Inland taipan: Difference between revisions
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{{Taxobox |
{{Taxobox |
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| name = Inland taipan (fierce snake) |
| name = Inland taipan (fierce snake) |
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| status = |
| status = |
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| status_system = |
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| image = Fierce Snake-Oxyuranus microlepidotus.jpg | |
| image = Fierce Snake-Oxyuranus microlepidotus.jpg | Fierce Snake at [[Australia Zoo]] |
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| image_width = 250px |
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| image_caption = ''Oxyuranus microlepidotus'' at [[Australia Zoo]] |
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| regnum = [[Animal]]ia |
| regnum = [[Animal]]ia |
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| phylum = [[Chordate|Chordata]] |
| phylum = [[Chordate|Chordata]] |
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| range_map = Fierce Snake Range.jpg |
| range_map = Fierce Snake Range.jpg |
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| range_map_caption = Range of inland taipan (in red) |
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| range_map_caption = General range of inland taipan (in red). The current, documented range of the species is more limited<ref name= "Animals of Queensland">Animals of Queensland. [http://www.qm.qld.gov.au/Find+out+about/Animals+of+Queensland/Reptiles/Snakes/Common+and+dangerous+species/Western+Taipan Western Taipan ''Oxyuranus microlepidotus'']. [[Queensland Museum]]. Retrieved November 8, 2013.</ref><ref name= "Australian Reptile Online Database">Australian Reptile Online Database (28 March 2007). [http://www.arod.com.au/arod/reptilia/Squamata/Elapidae/Oxyuranus/microlepidotus?tab=distribution Inland taipan distribution]. arod.com.au. Retrieved November 8, 2013.</ref><ref name= "Atlas of Living Australia 1">[http://bie.ala.org.au/species/Inland+Taipan ''Oxyuranus microlepidotus'' (McCoy, 1879) Western Taipan]. [[Atlas of Living Australia]]. Retrieved November 8, 2013.</ref> |
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| synonyms = *''Diemenia microlepidota'' |
| synonyms = *''Diemenia microlepidota'' <small>F. McCoy, 1879</small> |
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*'' |
*''Pseudechis microlepidotus'' <br><small>— [[George Albert Boulenger|Boulenger]], 1896</small> |
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*'' |
*''Parademansia microlepidota'' <br><small>— [[:fr:James Roy Kinghorn|Kinghorn]], 1955</small> |
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*''Oxyuranus microlepidotus'' <br><small>— Covacevich et al., 1981<ref>The Reptile Database. www.reptile-database.org.</ref> |
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*''Parademansia microlepidota'' <br><small>— [[:fr:James Roy Kinghorn|Kinghorn]], 1955</small> |
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*''Oxyuranus scutellatus microlepidotus'' <br><small>— [[Eric Worrell|Worrell]], 1963 </small> |
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*''Oxyuranus microlepidotus'' <br><small>— [[Jeanette Covacevich|Covacevich]] et al., 1981</small><ref name= "Fohlman, J"/> |
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}} |
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The '''inland taipan''' '''''(Oxyuranus microlepidotus)''''', also commonly known as the '''small-scaled snake''' and '''fierce snake''', is a [[species]] native to [[Australia]] and is regarded as the most [[venomous]] land snake in the world based on [[LD50|LD<sub>50</sub>]] values in [[mice]].<ref>[http://seanthomas.net/oldsite/ld50tot.html LD50], seanthomas.net (December 1999).</ref> It is a species of [[taipan]] belonging to the [[Elapidae]] family. Although highly venomous, it is very shy and reclusive, and always prefers to escape from threat (the word "fierce" from its alternative name describes its venom, not its temperament).<ref>{{cite web|url=http://www.australiazoo.com.au/our-animals/amazing-animals/reptiles/?reptile=venomous_snakes&animal=fierce%20snake|title=Our Animals – Reptiles – Venomous Snakes – Fierce Snake|publisher=Australia Zoo|accessdate=2009-05-21}}</ref> |
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The '''inland taipan''' ('''''Oxyuranus microlepidotus'''''), also commonly known as the '''western taipan''', the '''small-scaled snake''', or the '''fierce snake''',<ref name= "INCHEM">White, Julian (November 1991). [http://www.inchem.org/documents/pims/animal/taipan.htm ''Oxyuranus microlepidotus''] . "Neurotoxic paralysis usually takes 2-4 hours to become clinically detectable. Coagulopathy however may become well established within 30 minutes of a bite" [[International Programme on Chemical Safety]]. Retrieved November 8, 2013.</ref> is a highly [[venomous snake]] of the [[taipan]] (''Oxyuranus'') [[genus]], and is [[Endemism|endemic]] to [[semi-arid]] regions of central east [[Australia]].<ref name="ANIMAL SPECIES:Inland Taipan"/> [[Aboriginal Australians]] living in those regions named the snake ''Dandarabilla''.<ref name= "History & Discovery">Queensland Snakes . [http://web.archive.org/web/20090613091835/http://www.qm.qld.gov.au/features/snakes/taipan/discovery.asp History & Discovery]. (archived) [[Queensland Museum]]. Retrieved November 15, 2013.</ref> It was first described by [[Frederick McCoy]] in 1879 and then by [[William John Macleay]] in 1882, but for the next 90 years, it was a mystery [[species]] to [[Western Science]]. No more [[wikt:specimen|specimen]]s were found, and virtually nothing was added to [[knowledge]] of this species until its rediscovery in 1972.<ref name="History & Discovery" /><ref name="Rediscovery" /> |
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==Appearance== |
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Its [[Snake venom|venom]], drop for drop, is by far the most [[Toxicity|toxic]] of any snake in the world – much more so than even [[Sea Snake|sea snakes]].<ref name="ANIMAL SPECIES:Inland Taipan">Cecilie Beatson (November 29, 2011). [http://australianmuseum.net.au/Inland-Taipan ANIMAL SPECIES:Inland Taipan] "The venom of the Inland Taipan is extremely potent and is rated as the most toxic of all snake venoms in LD50 tests on mice". [[Australian Museum]]. Retrieved October 14, 2013.</ref><ref name="avru.org">The Australian venom research unit (August 25, 2007). [http://www.avru.org/compendium/biogs/A000084b.htm "Which snakes are the most venomous?"]. [[University of Melbourne]]. Retrieved October 14, 2013.</ref><ref name="viper.arizona.edu">Venom Immunochemistry, Pharmacology and Emergency Response (VIPER) Institute. [http://viper.arizona.edu/faq/what-most-venomous-snake Frequently Asked Questions -What is the most venomous snake?]. "Many experts answer that it is the Inland Taipan of Australia, because its drop-by-drop concentration of venom has great potency when measured by its ability to kill rodents" . [[University of Arizona]]. Retrieved October 14, 2013.</ref><ref name= "Department of Wildlife Ecology and Conservation">Department of Wildlife Ecology and Conservation. [http://ufwildlife.ifas.ufl.edu/venomous_snake_faqs.shtml Frequently Asked Questions About Venomous Snakes]. "A comparative study found that the snake venom that is most toxic to mice (of the species tested) is that of the Inland Taipan (''Oxyuranus microlepidotus''), found in Australia". [[University of Florida]]. Retrieved November 5, 2013.</ref><ref name="Hodgson et al 2007">{{cite journal|author=Hodgson WC, Dal Belo CA, Rowan EG |pmid=17313963 |title=The neuromuscular activity of paradoxin: a presynaptic neurotoxin from the venom of the inland taipan (''Oxyuranus microlepidotus'')|quote=The inland taipan is the world's most venomous snake |year=2007 |volume=52 |issue=5 |pages=1229–36 |doi=10.1016/j.neuropharm.2007.01.002 |journal=Neuropharmacology}}</ref><ref name="Bell KL 1998">{{cite journal |doi=10.1016/S0041-0101(97)00060-3 |title=Some pharmacological studies of venom from the inland taipan (''Oxyuranus microlepidotus'') |quote=The Inland Taipan is believed to have the most toxic venom in the world (Sutherland, 1994) |year=1998 |last1=Bell |first1=Karen L |last2=[[Struan Sutherland|Sutherland]] |first2=Struan K |last3=Hodgson |first3=Wayne C |journal=Toxicon |volume=36 |pages=63–74 |pmid=9604283 |issue=1}}</ref><ref name= "9 of the World's Deadliest Snakes">LISTS . [http://www.britannica.com/list/10/1/1-the-snake-with-the-worlds-deadliest-venom Nine of the World's Deadliest Snakes]. "#1: The snake with the world's deadliest venom - ''Oxyuranus microlepidotus''" . [[Encyclopædia Britannica]]. Retrieved November 5, 2013.</ref><ref name="Inland Taipan page">BBC Nature Wildlife. [http://www.bbc.co.uk/nature/life/Inland_Taipan Inland Taipan page]. "Australia's inland taipan is considered to be the most venomous snake in the world". [[BBC]]. Retrieved October 15, 2013.</ref><ref name="[[Steve Irwin]] presentation">[[Steve Irwin]] presentation .[http://www.youtube.com/watch?v=mlDXZywedvc&feature=youtu.be&t=1m54s Australia Zoo Tour with Steve Irwin] (1m54s) "..the number 1 most venomous snake in the entire world, the fierce snake". [[Australia Zoo]] (official Youtube Channel). Retrieved October 14, 2013.</ref><ref name="science.org.au">Oakley, Cecily (2011). [http://science.org.au/scientists/interviews/f/fry.html Interview with Associate Professor Bryan Fry Biochemist and molecular biologist]. "...For my PhD, I worked on the inland taipan, which is the world’s most venomous snake..." . [[Australian Academy of Science]]. Retrieved October 14, 2013.</ref><ref name="Journal of Herpetology Vol.17" /><ref name="Dr. Bryan Grieg Fry - Interview">Inland Taipan Venom vs. Sea Snakes Venom (most notable [[Belcher's sea snake]]) |
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The inland taipan is dark tan, ranging from a rich, dark hue to a brownish light-green, depending on season. Its back, sides and tail may be different shades of brown and grey, with many scales having a wide blackish edge. These dark-marked scales occur in diagonal rows so that the marks align to form broken chevrons of variable length that are inclined backward and downward. The lowermost lateral scales often have an anterior yellow edge. The dorsal scales are smooth and without keels. The round-snouted head and neck are usually noticeably darker than the body (glossy black in winter, dark brown in summer), the darker colour allowing the snake to heat itself while only exposing a smaller portion of the body at the burrow entrance. The eye is of average size with a blackish brown iris and without a noticeable coloured rim around the pupil. |
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* kingsnake.com September Guest Chatter (September 16, 2006).[http://www.connectedbypets.com/articles/BGF.html Q&A with Dr. Bryan Grieg Fry, Deputy Director, Australian Venom Research Unit, University of Melbourne]. "Q: In retrospect to the LD50 charts, what do you personally feel is the hottest snake, in regards to potency, defensiveness, means of injection, etc.? A: It is the inland taipan (''Oxyuranus microlepidotus''). Not, as is popularised, any of the sea snakes." connectedbypets.com. Retrieved October 14, 2013. |
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* Garden of Eden Exotics (May 2, 2012) [http://nyexotics.blogspot.co.il/2012/05/dr-bryan-grieg-fry-venom-useless-pickup.html Dr. Bryan Grieg Fry – Interview] "...The inland taipan (''Oxyuranus microlepidotus') is far and away the most toxic, much more so than even sea snakes." nyexotics.blogspot.com Retrieved October 14, 2013</ref> Unlike [[Snake#Feeding and diet|most snakes]], the inland taipan is a specialist [[mammal]] [[Predation|hunter]] so its venom is specially adapted to kill [[warm-blooded|warm-blooded species]].<ref name="abc.net.au">Shorter, Damon. [http://www.abc.net.au/science/slab/shorter/story.htm Great Australian bites – Three of the worst]. [[Australian Broadcasting Corporation]]. Retrieved October 16, 2013.</ref><ref name="venomsupplies.com">[http://www.venomsupplies.com/inland-taipan/ Inland Taipan ''Oxyuranus microlepidotus'']. venomsupplies.com. Retrieved October 18, 2013.</ref> It is estimated that one bite possesses enough [[lethality]] to kill at least 100 full grown men,<ref name= "Journal of Herpetology Vol.17" >Journal of Herpetology Vol.17 no.1 (1983) [http://sydney.edu.au/science/biology/shine/publications/reprints_legal/33taipanecology.pdf Ecology of Highly Venoumous Snakes: the Australian Genus ''Oxyuranus'']. "..the number of mouse LD50 doses per bite is much higher for ''Oxyuranus'' microlepidotus (218,000 mice)...than for any other snakes, including sea snakes, investigated to date (Broad, Sutherland and Coulter, 1979)." (page 1) [[University of Sydney]]. Retrieved November 8, 2013.</ref><ref name="REPTILES - FIERCE SNAKE">[http://www.australiazoo.com.au/our-animals/amazing-animals/reptiles/?animal=fierce_snake&reptile=venomous_snakes "REPTILES – FIERCE SNAKE"] . [[Australia Zoo]]. Retrieved October 14, 2013.</ref><ref name="Newsletter No.80">Martin, Stella (January 2004). [http://www.wettropics.gov.au/site/user-assets/docs/80VeryVenomousBut.pdf Newsletter No. 80]. "It has been calculated that there is enough venom in just one bite of an Inland taipan to kill more than 100 men of average size." [[Environmental Protection Agency (Queensland)]]. Retrieved October 18, 2013.</ref><ref name="newsfeed.time.com"/> and, depending on the nature of the bite, can kill someone in as little as 30 to 45 minutes if left untreated.<ref name= "INCHEM"/><ref name="toxicology.ucsd.edu">Devision of Medical Toxicology. [http://toxicology.ucsd.edu/Snakebite%20Protocols/Oxyura~1.htm "Summary for Human Bite by Inland Taipan (''Oxyuranus microlepidotus'')"]. [[University of California, San Diego]]. Retrieved October 15, 2013.</ref><ref name="smh.com.au">Gardiner, Stephanie (September 27, 2012). [http://www.smh.com.au/nsw/mystery-over-boy-bitten-by-worlds-most-venomous-snake-20120927-26may.html "Mystery over boy bitten by world's most venomous snake "]. (Quoting Julie Mendezona, Head keeper of Reptiles and Spiders, [[Australian Reptile Park]]) [[The Sydney Morning Herald]]. Retrieved October 14, 2013.</ref><ref name="australiantimes.co.uk">News from Australia (September 27, 2012). [http://www.australiantimes.co.uk/news/news-from-australia/news-in-australia/deadly-taipan-snake-may-have-been-a-pet-catcher.htm Deadly Taipan snake may have been a pet: catcher]. (Quoting licensed reptile handler, [http://www.environment.nsw.gov.au/resources/wildlifelicences/reptilehandlerlist.pdf Barry Martin]) australiantimes.co.uk. Retrieved October 18, 2013.</ref> It is an extremely fast and [[Agility|agile]] snake which can [[Strike (attack)|strike]] instantly with extreme accuracy,<ref name="newsfeed.time.com"/><ref name="Fox San Antonio 1"/><ref name="ReferenceA"/> often snapping its jaws fiercely several times to inflict multiple [[Penetrating trauma|punctures]] in the same attack.<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="ReferenceA">Clinical Toxinology Resources. [http://toxicology.ucsd.edu/Snakebite%20Protocols/Oxyura~1.htm Snakebite Protocols – ''Oxyuranus microlepidotus'']. "'''Signs and Symptoms of Envenomation:''' ''E. Fang Marks:'' The snake strikes with extraordinary speed and accuracy, often snapping its jaws fiercely several times which can result in multiple punctures in the same attack.", "'''Special Considerations:''' ''A. Multiple Bites:'' The Inland Taipan is an extremely fast and agile snake which can strike instantly with extreme accuracy. It is possible for a Taipan to deliver more than one bite in a single attack." [[University of Adelaide]]. Retrieved October 18, 2013.</ref> |
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It has 23 rows of [[dorsal scales]] at midbody, between 55 and 70 divided [[subcaudal scales]], and one [[anal scale]]. |
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Although highly venomous and a capable striker, contrary to the rather aggressive natured<ref name="abc.net.au"/> [[coastal taipan]], the inland taipan is usually quite a shy and [[reclusive]] snake, with a [[wikt:placid|placid]] [[disposition]],<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="saalnrm.sa.gov.au">South Australia arid lands natural resorces managment board. [http://www.saalnrm.sa.gov.au/Portals/8/Publications_Resources/Factsheets_Brochures/SAAL-Woma_Python_Inland_Taipan-FS-STD-122009.pdf Biodiversity studies, Student fact sheet]. [[Government of South Australia]]. Retrieved October 15, 2013.</ref><ref name="toxinology.com">Clinical Toxinology Resources. [http://www.toxinology.com/fusebox.cfm?fuseaction=main.snakes.display&id=SN0520 "''Oxyuranus microlepidotus'' -General Details, Taxonomy and Biology, Venom, Clinical Effects, Treatment, First Aid , Antivenoms"]. [[University of Adelaide]]. Retrieved October 14, 2013.</ref><ref name="Judith {Judy} Martin"/> and prefers to escape from trouble.<ref name="newsfeed.time.com">Carbone, Nick reporting on [[Steve Irwin]] (September 04, 2011). [http://newsfeed.time.com/2011/09/04/remembering-steve-irwin-the-5-most-memorable-crocodile-hunter-videos/ Remembering Steve Irwin: The 5 Most Memorable Crocodile Hunter Videos] "Steve Irwin Plays with Inland Taipan (Fierce Snake)". [[Time (magazine)]]. Retrieved October 15, 2013.</ref><ref name="Fierce Snake - profile">Threatened species October 10, 2012. [http://www.environment.nsw.gov.au/threatenedSpeciesApp/profile.aspx?id=20169 Fierce Snake – profile]. [[Office of Environment and Heritage (New South Wales)]]. Retrieved October 15, 2013.</ref> However, it will defend itself and strike if provoked,<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="Fox San Antonio 1"/><ref name= "Steve Backshall 2">[[Steve Backshall]] (May 19, 2013) film clip. [http://www.youtube.com/watch?v=7N-ZlwETll0 The most venemous snake on earth! - Deadly 60 - BBC]. [[BBC Earth]] (official YouTube channel). Retrieved November 14, 2013.</ref> mishandled,<ref name="Judith {Judy} Martin">ABC News 24 (September 28, 2012) . [http://www.abc.net.au/news/2012-09-28/taipan-mystery/4285224 'Placid' taipan in safe hands]. (Quoting licensed reptile handler, [http://www.environment.nsw.gov.au/resources/wildlifelicences/reptilehandlerlist.pdf Judith {Judy} Martin]) . [[Australian Broadcasting Corporation]]. Retrieved November 13, 2013.</ref> or prevented from escaping.<ref name="newsfeed.time.com"/> Also because it lives in such remote locations, the inland taipan seldom comes in contact with people;<ref name="billabongsanctuary.com.au">Aussie Animals.[http://www.billabongsanctuary.com.au/aussie_animals/inland_taipan.html Inland Taipan (Oxyuranus microlepidotus)]. [[Billabong Sanctuary]]. Retrieved October 18, 2013.</ref> therefore it is not considered the [[Snakebite#Snakes of particular concern|most deadly snake in the world]] overall, especially in terms of disposition and human deaths per year.<ref name= "World's Deadliest Snakes">Venomous Snakes. [http://www.reptilegardens.com/reptiles/snakes/venomous/worlds-deadliest-snakes.php World's Deadliest Snakes – Ranking scale]. [[Reptile Gardens]]. Retrieved October 18, 2013.</ref><ref>Walls, Jerry G. . [http://www.reptilechannel.com/snakes/venomous-snakes/deadly-snakes.aspx Deadly Snakes: What are the world's most deadly venomous snakes?]. [[Reptiles (magazine)]]. Retrieved November 5, 2013.</ref><ref>[[National Geographic Channel]], (Dangerous Encounters with [[Brady Barr]]), video clip. [http://www.reptilegardens.com/about-us/media-attention.php#movie-clips Deadliest Snakes / Inland Taipan] "in Deadliest Snakes, Brady approaches seven of the world's most dangerous and venomous snakes to determine which snake is the deadliest. He will scientifically investigate each species of snake by grading them on five basic criteria: size, volume and toxicity of venom, personality, and number of human deaths." [[Reptile Gardens]] (video host). Retrieved November 6, 2013.</ref> The word "fierce" from its alternative name describes its venom, not its temperament.<ref name="Fierce Snake - profile"/> |
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The inland taipan averages approximately {{convert|1.8|m|ft}} in total length, although larger specimens can reach total lengths of {{convert|2.5|m|ft}}.<ref>{{cite web|url=http://www.reptilepark.com.au/animals.asp?catID=16&ID=112|title=Fierce Snake (Inland Taipan)|publisher=Australian Reptile Park|accessdate=2009-11-07}}</ref> |
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==Etymology== |
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''Oxyuranus microlepidotus'' has been the fierce snake's [[Binomial nomenclature|binomial name]] since the early 1980s.<ref name= "Two Taipans">Two Taipans. [http://web.archive.org/web/20090615141619/http://www.qm.qld.gov.au/features/snakes/taipan/two.asp Two Taipans - Coastal and Western]. (archived) [[Queensland Museum]]. Retrieved November 15, 2013.</ref><ref name= "Covacevich, J">Covacevich, J., McDowell, S.B., Tanner, C. & Mengdon, G. (Aust. Herp. Symposium, 1980). [http://www.kingsnake.com/aho/pdf/menu2/covacevich1981.pdf The relationship of the taipan (''Oxyuranus scutellatus'') and the small-scaled snake (''O. microlepidotus''), Serpentes: Elapidae] (page 32). kingsnake.com Retrieved November 15, 2013</ref> The [[Genus|generic]] name, ''Oxyuranus'', means ''oxus'' ([[Ancient Greek|Greek]]) "sharp pointed", ''oura'' (Greek) "tail"; ''-anus'' ([[Latin]]) |
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"belonging to", and refers to the inland taipan's long pointed tail. The [[Specific name (zoology)|specific name]], ''microlepidotus'', means "small-[[Reptile scale|scaled]]" (Latin). Hence the common name, small-scaled snake.<ref name= "Welton, Ronelle Ellen"/> Since it has been determined (Covacevich et al., 1981) that the fierce snake (formerly: ''Parademansia microlepidota'') is actually part of the genus ''[[Oxyuranus]]'' (taipan), another species, ''Oxyuranus scutellatus'', which was previously commonly named taipan (coined from the [[Aboriginal Australians|aboriginal]] snake's name ''Dhayban'') became coastal taipan (or eastern taipan), and the now newly classified ''Oxyuranus microlepidotus'', became commonly known as inland taipan (or western taipan).<ref name= "Rediscovery">Rediscovery. [http://web.archive.org/web/20090613092123/http://www.qm.qld.gov.au/features/snakes/taipan/rediscovery.asp The Rediscovery of the Western Taipan]. (archived) [[Queensland Museum]]. Retrieved November 15, 2013.</ref> The word "fierce" from its alternative name, fierce snake, describes its powerful venom.<ref name="Fierce Snake - profile"/> |
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===Seasonal adaptation=== |
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==History== |
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Inland taipans adapt to their environment by changing the colour of the skin during seasonal changes. They tend to become lighter during summer and darker during the winter. This seasonal colour change serves the purpose of thermoregulation, allowing the snake to absorb more light in the colder months. |
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===Evolution=== |
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Two Australian taipans (the [[coastal taipan]], ''Oxyuranus scutellatus'', and the inland taipan, ''Oxyuranus microlepidotus'') shared a [[Common descent|common ancestor]]. Alignments of the [[mitochondrial]] [[MT-ND4|ND4 genes]] from the inland taipan and the coastal taipan found variations of approximately 13%. This indicates an [[Speciation|evolutionary divergence]] from a common ancestor around 9-10 million years ago. Based on the current understanding of the [[phylogenetic]] relationships of [[Australia|Australo]]-[[New Guinea|papuan]] venomous snakes, it has been suggested that the [[Morphology (biology)|morphological]] diversity and innovation seen in taipan (''[[Oxyuranus]]'') species might be traceable to a ''[[Pseudonaja]]''-like ancestor (Scanlon, et al., 2003). The inland taipan has retained many physiological and behavioural traits resembling present-day ''Pseudonaja'' species, such as small head size, short [[fangs]], lower [[venom]] yields, high toxicity, and distinctive threat posture. However, ''Pseudonaja'' species are opportunistic feeders and pursue a range of small prey animals, whereas the inland taipan has diverged to hunt moderately sized [[mammals]] such as the plague rat (''[[Rattus villosissimus]]'') in the confined spaces of narrow earth cracks and animal [[burrow]]s. In contrast other taipan species have developed several recently derived, innovative features: larger head, larger eyes and jaw gape, large fangs, large venom yields, high toxicity, larger body size, and a unique "snap and release" biting strategy. These innovations have been attributed to diet and [[foraging]] behaviour (Shine, 1983)<ref name= "Welton, Ronelle Ellen"/> |
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=== Prehistory === |
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Both the Inland and Costal taipans would have been known to [[Aboriginal Australians]] 40,000-60,000 years ago and both are well known to them today.<ref name="History & Discovery" /> To the Aboriginal people from the place now called [[Goyder Lagoon]], north-east [[South Australia]], '''Dandarabilla''' was the snake now known as the Inland taipan. To the [[Wik Mungkan language|Wik-munkan]] People from western [[Cape York Peninsula]], [[Far North Queensland]], '''Dhayban'''<ref name= "Merriam-Webster 1">2tai·pan. [http://www.merriam-webster.com/dictionary/taipan Origin of TAIPAN]. (archived) [[Merriam-Webster]]. Retrieved November 15, 2013.</ref> was the snake now known as the Coastal taipan.<ref name="History & Discovery" /> (from them, Anthropologist [[Donald Thomson]], coined the snake's English common name, Taipan).<ref>Sutton, Peter. ''Wik Ngathan Dictionary,'' 1995.</ref> |
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{{quotation|''"… [the] power of destruction has made Dhayban the arbiter of life and death. If he points a bone, a man dies. But he can also cure, for … he … controls the blood supply, the loss of which causes death…. He … gave blood to mankind, and … wields power over the physiological processes of men and women …. He is the great physician."''<br /> |
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<br /> |
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''"An old lady was coming up Goyder's Lagoon way. She met an old man who had with him some snakes in a bag. He gave her the bag in exchange for some strings made of hair. The bag was not tied up properly and her little boy, who was being carried in a hair shoulder bag, was bitten by a snake. The old lady knew that the little boy should have cried to be fed because he would be hungry for the breast around lunch-time, but he didn't. The old lady looked in the bag and found he was dead, poor little fella....'' |
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''...She came from Mount Gayson. She came past Toowell, past Putabutna. Went straight pass Kulpitaboolta, got to Yapawarrilina, and that's where she buried her little boy, then she came down to lagoon waterhole. She started to collect wood and cry at the same time, when a needle bush poked in the eye. She was blind for awhile. She then went home to Duck Egg Sandhill where she left some duck eggs. She flew back to lagoon waterhole where she tipped all the snakes out on the ground. She went back to Coongie and stayed there until her death."''|Aboriginal stories recording both species<ref name="History & Discovery" />}} |
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===Scientific discovery=== |
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The first inland taipan to come to the attention of [[Western Science]] was in 1879. Two specimens<ref name="Rediscovery"/> of the fierce snake were first discovered in the junction of the [[Murray River|Murray]] and [[Darling River]]s in northwestern [[Victoria (Australia)|Victoria]] and described by [[Frederick McCoy]], who called the species ''Diemenia microlepidota'', or small-[[Reptile scale|scaled]] [[Pseudonaja|brown snake]]. In 1882 a third specimen was found near [[Bourke, New South Wales|Bourke]], [[New South Wales]], and [[William John Macleay]] described the same snake under the name ''Diemenia ferox'' (thinking is was a different species<ref name= "Kinghorn, J. Roy"/>).<ref name= "Fohlman, J"/><ref name="ANIMAL SPECIES:Inland Taipan"/> In 1896 [[George Albert Boulenger]] classified both as belonging to the same [[genus]], [[Pseudechis]] (Black Snakes), referring them as ''Pseudechis microlepidotus'' and ''Pseudechis ferox''.<ref name= "Fohlman, J"/> |
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For the next 90 years virtually nothing would be added to knowledge of this species. It was, for practical purposes, "lost". No more specimens were discovered. No information on its occurrence, behaviour, or venom properties was published.<ref name="History & Discovery" /> |
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In 1956, relying only on published descriptions and notes,<ref name= "Kinghorn, J. Roy">Kinghorn, J. Roy (September 1, 1955). [http://australianmuseum.net.au/Uploads/Journals/17387/638_complete.pdf Herpetological notes. No. 5] (page 284). [[Australian Museum]] Scientific Publications, Retrieved November 14, 2013</ref> [[:fr:James Roy Kinghorn|James Roy Kinghorn]] regarded ''ferox'' as a [[synonym]] for ''microlepidotus'' and proposed the [[genus]] ''Parademansia''. In 1963 [[Eric Worrell]] considered ''Parademansia microlepidotus'' and ''[[Oxyuranus scutellatus]]'' (coastal taipan, named simply "taipan" in those days) to be the same [[species]]. .<ref name= "Fohlman, J"/> |
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====Rediscovery==== |
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When a tour operator was bitten by a large, dark brown, black-headed snake in far southwestern [[Queensland]] in 1967, the effects of the snake's venom were devastating. The [[Royal Flying Doctor]] and a specialist in [[Adelaide]] saved his life. The snake responsible was identified by the victim as a [[Pseudonaja nuchalis|Western Brown snake]] (Pseudonaja nuchalis). Later, the specimen was examined further and identified as a taipan (Coastal taipan today), ''Oxyuranus scutellatus''. This specimen was re-examined subsequent to the rediscovery, in 1972, of the snake by then known as ''Parademansia microlepidota''. That comparison showed they were the same species.<ref name="Rediscovery" /> |
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In August 1972, [[Herpetologist]] [[Australian Natural History Medallion|Jeanette Covacevich]], formerly of the [[Queensland Museum]] received in the mail a tin can from a Mr. Herb Rabig, a [[grazier]] from one of the [[Channel Country]] stations west of [[Windorah]]. The tin contained the preserved head and tail of a snake she had not seen before. She attempted to identify it routinely and could not make a 'fit' with anything in the readily available [[literature]]. A check of the [[taxonomic]] [[Academic journal|journal]] literature and an early review of the [[fauna]] of [[Victoria (Australia)|Victoria]] confirmed that, on her desk, sat a specimen of an [[elapid]] snake described in 1879 as ''Diemenia microlepidota'' from only two specimens. Only one other had been found (1882) and it had been lost very soon after its discovery. Probably, because no more specimens had been found and there was no way of knowing where to search, ''Diemenia microlepidota'' had virtually disappeared from both the taxonomic literature and guides to [[Snakes of Australia|Australia's snakes]]. ''Parademansia microlepidota'' continued to be a "missing", mystery species.<ref name="Rediscovery" /> |
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Following Herb Rabig's donation of the head and tail of a freshly collected ''Parademansia microlepidota'', a field trip was planned (funded by the Queensland Museum) with Jeanette Covacevich and Charles Tanner, an eminent herpetologist, to find this snake. The quest was to find live specimens for venom studies and to try and uncover some information about the behaviour of ''Parademansia microlepidota''. In September 1972, they travelled to the [[Channel Country]] of the far southwest Queensland.<ref name="Rediscovery" /> In the following 10 days, with the help and advice of Herb Rabig, they found 13 healthy, live specimens, all of which were brought back to the Queensland Museum for future study. Then began 12 years of research, both at the Museum and with colleagues, specialists in [[taxonomy]], [[toxinology]] and [[ecology]], from Australia and abroad.<ref name="Rediscovery"/> |
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In 1976 Jeanette Covacevich and John Wombey argued that ''Parademansia microlepidotus'' belongs to a distinct genus, and this was also the opinion of [[Harold Cogger]].<ref name= "Fohlman, J">{{cite journal |doi=10.1016/0041-0101(79)90296-4 |title=Comparison of two highly toxic Australian snake venoms: The taipan (''Oxyuranus s. scutellatus'') and the fierce snake (Parademansia microlepidotus) |year=1979 |last1=Fohlman |first1=J. |journal=Toxicon |volume=17 |issue=2 |pages=170–2 |pmid=442105}}</ref> |
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In 1981, examination of external features, facial muscles, skull measurements, [[venom]], [[hemipenis]] anatomy, numbers and shapes of [[chromosomes]], and behaviour of the two species then known as ''Oxyuranus scutellatus'' and ''Parademansia microlepidota'', showed they should be placed together in one [[genus]]. They were more closely related to each other than to any other [[species]]. ''[[Oxyuranus]]'' (1923), was the appropriate generic name for both species because it pre-dated ''Parademansia'' (1955). The work of Covacevich, McDowell, Tanner & Mengden (1981) led to the change.<ref name="Two Taipans" /> |
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==Geographic range== |
==Geographic range== |
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The inland taipan is native to the arid regions of central to eastern Australia. Its range extends from the southeast part of the [[Northern Territory]] into west [[Queensland]]. The snake can also be found north of [[Lake Eyre]] and to the west of the split of the [[Murray River]], [[Darling River]], and [[Murrumbidgee River]]. |
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The inland taipan inhabits the [[Vertisol|black soil]] [[plain]]s in the [[semi-arid]] regions where [[Queensland]] and [[South Australia]] borders converge.<ref name="ANIMAL SPECIES:Inland Taipan"/><ref>Threatened species (October 10, 2012. [http://www.environment.nsw.gov.au/threatenedSpeciesApp/profile.aspx?id=20169 Fierce Snake – profile]. [[Office of Environment and Heritage (New South Wales)]]. Retrieved October 16, 2013.</ref> |
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==Diet and behaviour== |
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In Queensland the snake has been observed in [[Channel Country]] region<ref name= "Wildlife of Channel Country (CHC) bioregion">[http://wetlandinfo.ehp.qld.gov.au/wetlands/facts-maps/wildlife/?AreaID=bioregion-channel-country-chc Wildlife of Channel Country (CHC) bioregion]. (western taipan) [[Department of Environment and Heritage Protection (Queensland)]]. Retrieved November 10, 2013.</ref> (e.g., [[Diamantina National Park]], [[Durrie Station]], [[Morney Plains Station]]<ref name= "Desert Channels region">Desert Channels region Natural resource management. [http://www.dcq.org.au/sites/default/files/Biodiversity%20plan%20part2.pdf Desert Channels Queensland’s Biodiversity Plan]. (Channel country, page 24 /special fauna areas) [[Government of Queensland]] . Retrieved November 10, 2013.</ref> and [[Astrebla Downs National Park]]<ref name= "Wildlife of Astrebla Downs National Park">[http://wetlandinfo.ehp.qld.gov.au/wetlands/facts-maps/wildlife/?AreaID=national-park-astrebla-downs Wildlife of Astrebla Downs National Park]. (western taipan) [[Department of Environment and Heritage Protection (Queensland)]]. Retrieved November 10, 2013.</ref>) and in South Australia it has been observed in the [[Marree, South Australia|Maree]]-[[Innamincka, South Australia|Innamincka]] [[Natural resource management|NRM]] District.<ref name= "tracks of the Marree Innamincka District">South Australia arid lands natural resources management board. [http://www.saalnrm.sa.gov.au/Portals/8/Publications_Resources/Factsheets_Brochures/saal_greattracks_062012.pdf Birdsville Strzelecki - Legendary tracks of the Marree Innamincka District]. (map of district on second page) (Inland taipan page 7) [[Government of South Australia]]. Retrieved November 10, 2013.</ref><ref name= "About the Marree–Innamincka District">South Australia arid lands natural resources management board. [http://www.saalnrm.sa.gov.au/AboutUs/OurNRMDistrictGroups/MarreeInnamincka.aspx Marree – Innamincka Natural Resources Management Group]. [[Government of South Australia]]. Retrieved November 10, 2013.</ref> (e.g., [[Goyder Lagoon]]<ref name= "muscle relaxant effects of venom">[[Toxicon]] journal (January 1999) [http://www.researchgate.net/publication/8077897_Novel_natriuretic_peptides_from_the_venom_of_the_inland_taipan_(Oxyuranus_microlepidotus)_isolation_chemical_and_biological_characterisation/file/d912f50d6fa548c2bf.pdf The smooth muscle relaxant effects of venom from the inland taipan (''Oxyuranus microlepidotus'')]. (page 1) [[ResearchGate]]. Retrieved November 10, 2013.</ref> [[Tirari Desert]], [[Sturt Stony Desert]], [[Coongie Lakes]], [[Innamincka Regional Reserve]] and [[Oodnadatta]]<ref name= "SAAL Regional Species Conservation Assessment"/>). An isolated population also occurs near [[Coober Pedy]], South Australia.<ref name= "Animals of Queensland"/><ref name= "Australian Reptile Online Database"/><ref name="saalnrm.sa.gov.au"/> |
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The inland taipan consumes mostly [[rodent]]s, other small [[mammal]]s, and [[bird]]s. Unlike other venomous snakes that strike with a single accurate bite then retreat to wait for the prey to die, the inland taipan is known to deliver up to seven venomous bites in a single attack. |
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==Reproduction== |
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There are two old records for localities further south-east, i.e., the junction of the [[Murray River|Murray]] and [[Darling River]]s in northwestern [[Victoria (Australia)|Victoria]] (1879) and [[Bourke, New South Wales|Bourke]], [[New South Wales]] (1882); however the species has not been collected in either state since then.<ref name= "Animals of Queensland"/><ref name="ANIMAL SPECIES:Inland Taipan"/> |
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Inland taipan produce clutches of between one and two dozen eggs. The eggs hatch two months later. The eggs are usually laid in abandoned animal burrows and deep crevices. Reproduction rate depends in part on their diet. If there is not enough food, then the snake will reproduce less. |
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===Habitat=== |
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Inland taipans are associated with the deep cracking-[[clays]] and cracking-[[loams]] of the [[floodplains]] to escape predators and the searing heat. However they also venture onto nearby [[Desert pavement|gibber plains]], [[dunes]] and [[Outcrop|rocky outcrops]] if cover is available. The vegetation in these areas is usually sparse, consisting of [[Chenopodioideae|chenopod shrubs]], [[Muehlenbeckia florulenta|lignum]] and the occasional [[eucalypt]] near the water channels.<ref name="ANIMAL SPECIES:Inland Taipan"/> |
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The snakes shelter in soil cracks and [[Fracture (geology)|crevices]], and in holes and [[mammal]] [[burrow]]s.<ref name="ANIMAL SPECIES:Inland Taipan"/> |
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===Conservation Status=== |
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Like every [[Snakes of Australia|Australian snake]], the inland taipan is protected by [[law]].<ref name="billabongsanctuary.com.au"/> |
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[[Conservation status]] has not yet been assessed for the [[IUCN Red List]] as of 8 November 2013.<ref name= "Red List search engine">[http://www.iucnredlist.org/search Red List search engine]. "''Oxyuranus microlepidotus'' - This taxon has not yet been assessed for the IUCN Red List" . [[IUCN Red List]]. Retrieved November 8, 2013.</ref> |
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The inland taipan's Conservation Status has been designated by Australian official sources:<ref name= "Threatened species criteria">Wildlife and ecosystems section. [http://www.ehp.qld.gov.au/wildlife/threatened-species/ Threatened species criteria]. [[Department of Environment and Heritage Protection (Queensland)]]. Retrieved November 8, 2013.</ref> |
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* [[South Australia]]: ([[Outback]] regional status) ''Least Concern''.<ref name= "SAAL Regional Species Conservation Assessment">(Last updated: 19/07/2013). [http://www.environment.sa.gov.au/files/fa467d92-1a9f-416d-a215-a1ff00fe3697/saal-regional-conservation-assessments-rep.pdf SAAL Regional Species Conservation Assessment Project] (PDF sheet download, pages 50, 67) . [[Department of Environment, Water and Natural Resources (South Australia)]]. Retrieved November 8, 2013.</ref> |
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* [[Queensland]]: ''Near Threatened'' <ref>[http://www.ehp.qld.gov.au/wildlife/threatened-species/near-threatened/near_threatened_animals.html#reptiles_49_species Near threatened animals / Reptiles list]. [[Department of Environment and Heritage Protection (Queensland)]]. Retrieved November 8, 2013.</ref> (used to be officially ''Rare'' <ref name="Inland taipan conservation">Australian Reptile Online Database. [http://www.arod.com.au/arod/reptilia/Squamata/Elapidae/Oxyuranus/microlepidotus?tab=conservation Inland taipan conservation]. arod.com.au. Retrieved November 8, 2013.</ref><ref name= ""Rare" category">Threatened species (22 November 2012) . [http://www.ehp.qld.gov.au/wildlife/threatened-species/rare/index.html "Rare" category]. [[Department of Environment and Heritage Protection (Queensland)]]. Retrieved November 8, 2013.</ref>). The [[Australian Museum]] and the [[Taronga Conservation Society]] quote it as ''Rare''.<ref name="ANIMAL SPECIES:Inland Taipan"/><ref>(September 28, 2012)[http://taronga.org.au/blog/2012-09-28/meet-worlds-deadliest-snake-safety Meet the world's deadliest snake in safety]. [[Taronga Conservation Society]]. Retrieved November 8, 2013.</ref> |
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* [[New South Wales]]: ''Extinct''.<ref name="Fierce Snake - profile"/> The [[Australian Museum]] quotes it as ''Presumed Extinct''.<ref name="ANIMAL SPECIES:Inland Taipan"/> |
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* [[Victoria (Australia)|Victoria]]: ''Regionally Extinct''.<ref name= "Threatened Vertebrate Fauna in Victoria">Conservation status (March 2013) . [http://www.dse.vic.gov.au/__data/assets/pdf_file/0008/158642/Advisory-List-of-Threatened-Vertebrate-Fauna_FINAL-2013.pdf Advisory List of Threatened Vertebrate Fauna in Victoria]. (Small-scaled Snake, page 14) [[Department of Sustainability and Environment]]. Retrieved November 11, 2013.</ref> The [[Australian Museum]] quotes it as ''Presumed Extinct'' <ref name="ANIMAL SPECIES:Inland Taipan"/> |
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=== In captivity === |
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According to the [[International Species Information System]] (retrieved 2004), inland taipans are held in three [[zoo]] collections: [[Adelaide Zoo]], Sydney [[Taronga Zoo]] in Australia and [[Moscow Zoo]] in [[Russia]].<ref name= "Births and Hatchings / Moscow">AEZA news (January–March, 2004) . [http://www.eaza.net/News/EAZA_Magazine/EAZA%20NEWS%20Magazine/EN45.pdf Births and Hatchings / Moscow - Russian federation]. (page 17) [[European Association of Zoos and Aquaria]] Magazine. Retrieved November 11, 2013.</ref> In the Moscow Zoo they are kept in the "House of Reptiles" which is not usually open for the general public.<ref name= "Amazing World of Amphibians and Reptiles">(May 1, 2007) . [http://www.moscowzoo.ru/get.asp?Id=N47 Amazing World of Amphibians and Reptiles exhibition opens] . [[Moscow Zoo]] Retrieved November 11, 2013.</ref><ref name= "MOSCOW, unique Zoo">UK Independent Zoo Enthusiasts Society, "Zoo Grapevine" newsletter (Fall, 2012) . [http://translate.google.com/translate?hl=en&sl=&tl=en&u=http%3A%2F%2Fwww.moscowzoo.ru%2Fget.asp%3FID%3DC262 MOSCOW, Unique Zoo - Article from the "Zoo Grapevine" / "BEHIND THE SCENES"]. (English translation via Google) [[Moscow Zoo]]. Retrieved November 11, 2013.</ref> |
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The inland taipan is also on public display in Australia at the [[Australia Zoo]],<ref name="REPTILES - FIERCE SNAKE"/> [[Australian Reptile Park]],<ref name="Australian Reptile Park Inland Taipan ">Our Animals . [http://www.reptilepark.com.au/animals.asp?catID=16&ID=112 Fierce Snake (Inland Taipan)]. [[Australian Reptile Park]]. Retrieved November 11, 2013.</ref> [[Billabong Sanctuary]]<ref name="billabongsanctuary.com.au" /> and the [[Cairns Tropical Zoo]].<ref>[http://www.cairnstropicalzoo.com.au/wildlife_displays.html Wildlife displays / The Reptile House] . Retrieved November 11, 2013</ref> |
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Outside of Australia: [[Kentucky Reptile Zoo]] ([[USA]]),<ref name=" Adopt a Zoo Animal">Help support KRZ. [http://www.kyreptilezoo.org/?Help_Support_KRZ:Adopt_a_Zoo_Animal Adopt a Zoo Animal / AUSTRALIAN INLAND TAIPAN]. [[Kentucky Reptile Zoo]]. Retrieved November 11, 2013.</ref> [[Animal World & Snake Farm Zoo]] ([[Texas]], USA),<ref name="Fox San Antonio 1">News (October 10, 2013).[http://www.youtube.com/watch?v=FdxHnZ50XUk Street's Corner: Houdini Heir Tries To Escape World's Deadliest Snake]. [[KABB]] . (KABB "Fox San Antonio" official YouTube Channel). Retrieved November 11, 2013.</ref><ref name="Seguin Gazette 1">Maloney, Ron (October 9, 2013). [http://seguingazette.com/news/article_c442da88-3067-11e3-bf96-001a4bcf887a.html Houdini descendant to perform in Seguin]. [[Seguin Gazette]]. Retrieved November 11, 2013.</ref><ref name="Patoski, Joe Nick">Patoski, Joe Nick (July 14, 2011). [http://www.nytimes.com/2011/07/15/us/15ttpatoski.html Snake Farm’s Charms Still Casting Spells]. [[The New York Times]]. Retrieved November 11, 2013.</ref> |
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==== Private ownership law ==== |
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In Australia, owning an inland taipan requires a Class 2, Category 3 [R5] License (the highest). A person who wishes to keep reptiles, he or she must get a license from the appropriate state authority – such as the [[Office of Environment and Heritage (New South Wales)|Office of Environment and Heritage]] in [[New South Wales]]. The reptile licensing and record-keeping system allows the authorities to monitor which reptile species are being kept, bred and traded amongst enthusiasts. The Class 2 license is only available to people who are over the age of 18 years who have had at least two years experience in caring for Class 1 reptiles. Additional criteria need to be met before venomous species may be kept. The venomous snakes in the Class 2 license are grouped into three sub-categories and the most dangerous species can be kept only by the more experienced keepers.<ref name="licence to keep reptiles">Wildlife licenses (September 24, 2013) . [http://www.environment.nsw.gov.au/wildlifelicences/GettingAReptileKeepersLicence.htm Getting an animal keeper's licence to keep reptiles] (Class 2 licence) . [[Office of Environment and Heritage (New South Wales)]]. Retrieved November 13, 2013.</ref> |
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==Appearance== |
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[[Image:Fierce Snake.jpg|thumb|200px|left|Brown-coloured (winter)]] |
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[[Image:FierceSnakeOlive.jpg|thumb|200px|left|Olive-coloured (summer)]] |
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The inland taipan is dark tan, ranging from a rich, dark hue to a brownish light-green, depending on season. It has 23 rows of [[dorsal scales]] at midbody, between 55 and 70 divided [[subcaudal scales]], and one [[anal scale]]. Its back, sides and tail may be different shades of brown and grey, with many scales having a wide blackish edge. These dark-marked scales occur in diagonal rows so that the marks align to form broken chevrons of variable length that are inclined backward and downward. The lowermost lateral scales often have an anterior yellow edge. The dorsal scales are smooth and without keels. The round-snouted head and neck are usually noticeably darker than the body (glossy black in winter, dark brown in summer), the darker colour allowing the snake to heat itself while only exposing a smaller portion of the body at the burrow entrance. The eye is of average size with a blackish brown iris and without a noticeable coloured rim around the pupil. The head of the inland taipan is not distinct from the neck, as it is on [[Coastal Taipan]]s, the body is streamlined.<ref name="billabongsanctuary.com.au"/> |
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The inland taipan averages approximately {{convert|1.8|m|ft}} in total length, although larger specimens can reach total lengths of {{convert|2.5|m|ft}}.<ref name="Australian Reptile Park Inland Taipan "/> Its [[fangs]] length are between 3.5 to 6.2 mm long (shorter than the fangs of the Coastal taipan).<ref name="billabongsanctuary.com.au"/> |
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===Seasonal adaptation=== |
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Dramatic seasonal colour changes take place, with a darker winter and lighter summer coloration. These changes are an adaptation to the harsh [[outback]] climate, the darker markings absorbing heat more efficiently in winter and the reverse in summer.<ref name="Fierce Snake - profile"/> The head especially may take on an almost glossy black appearance at times in [[Wildlife|wild]] specimens, and lighter in [[Captivity (animal)|captive]] specimens.<ref name="Fierce Snake - profile"/><ref name= "Welton, Ronelle Ellen"/> |
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==Behavior== |
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The species is primarily, if not exclusively, [[Diurnality|diurnal]] in its activity on the surface although it may become [[nocturnal]] in hot weather conditions. They are most active in the early half of the morning, briefly [[Ectotherm|basking]] and [[foraging]] in or near deep soil cracks and animal [[burrow]]s, before retiring to shelter for the rest of the day. In cooler weather the snakes may also be found active in the afternoon.<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="saalnrm.sa.gov.au"/> |
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===Diet=== |
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Unlike [[Snake#Feeding and diet|most snakes]], the inland taipan is a specialist [[mammal]] [[Predation|hunter]]; so its venom is specially adapted to kill [[warm-blooded|warm-blooded species]].<ref name="abc.net.au"/><ref name="venomsupplies.com"/> |
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In the wild, the inland taipan appears to feed entirely on small to medium-sized mammals, particularly the [[Long-haired Rat|long-haired rat]] (''Rattus villosissimus'') which at times reaches plague proportions in this region, as well as the [[Plains Rat|plains rat]] (''Pseudomys australis''), the introduced [[House Mouse|house mouse]] (''Mus musculus''), and various small [[Dasyurid]]s.<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="REPTILES - FIERCE SNAKE"/><ref name="Fierce Snake - profile"/> Taipans detect their prey by sensing movement and odour. They seem to have better eyesight than many other snakes. They flick their forked tongue rapidly in and out of the mouth, "tasting" the presence on the air of potential [[Predation|prey]] animals. This chemical information is passed to the [[Vomeronasal organ|Jacobson’s organ]] in the roof of the mouth, and then to the brain.<ref name="billabongsanctuary.com.au"/> Prey is usually cornered in a [[burrow]] or soil crack. The taipan, unable to retreat from its prey in this confined space, has a greater need to finish it off quickly.<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="billabongsanctuary.com.au"/> Unlike other venomous snakes that strike with a single, accurate bite then retreat while waiting for the prey to die, the fierce snake subdues the prey with a series of rapid, accurate strikes. It is known to deliver up to eight venomous bites in a single attack.<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="Fierce Snake - profile"/> Its more risky attack strategy entails holding its prey with its body and biting it repeatedly.<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="Newsletter No.80"/><ref name="toxinology.com"/><ref name="billabongsanctuary.com.au"/> This injects the extremely toxic venom deep into the prey. The venom acts so rapidly that its prey does not have time to fight back.<ref name="billabongsanctuary.com.au"/> |
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Populations of this snake are highly dependent on the availability of its favourite prey, the long-haired rat. This rat species goes through “boom-and-bust” cycles, breeding up to plague proportions during the good seasons and virtually disappearing during times of drought. When rats are in high numbers, the snakes grow very sleek and fat. However, once the rats disappear, the snakes must depend on less prevalent prey and/or draw upon their fat reserves until the rats return.<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="REPTILES - FIERCE SNAKE"/> |
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In captivity fierce snakes may also accept day-old [[Bird|chicks]] in addition to rats and mice.<ref name="ANIMAL SPECIES:Inland Taipan"/> |
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===Mating and reproduction=== |
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Because they live in such a remote, inhospitable part of the Australia, and are shy and retreating by nature, most information on [[Breeding in the wild|breeding behaviour]] of inland taipans comes from observation of [[Captivity (animal)|captive]] snakes.<ref name="billabongsanctuary.com.au"/> |
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[[Mating]] occurs in spring, anytime from August through December. Like coastal taipans, male inland taipans may engage in a spectacular competitive display called [[Sexual selection in snakes|ritualistic combat]]. In this test of strength, they wrap around each other’s bodies like a coiled rope, wrestling with each other till the stronger snake forces his rival’s head to the ground. The struggle may last for hours, until the stronger male finally wins the right to mate with the female. If the female is receptive, he rubs his chin up and down her body, then twists the lower part of his body under hers. Males have two sex organs, called [[hemipenes]], but only one at a time is used for mating. Mating may last for several hours, and a female may mate with more than one male during the [[Seasonal breeder|breeding season]].<ref name="billabongsanctuary.com.au"/> Females with [[Fallopian tube|oviducal]] eggs can be found in mid-spring (second half of November).<ref name="ANIMAL SPECIES:Inland Taipan"/> About 2 months after mating, the female lays up to 20 eggs, with an average [[Clutch (eggs)|clutch]] size of 16 eggs. Older females (which have a larger body size) generally lay more eggs than younger ones. Taipan eggs are elongated in shape, with a [[wikt:leathery|leathery]], [[wikt:permeable|permeable]] shell. Females will not usually mate every year because of the high energy costs and risks associated with reproduction.<ref name="billabongsanctuary.com.au"/> Reproduction rate is also influenced by the availability of food. If food is scarce, the snake will reproduce less.<ref name="Fierce Snake - profile"/> |
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In captivity, females can produce two clutches within what would effectively be one [[breeding season]].<ref name="ANIMAL SPECIES:Inland Taipan"/> |
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After depositing her eggs, the female abandons the nest site. Hatching occurs about 2 months later.<ref name="billabongsanctuary.com.au"/> The eggs measure 6 x 3.5 cm when laid and take 9–11 weeks to hatch at 27–30[[Celsius|°C]].<ref name="ANIMAL SPECIES:Inland Taipan"/> The eggs are usually laid in abandoned animal [[burrows]] and deep [[Fracture (geology)|crevices]].<ref name="Fierce Snake - profile"/> Young snakes grow very fast under favourable conditions. Males and females grow to about the same size. Male Taipans reach sexual maturity at about 16 months, and females at about 28 month of age.<ref name="billabongsanctuary.com.au"/> |
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[[Captivity (animal)|Captive]] snakes generally live for 10 to 15 years. An inland taipan at [[Australia Zoo]] lived to be over 20 years old.<ref name="billabongsanctuary.com.au"/> |
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===Natural threats=== |
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The king brown snake (''[[Pseudechis australis]]'') is immune to most [[Snakes of Australia|Australian snake]] [[venom]], and is known to also eat young inland taipans.<ref name= "Animal Weapons: Episode 1">[http://www.youtube.com/watch?v=OzIzeFPCFWI&feature=youtu.be&t=5m25s Animal Weapons: Episode 1 – Chemical Warfare / Inland Taipan (5m25s)]. Absolutely Wild Visuals Youtube channel, ([http://www.focalint.org/footage-and-content-gallery/directory/member/1104/absolutely-wild-visuals AWV stock footage library] / [[FOCAL International]]) Retrieved October 18, 2013.</ref> The [[perentie]] (''Varanus giganteus''), is a large [[monitor lizard]] which also shares the same [[habitat]]. As it grows large enough, it will readily tackle large venomous snakes for [[prey]].<ref>Our Animals/Reptiles/Monitors. [http://www.reptilepark.com.au/animalprofile.asp?id=90 Perentie – Varanus giganteus]. [[Australian Reptile Park]]. Retrieved October 19, 2013.</ref> |
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===Interaction with humans=== |
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Many reptile [[Zookeeper|keepers]] regard it as a [[Peace|placid]] snake to handle.<ref name="ANIMAL SPECIES:Inland Taipan"/> |
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Inland taipans are rarely encountered in the wild by the average person because of their remoteness and brief above-ground appearance during the day. Although highly venomous, compared with the related [[coastal taipan]] (and despite the alternative name ‘Fierce Snake’), this species is actually quite shy and [[reclusive]], with a [[wikt:placid|placid]] [[disposition]],<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="saalnrm.sa.gov.au"/><ref name="toxinology.com"/><ref name="Judith {Judy} Martin"/> and prefers to escape from trouble.<ref name="newsfeed.time.com" /><ref name="Fierce Snake - profile"/> So long as a person is not creating much vibration and noise the inland taipan may not feel alarmed or bothered by a human presence.<ref name="saalnrm.sa.gov.au"/><ref name="toxinology.com"/><ref>The Ten Deadliest Snakes in the World with [[Steve Irwin]], ITV (1998) film clip. [http://www.wildfilmhistory.org/film/310/clip/447/Lick+of+death.html "Lick of death"]. wildfilmhistory.org. Retrieved October 15, 2013.</ref><ref>[[Steve Backshall]] talks about his rare encounter with an inland taipan (May 19, 2013) film clip. [http://www.youtube.com/watch?v=py4USk-Nd1g "*YouTube Exclusive* Steve Backshall on world's deadliest snake - Deadly 60 in Australia"]. [[BBC Earth]] (official YouTube channel). Retrieved October 28, 2013.</ref> |
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However, caution should be exercised and a safe distance maintained as it can inflict a potentially fatal bite.<ref name="saalnrm.sa.gov.au"/> Like any animal, the inland taipan will defend itself when provoked,<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="Fox San Antonio 1"/><ref name= "Steve Backshall 2"/> mishandled<ref name="Judith {Judy} Martin" /> or prevented to escape.<ref name="newsfeed.time.com"/> Firstly it makes a threat display by raising its forebody in a tight low S-shaped curve with its head facing the offender. Should the offender choose to ignore the warning the inland taipan will strike.<ref name="ANIMAL SPECIES:Inland Taipan"/><ref name="newsfeed.time.com"/><ref name="toxinology.com"/> It is an extremely fast and [[Agility|agile]] snake which can [[Strike (attack)|strike]] instantly with extreme accuracy,<ref name="newsfeed.time.com"/><ref name="ReferenceA"/> making a single bite or several quick bites,<ref name="ANIMAL SPECIES:Inland Taipan"/> often snapping its jaws fiercely several times to inflict multiple [[Penetrating trauma|punctures]] in the same attack,<ref name="ReferenceA">Clinical Toxinology Resources. [http://toxicology.ucsd.edu/Snakebite%20Protocols/Oxyura~1.htm Snakebite Protocols – ''Oxyuranus microlepidotus'']. "'''Signs and Symptoms of Envenomation:''' ''E. Fang Marks:'' The snake strikes with extraordinary speed and accuracy, often snapping its jaws fiercely several times which can result in multiple punctures in the same attack."; "'''Special Considerations:''' ''A. Multiple Bites:'' The Inland Taipan is an extremely fast and agile snake which can strike instantly with extreme accuracy. It is possible for a Taipan to deliver more than one bite in a single attack." [[University of Adelaide]]. Retrieved October 18, 2013.</ref> and it [[Envenomation|envenoms]] in almost every case.<ref name=" Dr Geoff Isbister">ABC News 24 (September 27, 2012) . [http://www.abc.net.au/news/2012-09-27/hunter-teen-bitten-by-deadly-snake/4282944 Teen hospitalised after bite from deadly Taipan]. (Quoting Toxicologist, [https://research.calvarymater.org.au/meet-our-researchers/geoff-isbister.html Dr Geoff Isbister]) . [[Australian Broadcasting Corporation]]. Retrieved November 13, 2013.</ref> |
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==Venom== |
==Venom== |
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The inland taipan's [[venom]] consists of [[Taipoxin]] and [[protease]] enzymes. The average quantity of venom delivered by this species is 44 mg and the maximum dose recorded is 110 mg. The [[median lethal dose]] (LD<sub>50</sub>) for mice is 2 μg/kg (ppb) for pure Taipoxin<ref name=EurJBiochem>{{cite journal|doi=10.1111/j.1432-1033.1976.tb10833.x|author=Fohlman, J.; Eaker, D.; Karlsoon, E. and Thesleff, S. |title=Taipoxin, an extremely potent presynaptic neurotoxin from the venom of the australian snake taipan ''(Oxyuranus s. scutellatus)''. Isolation, characterization, quaternary structure and pharmacological properties|journal=Eur. J. Biochem. |year=1976|pages=457–69|pmid=976268|volume=68|issue=2}}</ref> and 30 μg/kg (ppb) for the natural venom mixture.<ref name="UoB_Strength">{{cite web|title=Strength of Venom|url=http://www.chm.bris.ac.uk/webprojects2003/stoneley/strength.htm|work=School of Chemistry, University of Bristol|accessdate=2008-02-29}}</ref> Its venom consists mostly of [[neurotoxin]]s. Almost all positively identified inland taipan bite victims have been [[herpetologist]]s handling the snakes for study, and all were treated successfully with [[antivenom]]—no recorded incidents have been fatal since the advent of the specific antivenom therapy.<ref name="Barrett2003">{{cite journal |doi=10.1046/j.1442-2026.2003.00509.x |last=Barrett |first=Robyn |coauthors=Mark Little |year=2003 |month=Oct–Dec |title=Five years of snake envenoming in far north Queensland |journal=Emergency Medicine |volume=15 |issue=5–6 |pages=500–510 |url= |quote= |pmid=14992068 }}</ref><ref name="INCHEM">{{cite web |last=White |first=Julian |title=''Oxyuranus microlepidotus'' |url=http://www.inchem.org/documents/pims/animal/taipan.htm |date=November 1991 |publisher=Chemical Safety Information from Intergovernmental Organizations |accessdate=24 July 2009}}</ref> |
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The inland taipan's [[Snake venom|venom]], drop for drop, is by far the most [[Toxicity|toxic]] of any snake in the world – much more so than even [[Sea Snake|sea snakes]].<ref name="ANIMAL SPECIES:Inland Taipan" /><ref name="avru.org" /><ref name="viper.arizona.edu" /><ref name= "Department of Wildlife Ecology and Conservation">Department of Wildlife Ecology and Conservation. [http://ufwildlife.ifas.ufl.edu/venomous_snake_faqs.shtml Frequently Asked Questions About Venomous Snakes]. "A comparative study found that the snake venom that is most toxic to mice (of the species tested) is that of the Inland Taipan (''Oxyuranus microlepidotus''), found in Australia." [[University of Florida]]. Retrieved November 5, 2013.</ref><ref name="Hodgson et al 2007" /><ref name="Bell KL 1998" /><ref name="9 of the World's Deadliest Snakes" /><ref name="Inland Taipan page" /><ref name="[[Steve Irwin]] presentation" /><ref name="science.org.au" /><ref name="Journal of Herpetology Vol.17" /><ref name="Dr. Bryan Grieg Fry - Interview" /> Unlike [[Snake#Feeding and diet|most snakes]], the inland taipan is a specialist [[mammal]] [[Predation|hunter]] so its venom is specially adapted to kill [[warm-blooded|warm-blooded species]].<ref name="abc.net.au" /><ref name="venomsupplies.com" /> It is estimated that one bite possesses enough [[lethality]] to kill at least 100 full grown men,<ref name="Journal of Herpetology Vol.17" /><ref name="REPTILES - FIERCE SNAKE" /><ref name="Newsletter No.80" /><ref name="newsfeed.time.com"/> and, depending on the nature of the bite (place of bite, amount of venom, victim's health and sensitivity etc.), can kill someone in as little as 30 to 45 minutes if left untreated.<ref name= "INCHEM"/><ref name="toxicology.ucsd.edu"/><ref name="smh.com.au"/><ref name="australiantimes.co.uk"/> |
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==Gallery== |
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The average quantity of venom delivered by this species is 44 mg and the maximum dose recorded is 110 mg, compared to the [[Indian cobra]] (''Naja naja'')169 mg/max 610 mg, and the [[North America]]n eastern diamondback rattlesnake (''[[Crotalus adamanteus]]'') 410 mg/max 848 mg [[Et cetera|etc.]]<ref name="avru.org"/> |
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<gallery widths=240px heights=130px> |
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Image:Fierce Snake.jpg|Brown-coloured (winter) |
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The [[median lethal dose]] (LD<sub>50</sub>), [[Subcutaneous injection|subcutaneous]] (the most applicable to actual bites) for mice is 0.025 mg/kg<ref name="INCHEM"/><ref name="avru.org"/> (0.01 mg/kg subcutaneous, in [[bovine serum albumin]]).<ref name="INCHEM"/><ref name="Hodgson et al 2007"/> Compared to the [[beaked sea snake]] (''Enhydrina schistosa'') 0.164 mg/kg, Indian cobra 0.565 mg/kg, North American eastern diamondback rattlesnake 11.4 mg/kg, etc.,<ref name="avru.org"/> the inland taipan has a smaller venom yield than its cousin the [[coastal taipan]] yet its venom is almost four times as toxic.<ref name="Newsletter No.80"/><ref name="World's Deadliest Snakes" /> |
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Image:FierceSnakeOlive.jpg|Olive-coloured (summer) |
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</gallery> |
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[[Intravenous therapy|Intravenous]], [[Intraperitoneal injection|intraperitoneal]] and [[Intramuscular injection|intramuscular]] LD<sub>50</sub> for the inland taipan venom have not been tested.<ref name="Fry, Bryan, Deputy Director, Australian Venom Research Unit, University of Melbourne">Fry, Bryan, Deputy Director, Australian Venom Research Unit, University of Melbourne (March 9, 2002). [http://web.archive.org/web/20120413182323/http://www.venomdoc.com/LD50/LD50men.html "Snakes Venom LD<sub>50</sub> – list of the available data and sorted by route of injection "]. venomdoc.com. (archived) Retrieved October 14, 2013.</ref> |
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[[Belcher's sea snake]] (''Hydrophis belcheri'') is sometimes erroneously popularized as the most venomous snake in the world.<ref name="Dr. Bryan Grieg Fry - Interview"/> Its actual LD<sub>50</sub> (recorded only intramuscularly) is 0.24 mg/kg<ref>{{cite journal |pmid=4818649 |year=1974 |last1=Tamiya |first1=N |last2=Puffer |first2=H |title=Lethality of sea snake venoms |volume=12 |issue=1 |pages=85–7 |journal=Toxicon |doi=10.1016/0041-0101(74)90104-4}}</ref> and 0.155 mg/kg,<ref name="Fry, Bryan, Deputy Director, Australian Venom Research Unit, University of Melbourne"/> less lethal than other sea snakes such as the [[olive sea snake]] (''Aipysurus laevis'') 0.09 mg/kg and the most toxic intramuscularly, recorded of the sea snakes - the [[Hydrophis|black-banded robust sea snake]] (''Hydrophis melanosoma'') 0.082 mg/kg. The black-banded robust sea snake has also been tested subcutaneously registering at 0.111 mg/kg. more than four times less toxic than the inland taipan's venom. In the LD<sub>50</sub> subcutaneous test it is actually [[Dubois' sea snake]] (''Aipysurus duboisii'') which has the most toxic venom of the any of the sea snakes tested, registering at 0.044 mg/kg. Still nearly half less lethal as the inland taipan's venom.<ref name="Fry, Bryan, Deputy Director, Australian Venom Research Unit, University of Melbourne"/> |
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The biological properties and toxicity of a baby inland taipan's venom are not significantly different or weaker than that of an adult inland taipan's.<ref name= "Animal Weapons: Episode 1"/><ref>{{cite journal |pmid=8470140 |year=1993 |last1=Tan |first1=NH |last2=Ponnudurai |first2=G |last3=Mirtschin |first3=PJ |title=A comparative study of the biological properties of venoms from juvenile and adult inland taipan (''Oxyuranus microlepidotus'') snake venoms |volume=31 |issue=3 |pages=363–7 |journal=Toxicon |doi=10.1016/0041-0101(93)90155-C}}</ref> |
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The inland taipan's venom consists of:<ref name="toxinology.com"/> |
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* [[Neurotoxin]]s: [[Presynaptic]] neurotoxins; Paradoxin,<ref name="Hodgson et al 2007"/> and [[Postsynaptic]] neurotoxins;<ref name="INCHEM"/> Oxylepitoxin-1,<ref>{{cite journal |doi=10.1016/j.peptides.2006.06.003 |title=Oxylepitoxin-1, a reversible neurotoxin from the venom of the inland taipan (''Oxyuranus microlepidotus'') |year=2006 |last1=Clarke |first1=Carol |last2=Kuruppu |first2=Sanjaya |last3=Reeve |first3=Shane |last4=Ian Smith |first4=A. |last5=Hodgson |first5=Wayne C. |journal=Peptides |volume=27 |issue=11 |pages=2655–60 |pmid=16879898}}</ref> alpha-oxytoxin 1, alpha-scutoxin 1<ref>{{cite journal |doi=10.1016/j.neuro.2009.12.009 |title=Variations in the pharmacological profile of post-synaptic neurotoxins isolated from the venoms of the Papuan (''Oxyuranus scutellatus canni'') and coastal (''Oxyuranus scutellatus scutellatus'') taipans |year=2010 |last1=Kornhauser |first1=Rachelle |last2=Hart |first2=Andrew J. |last3=Reeve |first3=Shane |last4=Smith |first4=A. Ian |last5=Fry |first5=Bryan G. |last6=Hodgson |first6=Wayne C. |journal=NeuroToxicology |volume=31 |issue=2 |pages=239–43 |pmid=20036687}}</ref> – affecting the [[nervous system]]. |
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* [[Hemotoxin]]s ([[procoagulant]]s) – affecting the [[blood]]. |
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* [[Myotoxin]]s – affecting the [[muscles]]. |
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* possibly [[Nephrotoxin]]s – affecting the [[kidneys]]. |
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* possibly Haemorrhagins<ref>Clinical Toxinology Resources. [http://www.toxinology.com/fusebox.cfm?staticaction=snakes/ns-venmed43.htm Haemorrhagins]. [[University of Adelaide]]. Retrieved October 18, 2013.</ref> – affecting the blood vessels ([[Endothelium]]). |
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To date (2005), the majority of components in the venom of the taipan have not been characterized and little [[Molecule|molecular]] research has been undertaken on taipan (''Oxyuranus'') species at large. The [[amino acid]] sequences of only seven [[proteins]] from inland taipan have been submitted to [[UniProt|SWISS-PROT]] databases. This number represents a small proportion of possibly hundreds of proteins within its venom not yet described. Due to the number of [[peptides]] as yet undiscovered, there is much exploratory work that needs to be conducted.<ref name= "Welton, Ronelle Ellen"/> |
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===Clinical effects=== |
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The [[mortality rate]] is high in untreated cases<ref name="australianprescriber.com">Geoffrey K Isbister (2006). [http://www.australianprescriber.com/magazine/29/5/125/9/ "Snake bite: a current approach to management"]. [[NPS MedicineWise#Publications|Australian Prescriber]]. Retrieved October 14, 2013.</ref> |
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* Dangerousness of bite: Severe [[Envenomation|Envenoming]] likely, high [[lethality]] potential. |
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* Rate of Envenoming: >80% . |
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* Untreated Lethality Rate: >80% .<ref name="toxinology.com"/> |
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Clinically, envenomation may represent a complex scenario of multiple organ system poisoning with [[neurotoxic]] symptoms typically dominating. [[Acute kidney injury|Acute renal failure]], [[rhabdomyolysis]], and [[Disseminated intravascular coagulation|disseminated coagulopathy]] may also complicate the setting.<ref name="ReferenceA"/> |
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The first local and general symptoms of a bite are local pain and variable non-specific effects which may include headache, nausea, vomiting, [[abdominal pain]], diarrhoea, dizziness, collapse or [[convulsions]] leading to major organ effects: [[neurotoxicity]], [[coagulopathy]], [[rhabdomyolysis]] or [[renal failure]]/damage and finally [[death]]<ref name="toxinology.com"/><ref name="australianprescriber.com"/> |
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The snake's venom is a neurotoxin that contains a "spreading factor" ([[hyaluronidase]] enzyme) that increases the rate of absorption and thus acts quickly.<ref name="ANIMAL SPECIES:Inland Taipan"/> Inland taipan snake venom contains potent presynaptic neurotoxins (toxins in venom that cause [[paralysis]] or muscle weakness). Also present are postsynaptic neurotoxins, which are less potent but more rapid acting than the presynaptic neurotoxins.<ref name="Clinical Toxinology Resources 2013">Clinical Toxinology Resources. [http://www.toxinology.com/about/taipan_snake_snakebite.html Australian Taipan Snakes – Venom of Taipan snakes]. [[University of Adelaide]]. Retrieved October 16, 2013.</ref> Presynaptic neurotoxins disrupt [[neurotransmitter]] release from the [[axon terminal]]. This takes days to resolve and does not respond to [[antivenom]]. Postsynaptic neurotoxins competitively block [[acetylcholine receptor]]s but the effect can be reversed by antivenom. [[Neurotoxic]] [[Envenomation|envenoming]] causes a progressive descending [[flaccid paralysis]]: [[Ptosis (eyelid)|ptosis]] is usually the first sign, then facial ([[dysarthria]]) and [[bulbar]] involvement progressing to [[dyspnea]] and [[respiratory paralysis]] leading to [[suffocation]] and [[Weakness#Peripheral muscle fatigue|peripheral weakness]].<ref name= "Welton, Ronelle Ellen"/><ref name="australianprescriber.com"/> Because it can act so fast, it can kill a person within about 45 minutes. There have been reports of people experiencing effects of venom within half an hour as well.<ref name="smh.com.au"/><ref name="theaustralian.com.au">AFP (September 27, 2012). [http://www.theaustralian.com.au/news/nation/teenager-bitten-by-inland-taipan-in-hunter-valley/story-e6frg6nf-1226482315063 "Teenager bitten by inland taipan in Hunter Valley"]. [[The Australian]]. Retrieved October 14, 2013.</ref> The development of general and/or respiratory paralysis is of paramount concern in that these are often difficult to reverse once established, even with large amounts of antivenom. Prolonged [[intubation]] and [[Mechanical ventilation|ventilatory support]] (perhaps up to 1 week or longer) may be required. Early diagnosis of neurotoxic symptoms with prompt and adequate dosages of antivenom is critical to avoid these complications.<ref name="ReferenceA"/> |
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Comparative [[Electrophoresis|electrophoretic]] studies have been conducted with the venoms from the coastal taipan and the inland taipan, and indicated significant differences exist between the components of these venoms (Broad et al., 1979a). Further studies have shown that inland taipan venom has a higher [[hyaluronidase]] activity compared to coastal taipan venom. [[In vitro]], inland taipan possesses post-synaptic neuromuscular activity blocking smooth [[muscle contraction]] and [[Vasodilation|vasorelaxation]] activities, and [[in vivo]], produces transient respiratory and cardiovascular collapse (Bell et al., 1998 and 1999). Although [[CSL Limited|CSL]] [[antivenom]] [[Neutralizing antibody|neutralised]] the effects of their respective presynaptic neurotoxic (paradoxin and taipoxin) and the post-synaptic activity of coastal taipan venom, the post-synaptic activity of inland taipan venom was not neutralised.<ref name= "Welton, Ronelle Ellen"/> |
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The venom also contains a potent hemotoxin ([[procoagulant]]s) a [[Thrombin|prothrombin]] activator that leads to consumption of major [[coagulation]] factors including [[fibrinogen]], toxins in venom that interfere with [[blood clotting]]. This causes [[Disseminated intravascular coagulation|defibrination]], with non-clottable blood, putting victims at risk of major bleeding from the bite site and can lead to more serious, sometimes fatal, internal [[haemorrhaging]], especially in the brain. Recovering from this takes many hours after venom neutralisation has been achieved with antivenom.<ref name="australianprescriber.com"/> Taipan snake procoagulants are amongst the most powerful snake venom procoagulants known.<ref name="Clinical Toxinology Resources 2013"/> Though mild coagulopathy has been reported for inland taipan envenomation (Sutherland and Tibballs, 2001).<ref name= "Welton, Ronelle Ellen"/> |
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No nephrotoxins (kidney toxins) have so far been isolated from inland taipan snake venoms, but renal (kidney) impairment or acute [[renal failure]] can occur secondary to severe [[rhabdomyolysis]].<ref name="australianprescriber.com"/> Taipan snake venom does contain myotoxins that cause myolysis ([[rhabdomyolysis]], muscle damage);<ref name="Clinical Toxinology Resources 2013"/> The urine of a bite victim often turns reddish-brown as their muscles dissolve and are passed through the kidneys ([[Myoglobinuria]]). The kidneys are often badly damaged by filtering so much tissue debris out of the blood, and kidney failure is a common complication in serious cases where there is significant [[envenomation|envenoming]].<ref name="abc.net.au"/> |
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Causes of death:<ref name="INCHEM"/> |
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* [[Paralysis]] = primary, e.g., [[respiratory failure]]; secondary, e.g., [[pneumonia]] |
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* [[Coagulopathy]] = primary, [[Exempli gratia#exempli gratia|e.g.]], [[cerebral haemorrhage]]; secondary, e.g., [[renal failure]]. |
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* [[Renal failure]] = includes secondary complications such as [[infections]]. |
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* [[Anaphylaxis]] = acute [[allergic reaction]] to venom in a patient previously exposed to taipan snake venom (e.g., reptile keeper). |
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* [[Cardiac arrest|Cardiac complications]] likely to be secondary. |
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===Antivenom=== |
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Until 1955, the only [[antivenom]] available for general distribution for [[Snakes of Australia|Australian snakes]] was the monovalent (specific) [[tiger snake]] (''Notechis'') antivenom, which gave varying degrees of cross-protection against the bites of most other dangerous Australian snakes. Thereafter followed specific anti-venom for other common snakes among them the [[coastal taipan]], and finally, a polyvalent (broad spectrum) antivenom, a combined antivenom for the bites of any unidentified snake from Australia. |
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The coastal taipan anti-venom, known as "taipan antivenom",<ref name="venomsupplies.com"/> is effective against the inland taipan venom as well. But it has also been shown that it may not be as effective in bite victims of inland taipan as in the case of coastal taipan bite victims (Lalloo et al., |
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1995a; Trevett et a!., 1995; Southern et al., 1996; Crachi et al., 1999a; Currie, 2000).<ref name= "Welton, Ronelle Ellen"/> |
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Taipan [[antivenom]] is produced and manufactured by the [[Australian Reptile Park]] and the [[CSL Limited|Commonwealth Serum Laboratories]] in [[Melbourne]].<ref>Anti-Venom Program. [http://www.reptilepark.com.au/about-us/history/park-founder-eric-worrel/antivenom-program/ Involvement with the Anti-Venom Program]. [[Reptile Gardens]]. Retrieved October 18, 2013.</ref> |
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===Snakebite victims=== |
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In September 2012, in the small city of [[Kurri Kurri, New South Wales]], north of [[Sydney]], more than 1000 kilometres away from the snake's natural environment, a teenage boy was bitten on the finger by an inland taipan. The teenager's rapid self application of a [[Elastic bandage|compression bandage]] above the wound<ref name="youtube.com">Breakfast News Program (September 27, 2012 [http://www.youtube.com/watch?v=jNt7qmkVKpM A teenage boy has survived being bitten by the world's most venomous snake.]. [[Sunrise (TV program)]] (official Youtube channel). Retrieved October 16, 2013.</ref> and the availability and administration of a polyvalent (broad-spectrum) [[antivenom]] in the local hospital (his friend was carrying a plastic tub containing the snake responsible) had been crucial to his survival. The fact that he even survived the first hour has amazed [[wildlife]] experts.<ref name="dailymail.co.uk">Shears, Richard (September 27, 2012 [http://www.dailymail.co.uk/news/article-2209256/Teenager-fights-life-bitten-snake-kill-100-men-ONE-DROP-venom.html Teenager fights for life after being bitten by world’s most deadly snake]. [[Daily Mail]]. Retrieved October 16, 2013.</ref> The boy was transferred to a hospital better equipped to handle the bite in the [[City of Newcastle]], where he was in a serious but stable condition and specialists were monitoring him closely. The police were involved to find out how the inland taipan got to this part of Australia. The snake was most likely a stolen/illegal pet and the boy tried to feed it.<ref name="smh.com.au"/><ref name="theaustralian.com.au"/><ref name="youtube.com"/><ref name="dailymail.co.uk"/><ref>Proudman, Dan (September 26, 2012) [http://www.theherald.com.au/story/361747/video-detectives-investigate-after-teen-bitten-by-deadly-taipan/ VIDEO: Detectives investigate after teen bitten by deadly taipan]. [[The Newcastle Herald]]. Retrieved October 16, 2013.</ref><ref>Petersen, Freya (September 27, 2012). [http://www.globalpost.com/dispatch/news/science/wildlife-news/120926/australia-sydney-snake-bite-worlds-deadliest-snake-inland-taipan-neurotoxin-antivenom Australia: Sydney teenager survives bite by world's deadliest snake, the inland taipan]. [[GlobalPost]]. Retrieved October 16, 2013.</ref> |
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In December 2013, reptile handler Scott Grant (age 40+) who was conducting a demonstration in front of 300 people at the annual building union's picnic in [[Portland, Victoria]] had just finished showing the crowd an inland taipan and was trying to put it into a bag when it struck him. The snake got tangled in a loose thread of the bag he was putting it into. “It came out of the bag and saw my hand and got a shock and bit it. I got bitten on the left-hand thumb”. Grant had been very professional in the incident, calmly telling people he thought he had been bitten before tying up the snake bag. He had then got into his utility and tied a bandage around his arm. However a few minutes later he was lying on the ground and [[Convulsion|convulsing]]. He was flown in a serious condition to [[Essendon Airport]] and driven to the [[Royal Melbourne Hospital]] where his condition was stabled and finally recovering over time. Luckily only a tiny amount of venom from the inland taipan had entered his body, and the adverse reaction he felt shortly after, was an [[Allergy|allergic]] one, presumably due to his past snake bites. His allergic reaction to the snake bite was being studied by the Australian Venom Research Unit at [[Melbourne University]].<ref>http://www.theage.com.au/victoria/picnicker-in-serious-condition-after-bite-by-rare-toxic-taipan-20131202-2ym4m.html</ref><ref>http://www.spec.com.au/blog/2013/12/04/taipan-handler-bitten-during-display/</ref><ref>http://www.standard.net.au/story/1952220/snake-handler-at-heightened-risk/?cs=73</ref><ref>http://www.standard.net.au/story/1949091/no-hard-feelings-for-taipan-bite-survivor/?cs=383</ref> |
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According to [[Rob Bredl]], a.k.a. "The Barefoot Bushman", in an isolated area of South Australia his father, Joe Bredl, was bitten while catching an inland taipan and barely survived. A more recent victim was his friend John Robinson, bitten while cleaning the inland taipan's cage at his Reptile Display on the [[Sunshine Coast, Queensland]]. He weathered the bite without antivenom but sustained considerable muscle damage as well as heart damage.<ref name= "Rob Bredl">[[Rob Bredl]] website . [http://web.archive.org/web/20071216111605/http://www.barefootbushman.com/ptaipan.htm THE TAIPANS]. (archived) barefootbushman.com. Retrieved November 15, 2013.</ref> |
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Almost all positively identified inland taipan bite victims have been [[Herpetology|herpetologists]] handling the snakes for study or snake handlers, such as people who catch snakes to extract their venom, or [[Zookeeper|keepers]] in [[wildlife park]]s, and all were treated successfully with [[antivenom]]. No recorded incidents have been fatal since the advent of the monovalent (specific) antivenom therapy,<ref name="INCHEM"/><ref name="billabongsanctuary.com.au"/><ref name="Barrett2003">{{cite journal |doi=10.1046/j.1442-2026.2003.00509.x |author=Barrett, Robyn and Little, Mark |year=2003 |month=Oct–Dec |title=Five years of snake envenoming in far north Queensland |journal=Emergency Medicine |volume=15 |issue=5–6 |pages=500–510|pmid=14992068 }}</ref> though it could take weeks to recover from such a severe bite.<ref name= "Welton, Ronelle Ellen">Welton, Ronelle Ellen (2005) PhD thesis. [http://eprints.jcu.edu.au/11938/4/02Chapters_1-3.pdf Proteomic and genomic characterisation of venom proteins from ''Oxyuranus'' species]. (microlepidotus). [[James Cook University]]. Retrieved November 15, 2013.</ref><ref name="theaustralian.com.au"/> |
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==References== |
==References== |
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{{reflist |
{{reflist}} |
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==Further reading== |
==Further reading== |
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*[[George Albert Boulenger|Boulenger, |
*[[George Albert Boulenger|Boulenger, G.A.]] 1896. ''Catalogue of the Snakes in the British Museum (Natural History). Volume III., Containing the Colubridæ (Opisthoglyphæ and Proteroglyphæ),...'' Trustees of the British Museum. (Taylor and Francis, printers.) London. xiv + 727 pp. + Plates I.- XXV. (''Pseudechis microlepidotus'', p. 332.) |
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*[[:fr:James Roy Kinghorn|Kinghorn JR]]. 1955. "A New Generic Name for Two Nominal Species of ''Pseudechis''." In: Herpetological Notes. No. 5. ''Rec. Australian Mus.'' '''23''' (5): 283-286. (''Parademensia, gen. nov.'', p. 285). |
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*[[William John Macleay|Macleay W]]. 1882. Description of two new species of Snakes. ''Proc. Linn. Soc. New South Wales'' '''6''': 811-813. (''Diemenia ferox'', pp. 812–813). |
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*[[Frederick McCoy|McCoy, F]]. 1879. ''Natural History of Victoria. Prodromus of the Zoology of Victoria; or, Figures and Descriptions of the Living Species of All Classes of the Victorian Indigenous Animals. Decade III.'' London: G. Robertson, publisher. (Melbourne: J. Ferres, government printer). 50 pp. + Plates 21–30. (''Diemenia microlepidota'', pp. 12–13 + Plate 23, Figures 2–3). |
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*[[Frederick McCoy|McCoy, F.]] 1879. ''Natural History of Victoria. Prodromus of the Zoology of Victoria; or, Figures and Descriptions of the Living Species of All Classes of the Victorian Indigenous Animals. Decade III.'' G. Robertson, publisher. London. (J. Ferres, government printer. Melbourne.) 50 pp. + Plates 21-30. (''Diemenia microlepidota'', pp. 12-13 + Plate 23, Figures 2-3.) |
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*[[Eric Worrell|Worrell E]]. 1963. ''Reptiles of Australia''. Sidney: Angus and Robertson. xv + 207 pp. ISBN 0207947414. |
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==External links== |
==External links== |
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{{commonscat-inline|Oxyuranus microlepidotus|''Oxyuranus microlepidotus''}} |
{{commonscat-inline|Oxyuranus microlepidotus|''Oxyuranus microlepidotus''}} |
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* [http://www.inchem.org/documents/pims/animal/taipan.htm International Programme on Chemical Safety, ''Oxyuranus microlepidotus'': Extended Review] |
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* [http://eprints.jcu.edu.au/11938/4/02Chapters_1-3.pdf James Cook University, Proteomic and genomic characterisation of venom proteins from ''Oxyuranus'' species] |
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* [http://www.reptilepark.com.au/animals.asp?catID=16&ID=112 Australian Reptile Park, Fierce Snake Fact File] |
* [http://www.reptilepark.com.au/animals.asp?catID=16&ID=112 Australian Reptile Park, Fierce Snake Fact File] |
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* [http://www.australiazoo.com.au/our-animals/amazing-animals/reptiles/?reptile=venomous_snakes&animal=fierce_snake Australia Zoo Fierce Snake Fact File] |
* [http://www.australiazoo.com.au/our-animals/amazing-animals/reptiles/?reptile=venomous_snakes&animal=fierce_snake Australia Zoo Fierce Snake Fact File] |
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* [http://www.youtube.com/watch?v=OzIzeFPCFWI&feature=youtu.be&t=1m12s Animal Weapons:Episode 1 – Chemical Warfare / Inland Taipan] (Source:[http://www.focalint.org/footage-and-content-gallery/directory/member/1104/absolutely-wild-visuals Absolutely Wild Visuals, stock footage library]) |
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[[Category:Taipans]] |
[[Category:Taipans]] |
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[[Category:Reptiles of Australia]] |
[[Category:Reptiles of Australia]] |
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[[Category:Animals described in 1879]] |
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Revision as of 00:18, 5 January 2014
| Inland taipan (fierce snake) | |
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| Species: | O. microlepidotus
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| Oxyuranus microlepidotus (F. McCoy, 1879)
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| Range of inland taipan (in red) | |
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The inland taipan (Oxyuranus microlepidotus), also commonly known as the small-scaled snake and fierce snake, is a species native to Australia and is regarded as the most venomous land snake in the world based on LD50 values in mice.[2] It is a species of taipan belonging to the Elapidae family. Although highly venomous, it is very shy and reclusive, and always prefers to escape from threat (the word "fierce" from its alternative name describes its venom, not its temperament).[3]
Appearance
The inland taipan is dark tan, ranging from a rich, dark hue to a brownish light-green, depending on season. Its back, sides and tail may be different shades of brown and grey, with many scales having a wide blackish edge. These dark-marked scales occur in diagonal rows so that the marks align to form broken chevrons of variable length that are inclined backward and downward. The lowermost lateral scales often have an anterior yellow edge. The dorsal scales are smooth and without keels. The round-snouted head and neck are usually noticeably darker than the body (glossy black in winter, dark brown in summer), the darker colour allowing the snake to heat itself while only exposing a smaller portion of the body at the burrow entrance. The eye is of average size with a blackish brown iris and without a noticeable coloured rim around the pupil.
It has 23 rows of dorsal scales at midbody, between 55 and 70 divided subcaudal scales, and one anal scale.
The inland taipan averages approximately 1.8 metres (5.9 ft) in total length, although larger specimens can reach total lengths of 2.5 metres (8.2 ft).[4]
Seasonal adaptation
Inland taipans adapt to their environment by changing the colour of the skin during seasonal changes. They tend to become lighter during summer and darker during the winter. This seasonal colour change serves the purpose of thermoregulation, allowing the snake to absorb more light in the colder months.
Geographic range
The inland taipan is native to the arid regions of central to eastern Australia. Its range extends from the southeast part of the Northern Territory into west Queensland. The snake can also be found north of Lake Eyre and to the west of the split of the Murray River, Darling River, and Murrumbidgee River.
Diet and behaviour
The inland taipan consumes mostly rodents, other small mammals, and birds. Unlike other venomous snakes that strike with a single accurate bite then retreat to wait for the prey to die, the inland taipan is known to deliver up to seven venomous bites in a single attack.
Reproduction
Inland taipan produce clutches of between one and two dozen eggs. The eggs hatch two months later. The eggs are usually laid in abandoned animal burrows and deep crevices. Reproduction rate depends in part on their diet. If there is not enough food, then the snake will reproduce less.
Venom
The inland taipan's venom consists of Taipoxin and protease enzymes. The average quantity of venom delivered by this species is 44 mg and the maximum dose recorded is 110 mg. The median lethal dose (LD50) for mice is 2 μg/kg (ppb) for pure Taipoxin[5] and 30 μg/kg (ppb) for the natural venom mixture.[6] Its venom consists mostly of neurotoxins. Almost all positively identified inland taipan bite victims have been herpetologists handling the snakes for study, and all were treated successfully with antivenom—no recorded incidents have been fatal since the advent of the specific antivenom therapy.[7][8]
Gallery
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Brown-coloured (winter) -
Olive-coloured (summer)
References
- ^ The Reptile Database. www.reptile-database.org.
- ^ LD50, seanthomas.net (December 1999).
- ^ "Our Animals – Reptiles – Venomous Snakes – Fierce Snake". Australia Zoo. Retrieved 2009-05-21.
- ^ "Fierce Snake (Inland Taipan)". Australian Reptile Park. Retrieved 2009-11-07.
- ^ Fohlman, J.; Eaker, D.; Karlsoon, E. and Thesleff, S. (1976). "Taipoxin, an extremely potent presynaptic neurotoxin from the venom of the australian snake taipan (Oxyuranus s. scutellatus). Isolation, characterization, quaternary structure and pharmacological properties". Eur. J. Biochem. 68 (2): 457–69. doi:10.1111/j.1432-1033.1976.tb10833.x. PMID 976268.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ "Strength of Venom". School of Chemistry, University of Bristol. Retrieved 2008-02-29.
- ^ Barrett, Robyn (2003). "Five years of snake envenoming in far north Queensland". Emergency Medicine. 15 (5–6): 500–510. doi:10.1046/j.1442-2026.2003.00509.x. PMID 14992068.
{{cite journal}}: Unknown parameter|coauthors=ignored (|author=suggested) (help); Unknown parameter|month=ignored (help) - ^ White, Julian (November 1991). "Oxyuranus microlepidotus". Chemical Safety Information from Intergovernmental Organizations. Retrieved 24 July 2009.
Further reading
- Boulenger, G.A. 1896. Catalogue of the Snakes in the British Museum (Natural History). Volume III., Containing the Colubridæ (Opisthoglyphæ and Proteroglyphæ),... Trustees of the British Museum. (Taylor and Francis, printers.) London. xiv + 727 pp. + Plates I.- XXV. (Pseudechis microlepidotus, p. 332.)
- McCoy, F. 1879. Natural History of Victoria. Prodromus of the Zoology of Victoria; or, Figures and Descriptions of the Living Species of All Classes of the Victorian Indigenous Animals. Decade III. G. Robertson, publisher. London. (J. Ferres, government printer. Melbourne.) 50 pp. + Plates 21-30. (Diemenia microlepidota, pp. 12-13 + Plate 23, Figures 2-3.)
External links
Media related to Oxyuranus microlepidotus at Wikimedia Commons