Austrelaps

Austrelaps
Austrelaps labialis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Vertebrata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Elapidae
Genus:	Austrelaps Worrell, 1963

Austrelaps is a genus of venomous elapid snakes native to the relatively fertile, temperate, southern and eastern part of the Australian continent. Three species are currently recognized, with no subspecies. They are commonly called copperheads or Australian copperheads. They are not closely related to the American copperhead, Agkistrodon contortrix.

Description

The three species of Australian copperheads, i.e., the pygmy, highlands, and common copperheads, vary in size. The pygmy copperhead is 60 cm (2.0 ft) long, and lives in South Australia and on Kangaroo Island. The highlands copperhead is 1.25 m (4.1 ft) in length and lives in northern Victoria to southern New South Wales. The common copperhead reaches 1.75 m (5 ft 9 in) in length and lives in southern Victoria into Tasmania.

Australian copperheads are usually of medium size, 1.4–1.7 m (4.6–5.6 ft),^[1] only rarely being more than 1.8 m (5.9 ft) long, and have a moderate build. Their colour varies a great deal, from a coppery mid-brown to yellowish, reddish, grey or even black, depending on the individual. The copper head colouring that gave rise to the common name is sometimes present, sometimes not. Some individuals also have visible markings just behind the head. Perhaps in consequence of this great variation, it was not realised until the second half of the 20th century that there were in fact three different species. Venom toxicity has been measured at 0.5 mg/kg subcutaneous, at least for the lowlands copperhead.

Common names

Common names include copperhead, diamond snake, superb snake, lowland snake, and highland snake.

Distribution and habitat

Copperheads are well adapted to cooler climates; they remain active after most reptiles have become dormant, and are the first to resume hunting at the end of winter. Their favoured habitat is near water. While they are moderately uncommon elsewhere, they congregate in substantial numbers where conditions are suitable.

Behaviour

Copperheads are diurnal at most times of year, but switch to night hunting in hot weather.

Diet

Copperheads are very much at home in the water; they swim well and often hunt tadpoles. They are generalised carnivores and will take any suitably sized prey—including their own young—but the major diet item is frogs. Where frogs are common, so too are copperheads, and other snakes tend to be rare.

Breeding

Breeding starts in spring, and females give birth to about 14 live young, each a little under 20 cm (7.9 in) long, in late summer.

Venom

Like all elapids (members of the family Elapidae), Australian copperheads have hollow, fixed fangs mounted at the front of the jaw. They are shy and retiring by nature, and prefer to escape rather than fight where escape is possible, and their venom is, by Australian standards, only moderately toxic (equal on a per-mg basis to that of the Indian cobra). Nevertheless, they deliver a substantial quantity of venom, and a copperhead bite left untreated can easily kill a healthy adult human. There is no specific copperhead antivenom; however, tiger snake antivenom is effective.

Species

Species	Authority	Common name	Geographic range
A. labialis	(Jan, 1859)	pygmy copperhead	Australia (South Australia)
A. ramsayi	(Krefft, 1864)	highlands copperhead	Australia (New South Wales, Victoria)
A. superbus	(Günther, 1858)	lowlands copperhead	Australia (New South Wales, South Australia, Tasmania, Victoria)

References

1. Kindersley, Dorling (2001,2005). Animal. New York City: DK Publishing. ISBN 0-7894-7764-5. Check date values in: |date= (help)

External links

• Genus Austrelaps at The Reptile Database
• Integrated Taxonomic Information System - Austrelaps