Red-bellied black snake
|Red-bellied black snake|
|Red-bellied black snake at |
Lane Cove National Park, Sydney,
New South Wales, Australia
|Range of red-bellied black snake (in red)|
The red-bellied black snake (Pseudechis porphyriacus) is a species of elapid snake native to eastern Australia. Though its venom is capable of causing significant morbidity, a bite from it is not generally fatal and is less venomous than other Australian elapid snakes. It is common in woodlands, forests and swamplands of eastern Australia. It is one of Australia's best-known snakes, as it is common in urban areas along the eastern coast of Australia. It has an average total length (including tail) of 1.5 to 2 metres (4 ft 11 in to 6 ft 7 in).
The red-bellied black snake was described by George Shaw in Zoology of New Holland (1794), placing it in the genus Coluber. He wrote, "This beautiful snake, which appears to be unprovided with tubular teeth or fangs, and consequently not of a poisonous nature, is three, sometimes four, feet in nature." The species name is derived from the Ancient Greek porphyreus, which can mean "dark purple", red-purple" or "beauteous". It was the first Australian elapid snake described. The accompanying illustration was attributed to James Sowerby, but is regarded as being produced from drawings by John White. The syntype is presumed lost. French naturalist Bernard Germain de Lacépède described it under the name Trimeresurus leptocephalus in 1804. His countryman René Lesson described it as Acanthophis tortor in 1826.
Snake expert Eric Worrell analyzed the skulls of the genus and found that of the red-bellied black snake to be the most divergent. its position as an early offshoot from the rest of the genus has been confirmed genetically.
Raymond Hoser described two subspecies in 2003: Pseudechis porphyriacus eipperi the Atherton Tableland and surrounds in North-east Queensland, which he noted was smaller, rarely attaining 2 m (7 ft) and had a white or pale pink rather than red belly, and Pseudechis porphyriacus rentoni from southeastern South Australia, which has a variable-coloured (often orange or even blueish-tinged) belly. He added that both were disjunct from the main red-bellied black snake population, and as the distinguishing traits of P. porphyriacus rentoni were not consistent then location was the most reliable way of identifying it. These subspecies have not been recognized by other authors. Hoser has been criticized by Hinrich Kaiser and colleagues for identifying some taxa on location alone.
As well as red-bellied black snake, the species has been called common black snake, redbelly and RBBS.
The red-bellied black snake is glossy black on the dorsal surface and red, crimson or pink in colour on the lower sides and belly. The snout is often a lighter brown colour. It is a relatively medium species of snake reaching up to 2 metres (6 ft 7 in) in total length (including tail), with an extreme example measuring 2.5 metres (8 ft 2 in), although an average sized specimen would be closer to 1.4 metres (4 ft 7 in). Like all Elapid snakes it is front fanged. It has 17 mid-body scale rows. Juveniles are similar to the eastern small-eyed snake, with which it can be easily confused.
The red-bellied black snake can have a strong smell, which some field experts have used to find the snakes in the wild.
Distribution and habitat
The red-bellied black snake is native to the east coast of Australia. It can be found in the urban forest, woodland, plains and bushland areas of the Blue Mountains, Canberra, Sydney, Brisbane, Melbourne, Cairns and Adelaide. The Macquarie Marshes marks a western border to their distribution in New South Wales. It is most commonly seen close to dams, streams, billabongs and other bodies of water, although they can venture up to 100 m away. In particular, the red-bellied black snake prefers areas of shallow water with tangles of water plants, logs or debris.
Red-bellied black snakes have multiple places they can hide in their habitat including logs, old mammal burrows, and grass tussocks. They can flee into water and hide there, with one report of one staying submerged for 23 minutes. When swimming they may have the whole head or the nostrils above the water's surface. Within their habitat, red-bellied black snakes appear to have ranges or territories that they are familiar with and generally remain within. A 1987 field study in three New South Wales localities found that they varied widely, from 0.02 to 40 hectares in size.
The red-bellied black snake is generally not an aggressive species. However, when provoked, it will recoil into its striking stance as a threat, but will try to escape at the first opportunity. It is generally active by day, though nighttime activity has occasionally been recorded. When not hunting or basking it may be found beneath timber, rocks and rubbish or down holes and burrows.
Snakes are active when their body temperatures are between 28 and 31 C. They also thermoregulate by basking in warm sunny spots in the cool early morning and rest in shade in the middle of hot days, and may reduce their activity in hot dry weather in late summer and autumn. In July 1949, six large red-bellied black snakes were found hibernating under a concrete slab in marshland in Woy Woy, New South Wales. Groups of up to 6 hibernating red-bellied black snakes have been recorded from under concrete slabs around Mount Druitt and Rooty Hill in western Sydney.
The diet of red-bellied black snake primarily consists of frogs, but it also preys on reptiles and small mammals. They also eat other snakes, including those of their own species. Fish are hunted in water. As red-bellied black snakes grow and mature, they continue to eat the same size prey but add larger animals as well. Although they prefer live food, red-bellied black snakes have been reported eating frogs squashed by cars.
They are susceptible to cane toad toxins. The introduction of Cane toads in Australia dates to 1935, when cane toads (Rhinella marina) were introduced in an attempt at biological control of native beetles which were damaging sugar cane fields (a non-native plant). The intervention failed, mostly because the toads are on the ground while the beetles feed on leaves at the top of the plant. One research study concluded that in less than 75 years the red-bellied black snake had evolved in toad-inhabited regions of Australia to have increased resistance to toad toxin and decreased preference for toads as prey.
In spring, male red-bellied black snakes often engage in ritualised combat for anywhere from 2 to 30 minutes, even attacking other males already mating with females. They wrestle vigorously but rarely bite, and engage in head-pushing contests, where each snake tries to push his opponents' head downward with his chin.
Red-bellied black snakes are ovoviviparous; that is, they give birth to live young in individual membranous sacs. The young, numbering between eight and forty, emerge from their sacs very shortly after birth, and have an average length of about 12.2 centimetres (4.8 in).
The red-bellied black snake accounted for 16% of identified snakebite victims in Australia between 2005 and 2015, with no deaths recorded. Its venom consists of neurotoxins, myotoxins, coagulants and also has haemolytic properties. Bites from red-bellied black snake are rarely life-threatening, but require immediate medical attention. Symptoms of systemic envenomation—including nausea, vomiting, headache, abdominal pain, diarrhoea or diaphoresis—were thought to be rare, but a 2010 review found they occurred in most bite victims. Most people also go on to develop an anticoagulant coagulopathy in a few hours. This is characterised by a raised aPTT, and subsides over 24 hours. It resolves quickly with antivenom. A few people go on to develop a myotoxicity and associated generalised muscle pain and occasionally weakness, which may last for up to 7 days. The red-bellied black snake is the most commonly reported species responsible for envenomed dogs in New South Wales. In 2006, a 12 year old golden retriever suffered rhabdomyolysis and acute renal failure secondary to a red-bellied black snake bite.
Tiger snake antivenom is used to treat bites. While black snake antivenom can be used, tiger snake antivenom can be used at a lower dose. The smaller dose is cheaper to produce, and is less likely to cause a reaction in the patient. Patients may suffer anosmia.
Red-bellied black snakes adapt readily to captivity and live on a supply of mice.
- Australian Biological Resources Study (26 August 2013). "Species Pseudechis porphyriacus (Shaw, 1794)". Australian Faunal Directory. Canberra, Australian Capital Territory: Department of the Environment, Water, Heritage and the Arts, Australian Government. Retrieved 17 May 2017.
- Swan, Steven K.; Wilson, Gerry (2010). A Complete Guide to Reptiles of Australia (3rd ed.). Chatswood, New South Wales: New Holland Publishers. ISBN 978-1-877069-76-5.[page needed]
- Tab. X of: Zoology and botany of New Holland and the isles adjacent / the zoological part by George Shaw, the botanical part by James Edward Smith; the figures by James Sowerby.
- Pseudechis porphyriacus at the Reptarium.cz Reptile Database
- Shaw, George (1794). Zoology of New Holland. London, United Kingdom: J. Sowerby. pp. 27–28.
- Liddell, Henry George; Scott, Robert (1980) . A Greek-English Lexicon (abridged ed.). Oxford, United Kingdom: Oxford University Press. p. 579.
- Williams, David; Wüster, Wolfgang; Fry, Bryan Grieg (2006). "The good, the bad and the ugly: Australian snake taxonomists and a history of the taxonomy of Australia's venomous snakes". Toxicon. 48 (7): 919–30. doi:10.1016/j.toxicon.2006.07.016. PMID 16999982.
- Picture Library State Library of Victoria
- Lacépède, B.G.E. (1804). "Mémoire sur plusieurs animaux de la Nouvelle-Hollande dont la description n'a pas encore été publiée". Annales du Muséum National d'Histoire Naturelle. Paris. 4: 184–211 ; [pl. 56 fig. 1].
- Lesson, R.P. (1826). "Reptiles.". In Duperrey, L.I. Voyage Autour du Monde, Exécuté par Ordre du Roi, sur la Corvette de sa Majesté, La Coquille, Pendant les Années 1822, 1824 et 1825. Zoologie, Atlas. Paris: Arthus Bertrand.
- Wagler, Johann Georg (1830). Natürliches System der Amphibien, mit vorangehender Classification der Säugethiere und Vogel (in German). Munich, Germany: Cotta'schen. p. 171.
- Worrell, Eric (1961). "Herpetological Name Changes". West Australian Naturalist 8: 18–27. "Archived copy" (PDF). Archived from the original (PDF) on 2012-03-19. Retrieved 2012-01-17.
- Maddock, Simon T.; Childerstone, Aaron; Fry, Bryan Grieg; Williams, David J.; Barlow, Axel; Wüster, Wolfgang (2017-02-01). "Multi-locus phylogeny and species delimitation of Australo-Papuan blacksnakes (Pseudechis Wagler, 1830: Elapidae: Serpentes)". Molecular Phylogenetics and Evolution. 107: 48–55. doi:10.1016/j.ympev.2016.09.005.
- Hoser, Raymond (2003). "A re-assessment of the taxonomy of the Red-bellied Black Snakes (Genus Pseudechis) with the descriptions of two new subspecies" (PDF). Boydii — Journal of the Herpetological Society of Queensland (Autumn (May)): 15–18.
- "Best Practices: In the 21st Century, Taxonomic Decisions in Herpetology are Acceptable Only When Supported by a Body of Evidence and Published via Peer-Review" (PDF). Herpetological Review. 44 (1): 8–23. 2013.
- Beatson, Cecilie (5 May 2017). "Red-bellied Black Snake". Australian Museum website. Australian Museum. Retrieved 19 May 2017.
- Australian Broadcasting Corporation. "Massive red-bellied black snake surprises Newcastle wrangler called in to remove it". Retrieved 2014-10-02.
- Reptile Park. "Red Bellied Black Snake". Archived from the original on 2008-01-03. Retrieved 2007-12-28.
- Greer 1997, p. 163.
- Shine, Richard (1987). "Intraspecific variation in thermoregulation, movements and habitat use by Australian blacksnakes, Pseudechis porphyriacus (Elapidae)" (PDF). Journal of Herpetology. 21 (3): 165–77. doi:10.2307/1564479.
- Gilbert, P.A. (1935). "The black snake". Proceedings of the Royal Zoological Society of New South Wales. 55: 35–37.
- Greer 1997, p. 139.
- Bain, Libby. "The Australian Reptile Park and Wildlife Sanctuary". Red-bellied Black Snake – Pseudechis porphyriacus. Australian Reptile Park. Retrieved 1 July 2011.
- Greer 1997, p. 140.
- Ormsby, A.I. (1952). "Notes on snake hibernation in New South Wales". Proceedings of the Royal Zoological Society of New South Wales. 71: 25–27.
- Hoser, Raymond T. (1980). "Further records of aggregations of various species of Australian Snake". Herpetofauna. 12 (1): 16–22.
- Greer 1997, p. 145.
- Greer 1997, p. 147.
- Phillips BL, Shine R (2006). "An invasive species induces rapid adaptive change in a native predator: cane toads and black snakes in Australia". Proc. Biol. Sci. 273 (1593): 1545–50. doi:10.1098/rspb.2006.3479. PMC . PMID 16777750.
- Shine, Richard; Grigg, Gordon C.; Shine, Terri G.; Harlow, Peter. "Mating and Male Combat in Australian Blacksnakes, Pseudechis porphyriacus" (PDF). Journal of Herpetology. 15 (1): 101–07. doi:10.2307/1563652.
- Cogger, Harold G. (1983) . Reptiles and Amphibians of Australia (Rev. ed.). Reed. p. 449. ISBN 0883590484.
- Johnston, Christopher I.; Ryan, Nicole M; Page, Colin B; Buckley, Nicholas A; Brown, Simon GA; O'Leary, Margaret A; Isbister, Geoffrey K (2017). "The Australian Snakebite Project, 2005–2015 (ASP-20)" (PDF). Medical Journal of Australia. 207 (3): 119–25. doi:10.5694/mja17.00094.
- Toxinology.com. "CSL Antivenom Handbook". Retrieved 2007-12-28.
- Churchman, Andrew; O’Leary, Margaret A; Buckley, Nicholas A; Page, Colin B; Tankel, Alan; Gavaghan, Chris; Holdgate, Anna; Brown, Simon G A; Isbister, Geoffrey K (2010). "Clinical effects of red-bellied black snake (Pseudechis porphyriacus) envenoming and correlation with venom concentrations: Australian Snakebite Project (ASP-11)". Medical Journal of Australia. 193 (11): 696–700.
- Heller, J.; Bosward, K.L.; Hodgson, J.L.; Cole, F.L.; Reid, S.W.; Hodgson, D.R.; Mellor, D.J. (2005). "Snake envenomation in dogs in New South Wales". Austrealian Vetinary Journal. 83 (5): 286–92. doi:10.1111/j.1751-0813.2005.tb12743.x.
- Heller, J.; Bosward, K. L.; Hodgson, D. R.; Pottie, R. (2006). "Anuric renal failure in a dog after Red‐bellied Black snake (Pseudechis porphyriacus) envenomation" (PDF). Australian veterinary journal. 84 (5): 158–62. doi:10.1111/j.1751-0813.2006.tb12769.x.
- Mirtschin, Peter. "Relative Toxicity of Australian Snakes". Archived from the original on 2007-10-28. Retrieved 2007-12-28.
- Greer, Allen E. (1997). The Biology and Evolution of Australian Snakes. Chipping Norton, New South Wales: Surrey Beatty & Sons. ISBN 9780949324689.
- Pictures of Red-bellied Black Snake's fangs
- Red-bellied Black Snake – Australian Venom Research Unit, Department of Pharmacology, the University of Melbourne