Collett's snake

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Collett's snake
Collett's Snake.JPG
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Elapidae
Genus: Pseudechis
Species: P. colletti
Binomial name
Pseudechis colletti
Boulenger, 1902

The Collett's snake (Pseudechis colletti) – also known as the Down's tiger snake, Collett's black snake or Colletts cobra – is a venomous snake native to Australia. Although the Collett's snake is not as venomous as other Australian snakes, it is capable of delivering a fatal bite, ranking nineteenth in the world's most venomous snakes.[1]

Taxonomy[edit]

Collett's snake is one of several species in the genus Pseudechis commonly known as black snakes. A study of mitochondrial DNA showed it to be most closely related to the blue-bellied black snake (P. guttatus), with the Papuan black snake (P. papuanus) as the next closest relative to the pair.[2]

Belgian naturalist George Albert Boulenger described the species in 1902,[3] naming it in honour of Norwegian zoologist Robert Collett.[4] A young snake had been collected by Collett, and Boulenger had noted its scale pattern to be distinct from the Papuan black snake.[3]

Description[edit]

The most colourful member of the black snake genus Pseudechis, it has dark brown to black upperparts, with pink or cream banding and sides, and pale yellow to orange underparts.[5] The irregular bands are usually cross-shaped and are generally an orange-red colour. The Collett's underbelly is normally the same colour as its bands, but may have varied discolourisations or discoloured patches. Juveniles are usually the same colour as adults but generally have brighter shades and contrast more. It is similar in physical structure (but not appearance) to the red-bellied black snake.

The Collett's snake are usually found between 1.8 – 2.2 metres. Males can reach up to 2.6 metres in length, while females can reach up to 2.1 metres. They are usually 30 centimetres in length at birth.

Venom[edit]

Previously thought to be only moderately venomous to people, Collett's snake is now known to have been responsible for severe envenomation, with cases proceeding to rhabdomyolysis and acute renal failure. Toxicity and symptoms of the venom resemble that of the mulga snake (P. australis). Early symptoms include nausea, vomiting, abdominal pain, diarrhoea and headache, an anticoagulant coagulopathy, with risk of rhabdomyolysis and acute renal failure within 24 hours if fluid replacement and black snake antivenom are not given.[6] Despite the danger, its attractive markings have led it to being a popular snake in captivity.[6]

The venom produced by the Collett's snake is similar to the Papuan black snake's and mulga snake's venom.[7] The venom is cytotoxic and has haemolytic activity. Neurotoxins may also be found in its venom as well. Collett's produce around about 30 milligrams of venom in one strike. Black snake or tiger snake anti-venom can be administered. It is the world's nineteenth most venomous snake.[1]

Distribution and habitat[edit]

Collett's snake is found in central western Queensland, and is diurnal.[5] It is primarily found to the west of Queensland and spreading from the north to south. They are found in dry-barren areas or plains.

Behaviour[edit]

Diet[edit]

The Collett's main diet consists of amphibians, reptiles and small mammals. Cannibalism is also known to occur in Collett's snakes.

Reproduction[edit]

Mating occurs from early August to late October. Collett's snakes are egg layers and may lay up to 20 eggs in a clutch.[5] Reproduction in captivity is known to be highly successful.

References[edit]

  1. ^ a b Scott Eipper. "Collett's Snake". Retrieved 2007-12-28. 
  2. ^ Wüster, W.; A.J. Dumbrell; C. Hay; C.E. Pook; D.J. Williams & B.G. Fry (2005). "Snakes across the Strait: Trans-Torresian phylogeographic relationships in three genera of Australasian snakes (Serpentes: Elapidae: Acanthophis, Oxyuranus and Pseudechis)." (PDF). Molecular Phylogenetics and Evolution 34(1): 1–14. 
  3. ^ a b Boulenger, George Albert (1902). "Description of a new snake of the genus. Pseudechis from Queensland". Annals and Magazine of Natural History. 7 (10): 494–95. 
  4. ^ Bo Beolens; Michael Watkins; Michael Grayson (2009). The eponym dictionary of mammals. JHU Press. p. 82. ISBN 0-8018-9304-6. 
  5. ^ a b c Gow, Graeme (1989). Complete Guide to Australian Snakes. Angus and Robertson. p. 121. ISBN 0-207-15806-1. 
  6. ^ a b Isbister, G. K.; Hooper, M. R.; Dowsett, R.; Maw, G.; Murray, L.; White, J. (2005). "Collett's snake (Pseudechis colletti) envenoming in snake handlers". QJM. 99 (2): 109–15. PMID 16434468. doi:10.1093/qjmed/hcl007. 
  7. ^ Australian Venom Research Unit. "Collett's Snake". Retrieved 2007-12-28.