Venomous snake

Source: Wikipedia, the free encyclopedia.
For the video game character, see
Venom Snake
.
The lateral view of a king cobra's skull showing fangs

Venomous snakes are

hemotoxic
properties. There are about 600 venomous snake species in the world.

Evolution

Main article: Evolution of snake venom

The evolutionary history of venomous snakes can be traced back to as far as 28 million years ago.

prey immobilization and self-defense and is usually delivered through highly specialized teeth, hollow fangs, directly into the bloodstream or tissue of the target. Evidence has recently been presented for the Toxicofera hypothesis, that venom was present (in small amounts) in the ancestors of all snakes (as well as several lizard families) as "toxic saliva" and evolved to extremes in those snake families normally classified as venomous by parallel evolution. The Toxicofera hypothesis further implies[according to whom?] that "nonvenomous" snake lineages have either lost the ability to produce venom (but may still have lingering venom pseudogenes), or actually do produce venom in small quantities, likely sufficient[according to whom?
] to help capture small prey but causing no harm to humans when bitten.

Taxonomy

There is not a single or special

taxonomic group for venomous snakes. Venom is known in several families. This has been interpreted[by whom?] to mean venom in snakes originated more than once as the result of convergent evolution
. Around a quarter of all snake species are identified as being venomous.

Family Description
Atractaspididae (atractaspidids) Purple-glossed snakes, centipede eaters, burrowing asps, Revoil's short snake, Chilorhinophis, Hypoptophis, Homoroselaps, Macrelaps, Micrelaps, and more.
Colubridae (colubrids) Most are harmless, but others have potent venom and at least five species, including the boomslang, have caused human fatalities.
Elapidae (elapids)
king cobras, cobras
and more.
Viperidae (viperids)
pit vipers, including rattlesnakes, lanceheads and copperheads and cottonmouths
.

Terminology

Venomous snakes are often said to be

poisonous toads the snakes eat.[2] Similarly, certain garter snakes from Oregon can retain toxins in their livers from ingesting rough-skinned newts.[3]

Danger

The world's most venomous snake, based on LD50, is the inland taipan of Australia.

Toxicity issues

Venom toxicities are compared by looking at the

vein (IV), muscle or peritoneum (IP). Smaller murine LD50 values indicate venoms that are more toxic, and there have been numerous studies on snake venom with a variability of potency estimates.[4] SC LD50 is considered[by whom?] the most applicable to actual bites as only vipers with large fangs (such as large specimens from the genera Bitis, Bothrops, Crotalus, or Daboia) are capable of a truly intramuscular bite, snakebites rarely cause IV envenomation, and IP envenomation is even rarer. Measurements of LD50 using dry venom mixed with 0.1% bovine serum albumin in saline are more consistent than the results obtained using saline alone. As an example, the venom of the eastern brown snake has a murine LD50 (SC) of 41 μg/kg when measured in 0.1% bovine serum albumin in saline; when saline alone is used, the value is 53 μg/kg.[5]

cardiac cell culture[6][12][13] show that venom of the inland taipan
is the most toxic among all snakes.

Most venomous snakes of the world[5][8][14]
Snake Region
subcutaneous injection LD50
intravenous injection LD50
0.1% bovine serum albumin in saline in saline
Inland taipan Australia 0.01 mg/kg 0.025 mg/kg N/A
Dubois' sea snake
 Coral Sea, Arafura Sea, Timor Sea, Tar River, and Indian Ocean N/A 0.044 mg/kg N/A
Eastern brown snake Australia, Papua New Guinea, Indonesia 0.041 mg/kg 0.053 mg/kg 0.01 mg/kg
Yellow-bellied sea snake
 Tropical oceanic waters N/A 0.067 mg/kg N/A
Peron's sea snake
Gulf of Siam, Taiwan Strait, Coral Sea Islands
, and other places		 N/A 0.079 mg/kg N/A
Coastal taipan Australia 0.064 mg/kg 0.105 mg/kg 0.013 mg/kg
Many-banded krait Mainland China, Taiwan, Vietnam, Laos, Burma N/A 0.108 mg/kg 0.061 mg/kg
Black-banded sea krait eastern coast of the Malay Peninsula and Brunei, and in Halmahera, Indonesia N/A 0.111 mg/kg N/A
Black tiger snake Australia 0.099 mg/kg 0.131 mg/kg N/A
Mainland tiger snake Australia 0.118 mg/kg 0.118 mg/kg 0.014 mg/kg
Western Australian Tiger snake Australia 0.124 mg/kg 0.194 mg/kg N/A
Beaked sea snake
 Tropical Indo-Pacific 0.164 mg/kg 0.1125 mg/kg N/A

Other factors

Indian Subcontinent

The toxicity of snake venom, based on laboratory tests conducted on mice, is sometimes used to gauge the extent of danger to humans, but this is not enough. Many venomous snakes are specialized predators whose venom may be adapted specifically to incapacitate their preferred prey.[15] A number of other factors are also critical in determining the potential hazard of any given venomous snake to humans, including their distribution and behavior.[16][17] For example, while the inland taipan is regarded as the world's most venomous snake based on LD50 tests on mice, it is a shy species and rarely strikes, and has not caused any known human fatalities. On the other hand, India's Big Four (Indian cobra, common krait, Russell's viper, and saw-scaled viper), while less venomous than the inland taipan, are found in closer proximity to human settlements and are more confrontational, thus leading to more deaths from snakebite. In addition, some species, such as the black mamba and coastal taipan, occasionally show some aggression, generally when alarmed or in self-defence, and then may deliver fatal doses of venom, resulting in high human mortality rates.[18][19]

See also

References

  1. PMID 24646522
  2. ISBN 978-0-520-21056-1
    .
  3. S2CID 14274035
    .
  4. S2CID 86568032. Archived from the original
    (PDF) on 2010-06-02. Retrieved 2009-09-26.
  5. ^
    PMID 524395
    .
  6. ^ a b Fry, Bryan Archived 2014-04-19 at the Wayback Machine (February 08, 2005) Most Venomous Archived 2014-10-17 at the Wayback Machine,"Q;I was wondering what snakes venom is the most potent to humans A:Drop for drop it is the inland taipan (Oxyuranus microlepidotus), which has a venom more toxic than any other land snake or even the sea snakes." venomdoc.com Forums, Retrieved April 17, 2014
  7. PMID 4818649
    .
  8. ^ a b Fry, B. G. (February 24, 2012). "Snakes Venom LD50 – List of the Available Data and Sorted by Route of Injection". venomdoc.com. Archived from the original on April 13, 2012. Retrieved October 14, 2013.
  9. ^ *"Which snakes are the most venomous?". Australian Venom Research Unit, University of Melbourne. August 25, 2007. Archived from the original on June 26, 2014. Retrieved October 14, 2013.
  10. ^
  11. Belcher's sea snake
    )
  12. National Geographic Channel
    . Retrieved April 17, 2014. (starting at 44 min 33 s): "Among the reptiles tested, the most toxic venom belongs to inland taipan, killing over 60% of heart cells in the first 10 minutes
  13. National Geographic Channel. Archived from the original
    on February 10, 2011. Retrieved April 17, 2014. (starting at 1 min 49 s): "They have the most toxic venom towards humans then any other snake in the world
  14. ^ "Facts and Figures: World's Most Venomous Snakes". Australian Venom Research Unit, University of Melbourne. January 11, 2014. Archived from the original on October 11, 2014. Retrieved July 14, 2014.
  15. ^ "What is an LD50 and LC50". 2018-12-31.
  16. ^ "Most venomous snakes". Reptile Gardens. Archived from the original on May 8, 2017. Retrieved October 13, 2014.
  17. ^ Walls, Jerry G. "Deadly Snakes: What are the world's most deadly venomous snakes?". Reptiles. Retrieved November 5, 2013.
  18. ^ Davidson, Terence. "Immediate First Aid – Black Mamba". University of California, San Diego. Archived from the original on 2023-07-25. Retrieved 2010-05-12.
  19. ^ "Immediate First Aid for bites by Australian taipan or common taipan".

External links

Wikivoyage has a travel guide for Venomous snakes.
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