taipan

Taipans
Inland Taipan (Oxyuranus microlepidotus)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Elapidae
Genus:	Oxyuranus
Species
O. scutellatus O. s. scutellatus (coastal taipan) O. s. canni (Papuan taipan) O. microlepidotus (inland taipan) O. temporalis (Central Ranges taipan)

The taipans are a genus of large, fast, highly venomous Australasian snakes of the elapid family.

Overview

A coastal taipan.

The taipan was named by Donald Thomson after the word used by the Wik-Mungkan Aboriginal people of central Cape York Peninsula, Queensland, Australia.^[1]

The three known species are: the coastal taipan (Oxyuranus scutellatus), the inland taipan (Oxyuranus microlepidotus) and a recently discovered third species, the Central Ranges taipan (Oxyuranus temporalis).^[2] The coastal taipan has two subspecies: the coastal taipan (O. s. scutellatus), found along the northeastern coast of Queensland, and the Papuan taipan (O. s. canni), found on the southern coast of Papua New Guinea. Their diets consist primarily of small mammals, especially rats and bandicoots.

One species, the inland taipan (O. microlepidotus), which is endemic to Australia, has the most toxic venom of any terrestrial snake species worldwide. Pseudonaja textilis intervenes between the inland and coastal taipan (O. scutellatus) which has the third-most toxic venom of any land snake. O. temporalis may be even more lethal, but has been less researched than other species of this genus.^[3] Toxicity is measured as LD₅₀ in mg/kg for mice. Venom yield also must be taken into account. The venom clots the victim's blood, blocking blood vessels and using up clotting factors. It is also highly neurotoxic. There were no known survivors of a taipan bite before an antivenom (antivenene) was developed and, even then, victims often require extended periods of intensive care.

The coastal taipan (O. scutellatus) is among the third-most venomous land snake in the world based on LD₅₀, and arguably the largest venomous snake in Australia. Its venom contains primarily taicatoxin, a highly potent neurotoxin, and is known to cause hemolytic and coagulopathic reactions.^[4] Death can occur as early as 30 minutes after being bitten by it.^[4] The untreated envenomation mortality rate from this species can near 100%.^[4] The danger posed by the coastal taipan was brought to Australian public awareness in 1950, when young herpetologist Kevin Budden was fatally bitten in capturing the first specimen available for antivenom research. The coastal taipan is often considered to be one of the deadliest species in the world.^[5]

Description

Taipans can grow to 3 meters long.^[6] The coastal taipan is usually pale to dark brown in color, fading to a lateral cream, although juveniles are lighter in color. The Papuan taipan is black or purplish-gray, with a copper-colored stripe on its back. They are often found in sugar fields due to an abundance of rats, their main food source. They feed on these two or three times a week.

In several aspects of morphology, ecology and behavior, the coastal taipan is strongly convergent with an African elapid, Dendroaspis polylepis (the black mamba).^[7]

References

External links

• Barnett, Brian. "Keeping and Breeding the Coastal Taipan (Oxyuranus scutellatus)." Journal of the Victorian Herpetological Society, 10 (2/3), 1999 (pages 38–45).
• Williams, David. "The Death of Kevin Budden." David Williams' Australian Herpetology Online, January 2004.
• "Coastal Taipan," Reptiles Down Under, www.reptilesdownunder.com/
• "Inland Taipan," Reptiles Down Under, www.reptilesdownunder.com/