Pseudonaja

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Pseudonaja
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Elapidae
Genus: Pseudonaja
Günther, 1858

Pseudonaja is a genus of venomous elapid snakes native to Australia. Members are known commonly as brown snakes and are considered to be one of the most dangerous snakes in the country; even young snakes are capable of delivering a fatal envenomation to a human.

Despite its name, the King Brown Snake (Pseudechis australis) is not a brown snake, but a member of the Pseudechis genus, commonly known as the Black Snakes.

Species[edit]

A photo of a Dugite taken in Joondalup, Western Australia.

Toxicity[edit]

Brown snakes are easily alarmed and may bite if approached closely, handled or threatened. Sudden, early collapse is often a feature of brown snake envenomation. A prominent effect of envenomation is venom-induced consumption coagulopathy and this can lead to death. Renal damage may also rarely occur.[3]

Other clinical signs include: abdominal pain, breathing and swallowing difficulty, convulsions, ptosis, hemolysis, hypotension from depression of myocardial contractility, renal failure. Notably rhabdomyolysis is not a feature of envenomation by brown snakes.

The Eastern Brown Snake (Pseudonaja textilis) is the most toxic member of the genus and is considered by some to be the second most toxic land snake in the world, after the Inland Taipan (which is also found in Australia). The western brown snake is the tenth most venomous snake in the world.

Brown snakes can easily harm animals and livestock as well.

The venom fangs of the Pseudonajas are very short and the average yield of venom per bite is relatively low - for P. textilis, P. nuchalis und P. affinis about 4 bis 6,5 mg dry weight of the venom.[4] Therefore most of the bites end up without serious medical consequences. Despite of its toxicitiy the smallest Pseudonaja P. modesta can even be considered as harmless.[5] Bites by the bigger Pseudonajas, especially P. textilis and P. nuchalis are known for causing serious toxication or even fatalities; children are particularly at risk.[4]

References[edit]

  1. ^ (Skinner, 2009)
  2. ^ (Skinner, 2009)
  3. ^ Isbister, Geoff; et al. (2006). "Snake Bite: Current Approach to Treatment". Australian Prescriber 29 (5): 125–129. 
  4. ^ a b Mirtschin, P. J., G. R. Crowe und R. Davis: Dangerous Snakes Of Australia. In: P. Gopalakrishnakone, L. M. Chou: Snakes of Medical Importance. Venom and Toxin Research Group, National University of Singapore, 1990, page 49–77.
  5. ^ Mirtschin, P. J., G. R. Crowe und R. Davis: Dangerous Snakes Of Australia. In: P. Gopalakrishnakone, L. M. Chou: Snakes of Medical Importance. Venom and Toxin Research Group, National University of Singapore, 1990, pages 49–77, especially page 49
  • SKINNER, A. (2009), A multivariate morphometric analysis and systematic review of Pseudonaja (Serpentes, Elapidae, Hydrophiinae). Zoological Journal of the Linnean Society, 155: 171–197. doi: 10.1111/j.1096-3642.2008.00436.x