prey by sensing the vibration generated by fish movement[6]. Fish are subdued by neurotoxic venom and swallowed whole.

They have a special salt gland located in the lower jaw that is used to filter out salt from the surrounding sea water[7]. Contrary to past beliefs, sea snakes require fresh water to survive and the yellow-bellied sea snake drinks precipitation that forms on the surface of sea water[8]. This species has been reported to survive severe dehydration of up to 7 months during seasonal drought[9].

Distribution

The yellow-bellied sea snake is one of the most widely distributed snakes in the world[10] and has an extensive distribution covering the entire tropical Indo-Pacific. It is completely pelagic and is often observed on oceanic drift lines, using surface currents and storms to move around the ocean[5]. Their distribution appears to be largely determined by favourable water temperatures, oceanic currents and recent formation of land bridges that have blocked farther dispersal.

They hare found in all coastal waters around the rim of the Pacific Ocean except Alaska south to southern California, and in the coastal waters of the Indian Ocean from the Persian Gulf eastwards. It is the only sea snake to have reached the Hawaiian Islands.[11] The sea snake has also been reported around the shores of New Zealand,[12] a country that would otherwise be free of snakes were it not for the infrequent visits of yellow-bellied sea snake and banded sea kraits.[13]

The yellow-bellied sea snake has also been reported to occur in the Agulhas Current along the east coast of Southern Africa. A specimen was found washed ashore (01-09-2014) after a storm and deposited on the sandy beach at Boesmansrivermouth, (near Port Alfred), Easter Cape Province, South Africa.[14] Yellow-bellied sea snakes (and all other sea snakes) are not found in the Atlantic or Mediterranean, though the water there is warm enough. They require a minimum of 16–18°C (60.8 to 64.4°F) to survive long term.[15] Yellowbellies have not migrated around the southern tips of South America or South Africa because water temperatures are too cool. In October 2015, they were reported and photographed on beaches in Ventura County, California, well outside their normal range, for the first time in 30 years.[16] This change is believed to be associated with higher than usual coastal water temperatures associated with el Niño.[17]

A land bridge formed (at Panama) between North and South America about 3 million years ago, making it impossible for them to enter the Caribbean Sea from the Pacific. If they had reached the eastern Pacific Ocean before the land bridge formed, they would almost certainly be found now in the Atlantic. The Panama Canal has not made a crossing of the isthmus possible because it is fresh water.

They do not live in the Red Sea because of its excessive salinity .

Due to the wide distribution of the species and relative lack of dispersal barriers, it has been assumed that individuals from different localities represent a single breeding population (i.e. high gene flow). However, a study that used haplotype networks in two populations from Costa Rica suggests that shallow genetic population structure exists which reflects variation in colour patterns (brown and yellow in Golfo de Papagayo and completely yellow in Golfo Dulce)[18].

Evolution

Sea snakes are a monophyletic group (Hydrophiinae) that diverged from the front-fanged Austlalasian venomous snakes (Elapidae) about 10 million years ago[19][20]. The yellow-bellied sea snake is a part of the rapidly radiating Hydrophis group[21].

Adaptations to aquatic life include the laterally compressed body and oar-like tail for swimming[22][23], valved nostrils and palatine seal for excluding sea water, and cutaneous gas exchange for prolonging dive times[24][23][3].

Taxonomy

Sea snakes are a subfamily (Hydrophiinae) of the venomous Australasian snakes of the family Elapidae. Traditionally, sea snakes and sea kraits were considered to be a part of a single family (Hydrophiidae), but sea kraits have since been placed into a separate subfamily (Laticaudinae) due to their independent evolution into aquatic habitats (i.e. convergent evolution)[10][25] .

In 1766, Linnaeus published the original description of the yellow-bellied sea snake, naming it Anguis platura (Anguis meaning snake). In 1803, Daudin created the new genus Pelamis and assigned this species to it, referring to it as Pelamis platuros. In 1842, Gray described what he thought was a new species and called it Pelamis ornata (subsequently P. ornata became a synonym of P. platura).

To further complicate the nomenclature, the taxonomic status of sea snakes is still under review, with recent authors suggesting a dismantling of monotypic genera, such as Pelamis, in favour of a single genus, Hydrophis, in order to reduce paraphyly and better reflect phylogenetic relationships[26].

Name

The genus name Pelamis is derived from the Ancient Greek word for "tunny fish", which presumably refers to the habitat or what Daudin thought they ate. The specific name platurus is a combination of the Ancient Greek words platys "flat" and oura "tail", referring to the flattened tail.

The word Pelamis is a feminine noun and means young or small tunny fish. In 1872, Stoliczka introduced the name Pelamis platurus (still the most used scientific name by scientists today), but used the incorrect ending -us instead of -a which a feminine noun requires.[27] A few recent examples exist of scientists' beginning to use the grammatically correct name Pelamis platura, e.g., Bohme 2003 and the Reptile Database with its page headed Pelamis platura (Linnaeus, 1766), which includes an extensive synonymy of the different scientific names which have been used for the yellow-bellied sea snake.[28]

Venom

The venom of this species is highly potent, like other sea snakes.[29] The subcutaneous Vorlage:LD50 of the venom is 0.067 mg/kg and the venom yield per bite is 1.0–4.0 mg.[30][31]

Antivenom

Sea snake venom can cause damage to skeletal muscle with consequent myoglobinuria, neuromuscular paralysis or direct renal damage. The venoms of significant species of sea snake are neutralised with Commonwealth Serum Laboratories Ltd (of Melbourne, Australia) sea snake (Enhydrina schistosa) antivenom. If that preparation is not available, tiger snake or polyvalent antivenom should be used. No deaths have been recorded from bites in Australian waters.[32][33] The E. schistosa antivenom was tested specifically on Pelamus platurus, and it effectively neutralised the venom.[34]

See also

Cited references

Vorlage:Reflist

Other sources

  • Ditmars, R.L. 1936. The Reptiles of North America. Doubleday, Doran & Co. New York. 476 pp.
  • Hecht, M. K., Kropach, C. and Hecht, B. M. 1974 Distribution of the yellow-bellied sea snake Pelamis platurus, and its significance in relation to the fossil record. Herpetologica 30: 387–395.
  • Kropach, C. 1975 The yellow-bellied sea snake, Pelamis, in the eastern Pacific. Pp. 185–213 in: Dunson, W., ed., The Biology of Sea Snakes. Univ. Park Press, Baltimore, xi + 530 pp.
  • Smith, M.A. 1943. The Fauna of British India, Ceylon and Burma, including the Whole of the Indo-Chinese Sub-region. Reptiles and Amphibians. Vol. III. – Serpentes. Taylor & Francis. London. 583 pp.
  1. ↑ (M.A. Smith, 1943: 476–477, gives more complete descriptions of the color pattern variants).
  2. ↑ Schmidt, K.P. & D.D. Davis. 1941. Field Book of Snakes of the United States and Canada. G.P. Putnam's Sons. New York. p. 280.
  3. ↑ a b François Brischoux, Richard Shine: Morphological adaptations to marine life in snakes. In: Journal of Morphology. 272. Jahrgang, Nr. 5, 1. Mai 2011, ISSN 1097-4687, S. 566–572, doi:10.1002/jmor.10933, PMID 21337377 (nih.gov).
  4. ↑ François Brischoux, Harvey B. Lillywhite: Light- and flotsam-dependent ‘float-and-wait’ foraging by pelagic sea snakes (Pelamis platurus). In: Marine Biology. 158. Jahrgang, Nr. 10, 14. Juni 2011, ISSN 0025-3162, S. 2343–2347, doi:10.1007/s00227-011-1738-z (englisch, springer.com).
  5. ↑ a b Harold Heatwole: Fauna of Australia: Family Hydrophiinae. AGPS, Canberra 1993, S. 15.
  6. ↑ Harold Heatwole: Sea Snakes. UNSW Press, 1999, ISBN 978-0-86840-776-0 (englisch, google.com).
  7. ↑ William A. Dunson, Randall K. Packer, Margaret K. Dunson: Sea Snakes: An Unusual Salt Gland under the Tongue. In: Science. 173. Jahrgang, Nr. 3995, 1. Januar 1971, S. 437–441 (jstor.org).
  8. ↑ Harvey B. Lillywhite, François Brischoux, Coleman M. Sheehy, Joseph B. Pfaller: Dehydration and drinking responses in a pelagic sea snake. In: Integrative and Comparative Biology. 52. Jahrgang, Nr. 2, 1. August 2012, ISSN 1557-7023, S. 227–234, doi:10.1093/icb/ics039, PMID 22510231 (nih.gov).
  9. ↑ Harvey B. Lillywhite, Coleman M. Sheehy, François Brischoux, Alana Grech: Pelagic sea snakes dehydrate at sea. In: Proceedings of the Royal Society of London B: Biological Sciences. 281. Jahrgang, Nr. 1782, 7. Mai 2014, ISSN 0962-8452, S. 20140119, doi:10.1098/rspb.2014.0119, PMID 24648228, PMC 3973276 (freier Volltext) – (englisch, royalsocietypublishing.org).
  10. ↑ a b Arne Redsted Rasmussen, John C. Murphy, Medy Ompi, J. Whitfield Gibbons, Peter Uetz: Marine Reptiles. In: PLoS ONE. 6. Jahrgang, Nr. 11, doi:10.1371/journal.pone.0027373, PMID 22087300, PMC 3210815 (freier Volltext) – (plos.org).
  11. ↑ Liptow, J. 1999. "Pelamis platurus" (On-line), Animal Diversity Web. Accessed June 23, 2007 at [1]
  12. ↑ Swimmers told not to be surprised of poisonous sea snake In: Waikato Times, Fairfax New Zealand, 4 January 2012. Abgerufen im 26 April 2012 
  13. ↑ Natural History Information Centre, Auckland War Memorial Museum: Natural History Questions. In: Auckland War Memorial Museum | Tamaki Paenga Hira. Auckland War Memorial Museum, abgerufen am 26. April 2012 (Q. Are there any snakes in New Zealand?).
  14. ↑ Also see references in The Living Shores of Southern Africa, Margo and George Branch, Page 130 - 131, Macmillan South Africa (Publishers), Johannesburg and "Snake versus Man" Johan Marais, page 50 - 51, C. Struik Publishers, Cape Town.
  15. ↑ (Dunson and Ehlert 1971).
  16. ↑ Blame El Niño for poisonous sea snake found on Ventura County beach. In: latimes.com. Abgerufen am 25. Oktober 2015.
  17. ↑ El Nino brings sea snake to California's coast - CNN.com. In: CNN. Abgerufen am 25. Oktober 2015.
  18. ↑ Coleman M. Sheehy, Alejandro Solórzano, Joseph B. Pfaller, Harvey B. Lillywhite: Preliminary insights into the phylogeography of the yellow-bellied sea snake, Pelamis platurus. In: Integrative and Comparative Biology. 52. Jahrgang, Nr. 2, 1. August 2012, ISSN 1557-7023, S. 321–330, doi:10.1093/icb/ics088, PMID 22659201 (nih.gov).
  19. ↑ Vimoksalehi Lukoschek, J. Scott Keogh: Molecular phylogeny of sea snakes reveals a rapidly diverged adaptive radiation. In: Biological Journal of the Linnean Society. 89. Jahrgang, Nr. 3, 1. November 2006, ISSN 1095-8312, S. 523–539, doi:10.1111/j.1095-8312.2006.00691.x (englisch, wiley.com).
  20. ↑ R. Alexander Pyron, Frank T. Burbrink, Guarino R. Colli, Adrian Nieto Montes de Oca, Laurie J. Vitt, Caitlin A. Kuczynski, John J. Wiens: The phylogeny of advanced snakes (Colubroidea), with discovery of a new subfamily and comparison of support methods for likelihood trees. In: Molecular Phylogenetics and Evolution. 58. Jahrgang, Nr. 2, 1. Februar 2011, ISSN 1095-9513, S. 329–342, doi:10.1016/j.ympev.2010.11.006, PMID 21074626 (nih.gov).
  21. ↑ Kate L. Sanders, Michael S. Y. Lee, Mumpuni, Terry Bertozzi, Arne R. Rasmussen: Multilocus phylogeny and recent rapid radiation of the viviparous sea snakes (Elapidae: Hydrophiinae). In: Molecular Phylogenetics and Evolution. 66. Jahrgang, Nr. 3, 1. März 2013, S. 575–591, doi:10.1016/j.ympev.2012.09.021 (sciencedirect.com).
  22. ↑ Kate L. Sanders, Arne R. Rasmussen, Johan Elmberg: Independent Innovation in the Evolution of Paddle-Shaped Tails in Viviparous Sea Snakes (Elapidae: Hydrophiinae). In: Integrative and Comparative Biology. 52. Jahrgang, Nr. 2, 1. August 2012, ISSN 1540-7063, S. 311–320, doi:10.1093/icb/ics066, PMID 22634358 (englisch, oxfordjournals.org).
  23. ↑ a b , R. Shine: The origin of evolutionary innovations: locomotor consequences of tail shape in aquatic snakes. In: Functional Ecology. 22. Jahrgang, Nr. 2, 1. April 2008, ISSN 1365-2435, S. 317–322, doi:10.1111/j.1365-2435.2007.01359.x (englisch, wiley.com).
  24. ↑ Roger S. Seymour: How sea snakes may avoid the bends. In: Nature. 250. Jahrgang, Nr. 5466, 9. August 1974, S. 489–490, doi:10.1038/250489a0 (englisch, nature.com).
  25. ↑ CSL Antivenom Handbook – Sea Snake Antivenom
  26. ↑ Arne Redsted Rasmussen, Kate Laura Sanders, Michael L. Guinea, Andrew P. Amey: Sea snakes in Australian waters (Serpentes: subfamilies Hydrophiinae and Laticaudinae)-a review with an updated identification key. In: Zootaxa. 3869. Jahrgang, 1. Januar 2014, ISSN 1175-5334, S. 351–371, PMID 25283923 (nih.gov).
  27. ↑ Tropical zoology 13:327–329, 2000, The gender of the genera ... Pelamis Daudin 1803 (hydrophiidae) B Lanza and S, Boscherini – Accessed online May, 2008
  28. ↑ Vorlage:NRDB species. Accessed May 2008
  29. ↑ SnakeBiteTemplate3.pmd
  30. ↑ LD50 value of venomous snakes
  31. ↑ [2] LD stands for "Lethal dose".
  32. ↑ https://www.flyingdoctor.net/IgnitionSuite/uploads/docs/snakebite.pdf Management of snake bites in Australia and Papua New Guinea. Accessed May 2008
  33. ↑ http://www.emedicine.com/emerg/topic543.htm Accessed May 2008
  34. ↑ http://www.ajtmh.org/cgi/content/abstract/23/1/135 Published 1973. Accessed May 2008.
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