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Pakobra australská (Pseudechis australis) je jedovatý had z čeledi korálovcovitých, který žije na většině území Austrálie; je považován za nejběžnějšího hada tohoto kontinentu. Zároveň je to největší australský jedovatý had a řadí se mezi desítku největších jedovatých hadů světa. Může dosahovat délky až okolo 3 metrů a vážit více než 6 kg. Žije v různých typech prostředí od tropických lesů, přes savany a křovinaté krajiny až po pouště. Živí se především plazy (včetně jedovatých hadů), žábami, ptáky, malými savci a pavouky. Jeho uštknutí je pro člověka nebezpečné ale jen zřídka smrtelné. Mezinárodní svaz ochrany přírody hodnotí tohoto plaza jako málo dotčený druh. Nejzásadnější hrozbu pro něj představuje šíření invazní ropuchy obrovské, která je pro něj při požití toxická.[2][3][4][5][6][7]
Pakobru australskou popsal pod názvem Naja australis John Edward Gray v roce 1842. Zařadil ji tedy do rodu Naja, čili mezi kobry. Druh byl ještě v 19. století přeřazen do rodu Pseudechis (anglicky black snakes, česky „pakobra“) a dlouho byl považován za taxonomicky v zásadě „vyřešený“. Koncem 20. století nicméně přišel herpetolog Raymond Hoser, publikující mimo hlavní vědecký proud, s tím, že existuje několik dalších druhů, které dle něj patří do druhového komplexu s pakobrou australskou. Tyto druhy se nazývají obvykle pygmy mulga snakes (pakobra australská se anglicky nazývá mulga snake nebo king brown snake) a žijí v severní Austrálii a na Nové Guinei. Většina vědců tuto tezi odmítla, nicméně následné genetické zkoumání v zásadě potvrdilo platnost teorie. Toto zkoumání nicméně zatím nedoporučuje pro tuto vnitrodruhovou skupinu hadů tvořenou nejméně pěti ale spíše až deseti druhy vytvářet nomenklaturu.[5][8]
Pakobra australská je mohutný had, v průměru největší ze všech australských jedovatých druhů (přibližně stejně velký, ale při stejné velikosti těžší než taipan velký). Obvyklá délka dospělých jedinců se pohybuje okolo 200 cm, ale výjimečné exempláře mohou přesahovat i 3 metry. Největší zaznamenaný kus měřil 3,3 metry. Hmotnost 2 až 2,5 metru dlouhých pakober dosahuje 3 až 6 kg.[3][5][9] Hlava je poměrně mohutná, oproti ní jsou oči spíše menší. Šupiny mají dvoubarevný nádech. Na bocích a hřbetě má vnitřek šupin hnědou, hnědo-červenou, měděnou nebo hnědo-černou barvu, zatímco okraje jsou bílo-žluté či zeleno-žluté. Zbarvení šupin však směrem do spodní části těla světlá. Břicho je krémové či narůžovělé. Ocas je celý relativně tmavý, vrchní část hlavy též. Zbarvení se rovněž liší na základě geografického rozšíření, jižní exempláře bývají tmavší než severní.[3][9] Jedové zuby měří asi 6,5 mm.[10]
Pakobra australská je nejrozšířenější jedovatý had Austrálie. Žije na většině tohoto světadílu, kromě nejjižnějších částí a některých oblastí východu. Tasmánii rovněž neobývá. V Queenslandu jeho početnost klesá. Malé formy tohoto hada se vyskytují i na Nové Guinei, ale jejich taxonomické zařazení je stále nejisté.[2][3][9]
Pakobra australská je vysoce adaptabilní druh hada, který obývá různorodé biotopy, počínaje tropickými lesy různých typů, přes savany, křovinaté krajiny až po pouštní či naopak záplavové oblasti. Nevadí mu ani krajina silně pozměněná člověkem, například pšeničná pole. Obecně se na přítomnost lidí dobře adaptoval a bez větších problémů dokáže žít v jejich blízkosti. Jeho anglický název mulga snake znamená, že se často vyskytuje v krajině, kde je hlavním stromem mulga (Acacia aneura).[3][9] Jako svůj úkryt využívá opuštěná doupata a nory, praskliny ve skalách, dutiny pod balvany, díry v hlíně, nahromaděné dřevo atd.[3]
Bývá aktivní spíše ve dne v jižních oblastech respektive naopak spíš v noci v severních oblastech výskytu.[2]
Za potravu mu slouží široká škála malých živočichů, především ptáci, savci, obojživelníci, plazi a rozliční bezobratlí (pavouci). Napadá a požírá mnohé jedovaté hady, např. pakobry ozdobné, páskované či taipany. Loví i krajty (Aspidites ramsayi). Je o něm známo, že je imunní vůči jedu různých hadů, včetně jedinců svého vlastního druhu, což je jeden z důvodů, proč má i kanibalistické sklony. Kromě živé kořisti požírá vejce ptáků a plazů a mršiny.[2][3][9]
K rozmnožování dochází nejčastěji začátkem jara (v severních oblastech zřejmě na ročním období nezáleží). Samci se angažují v rituálních soubojích, kdy se vzájemně propleteni a s hlavou vztyčenou snaží jeden druhého přetlačit a přitisknout na zem.[11] Vítězný samec se následně spáří se samicí. Ta po 39 až 42 dnech březosti naklade vejce a dále se o snůšku nestará. Počet vajec se pohybuje od 4 do 19 (20), přičemž průměrný počet je 9. Čím je samice delší, tím větší je snůška. Mláďata se líhnou po 70 až 100 dnech. Měří asi 25 cm a jsou plně samostatná.[3][9]
Dospělí jedinci pakober australských téměř nemají přirozené nepřátele. Mladé exempláře se mohou stát kořistí jiných hadů včetně jedinců vlastního druhu a dravých ptáků.[3]
Jako parazité byly zaznamenány různé hlístice, u starších jedinců bývají na těla přichycena početná klíšťata.[3]
Hlavní hrozbou pro pakobry je invazní druh žáby jménem ropucha obrovská.[2] Ta byla do australského státu Queensland dovezena v roce 1935 a od té doby se nekontrolovaně šíří. Požití této toxiny produkující ropuchy má fatální důsledky pro mnoho druhů hadů a ještěrů. Předpokládá se, že právě tyto ropuchy stojí za výrazným úbytkem pakober z oblasti Queenslandu.[2][3] Pakobra australská zahyne téměř pokaždé, když ropuchu pozře. Při pokusech v laboratoři bylo použito 11 těchto hadů, 8 na ropuchu zaútočilo, 7 ji sežralo a 6 následně uhynulo. Podobné "skóre" vykazovala i pakobra ozdobná či krajta skvrnitá. Jediní testovaní hadi, kteří ropuchy konzumovali ve větším množství a zároveň byli vůči jejich jedu immunní, byla užovka druhu Stegonotus cucullatus a pakobra druhu Demansia vestigiata.[6]
Jed pakobry australské je v databázi více než 260 jedovatých hadů 48. nejsilnější. Je-li aplikovaný intravenózně, jeho hodnota LD50 dosahuje 0,23 mg/kg (myší váhy). To odpovídá asi 1,91 až 2,38 mg/kg LD 50 aplikovaným pod kůži. Jedové váčky obsahují 1500 miligramů jedu, což je absolutně nejvyšší hodnota mezi všemi jedovatými hady.[10] Pakobra australská tak disponuje poměrně účinným jedem, jehož má obrovskou zásobu.
Pokud pakobra zaútočí, činí tak velmi zuřivě. Snaží se zakousnout co nejvíce a vstříknout velké množství jedu. Jed obsahuje zvláště myotoxiny a cytotoxiny – rozkládá červené krvinky, narušuje buněčnou strukturu a především poškozuje svaly. Má i mírně neurotoxické účinky. Úmrtí na uštknutí jsou nicméně velmi vzácná.[3][7]
Domorodí Austrálci tento druh hada běžně konzumují, na některých místech severní Austrálie je považován za důležitý zdroj masa.[2]
Pakobra australská je jedním z mála hadů, u nichž bylo zjištěno, že útočí v noci na spící lidi bez zjevného důvodu (další je například bungar modravý).[12]
Galerie pakobra australská ve Wikimedia CommonsPakobra australská (Pseudechis australis) je jedovatý had z čeledi korálovcovitých, který žije na většině území Austrálie; je považován za nejběžnějšího hada tohoto kontinentu. Zároveň je to největší australský jedovatý had a řadí se mezi desítku největších jedovatých hadů světa. Může dosahovat délky až okolo 3 metrů a vážit více než 6 kg. Žije v různých typech prostředí od tropických lesů, přes savany a křovinaté krajiny až po pouště. Živí se především plazy (včetně jedovatých hadů), žábami, ptáky, malými savci a pavouky. Jeho uštknutí je pro člověka nebezpečné ale jen zřídka smrtelné. Mezinárodní svaz ochrany přírody hodnotí tohoto plaza jako málo dotčený druh. Nejzásadnější hrozbu pro něj představuje šíření invazní ropuchy obrovské, která je pro něj při požití toxická.
Die Mulgaschlange (Pseudechis australis), im Englischen auch King Brown (Königsbraunschlange) genannt, ist eine Schlange aus der Familie der Giftnattern (Elapidae). Ihr englischer Name führt häufig zu Missverständnissen, da die Mulgaschlange keine Braunschlange, sondern eine Schwarzotter und unter anderem mit der Rotbäuchigen Schwarzotter (P. porphyriacus) verwandt ist.
Die Mulgaschlange wird 1,8 bis 2,0, in Ausnahmefällen auch 2,7 Meter lang. Ihre Körperfarbe ist oberseits einfarbig gelb- bis rotbraun, die Unterseite ist cremefarben und kann orange gepunktet sein. Kopf und Rumpf sind nicht deutlich voneinander abgesetzt. Die Augen sind groß und haben eine runde Pupille. Die Schuppen sind ungekielt und stehen in 17 Reihen. Sie hat sechs Oberlippenschilde, 185 bis 225 Bauchschilde und 50 bis 75 Schwanzschilde.
Sie ist mit Ausnahme der östlichen Küstenregionen sowie Tasmanien in ganz Australien und auf der Melville-Insel verbreitet. Sie lebt vor allem in trockenen Gegenden.
Mulgaschlangen sind tag- und nachtaktiv, bei warmem Wetter nur nachtaktiv. Sie ernähren sich von kleinen Säugetieren, Vögeln, Echsen und anderen Schlangen, auch von Artgenossen. Von Mai bis Juli ist die Paarungszeit der Schlange. Nach etwa 45 Tagen werden die Eier gelegt, die Jungtiere schlüpfen, bei einer Bruttemperatur von 26 bis 30 °C, nach etwa 60 Tagen.
Bei Begegnungen mit Menschen flüchtet die Mulgaschlange für gewöhnlich, wehrt sich jedoch, wenn sie in die Enge getrieben wird. Die Mulgaschlange zeigt ein charakteristisches Abwehrverhalten: der Vorderkörper wird bei Bedrohung aufgerichtet, das Maul aufgerissen und der Nacken leicht gespreizt. In dieser Position wird die Bedrohung fixiert. Wirkt das Abwehrverhalten nicht, erfolgen mehrere schnelle Bisse, wobei durch unterstützende Kaubewegungen nach einem Biss größere Mengen an Gift abgegeben werden. Das Gift der Mulgaschlange wirkt antikoagulierend und neurotoxisch. Die Mulgaschlange injiziert von allen Giftschlangen Australiens die größte Giftmenge pro Biss.
Die Mulgaschlange (Pseudechis australis), im Englischen auch King Brown (Königsbraunschlange) genannt, ist eine Schlange aus der Familie der Giftnattern (Elapidae). Ihr englischer Name führt häufig zu Missverständnissen, da die Mulgaschlange keine Braunschlange, sondern eine Schwarzotter und unter anderem mit der Rotbäuchigen Schwarzotter (P. porphyriacus) verwandt ist.
The king brown snake (Pseudechis australis) is a species of highly venomous snake of the family Elapidae, native to northern, western, and Central Australia. Despite its common name, it is a member of the genus Pseudechis (black snakes) and only distantly related to true brown snakes. Its alternative common name is the mulga snake, although it lives in many habitats apart from mulga. First described by English zoologist John Edward Gray in 1842, it is a robust snake up to 3.3 m (11 ft) long. It is variable in appearance, with individuals from northern Australia having tan upper parts, while those from southern Australia are dark brown to blackish. Sometimes, it is seen in a reddish-green texture. The dorsal scales are two-toned, sometimes giving the snake a patterned appearance. Its underside is cream or white, often with orange splotches. The species is oviparous. The snake is considered to be a least-concern species according to the International Union for Conservation of Nature, though may have declined with the spread of the cane toad.
Its venom is not as potent as those of Australia's other dangerous snakes, but can still cause severe effects if delivered in large enough quantities. Its main effect is on striated muscle tissue, causing paralysis from muscle damage, and also commonly affects blood clotting (coagulopathy). Often, extensive pain and swelling occur, rarely with necrosis, at the bite site. Deaths from its bites have been recorded, with the most recent being in 1969. Its victims are treated with black snake (not brown snake) antivenom.
The species was first described by English zoologist John Edward Gray in 1842 from a specimen collected at Port Essington in the Northern Territory. Gray saw little distinction from the Egyptian cobra (Naja haje) in his single preserved specimen—excepting the variation in ocular plates—and assigned the name Naja australis.[2][3] On obtaining a second specimen from the College of Surgeons, Albert Günther of the British Museum recognised an affinity with the Australian species described as Pseudechis porphyriacus, resulting in the current combination as Pseudechis australis in the black snake genus Pseudechis.[4] Scottish-Australian naturalist William Macleay described Pseudechis darwiniensis in 1878, from a more slender specimen that he thought was distinct from P. australis.[5] Belgian-British zoologist George Albert Boulenger described P. cupreus in 1896 from a specimen collected from the Murray River, distinguishing P. darwiniensis from P. australis by the shape of the frontal scale.[6] Austrian zoologist Franz Werner described Pseudechis denisonioides from Eradu, Western Australia in 1909.[7] Australian naturalist Donald Thomson obtained a skull of a large specimen with a wide head collected from East Alligator River in Arnhem Land in 1914, naming it Pseudechis platycephalus in 1933. He distinguished it from P. australis on the basis of it having anteriorly grooved palatine and pterygoid teeth, and having blunt ridges and keels on the dorsal scales.[8]
In 1955, Australian herpetologist Roy Mackay concluded that several species previously described were synonymous with P. australis, recognising that it was a highly variable taxon. He noted that P. australis had frontal scales of variable shape, and that grooves were present on the teeth of many specimens of Pseudechis, so these features did not support separate species.[9] Australian herpetologists Richard W. Wells and C. Ross Wellington described Cannia centralis in 1985 from a 1.3 m (4 ft 3 in) specimen collected 8 km (5 mi) north of Tennant Creek in 1977, distinguishing it on the basis of a narrow head;[10] however, the distinction was not supported by other authors.[2] Two new species and a new genus have been described within this complex by Australian snake-handler Raymond Hoser—the eastern dwarf mulga snake (P. pailsei) from near Mount Isa, Queensland, Australia,[11] and the Papuan pygmy mulga snake (P. rossignolii), found in Irian Jaya.[12] Hoser later also resurrected the pygmy mulga snake (P. weigeli, originally described as Cannia weigeli by Wells and Wellington in 1987[13]). These descriptions were initially received with skepticism due to the low level of evidence provided in the original descriptions.[14]
The species was long regarded as monotypic and highly variable until German biologist Ulrich Kuch and colleagues analysed the mitochondrial DNA of specimens across its range in 2005. They recovered four distinct lineages (clades); clade I (a New Guinea lineage of smaller snakes) diverged from the rest between six and four million years ago (Late Miocene to Early Pliocene), with the other three diverging in the Pleistocene. Clade II corresponded to a lineage of large snakes found across Australia, clade III was a dwarf form from the Kimberley, and clade IV contained two dwarf forms from northwestern Queensland and the Northern Territory, each of which was likely to be a distinct species.[15] In 2017, British herpetologist Simon Maddock and colleagues published a genetic analysis using mitochondrial DNA on the genus, and confirmed clade I was P. rossignoli, clade II was P. australis, clade III is an as yet unnamed dwarf species, and clade IV is P. pailsi and P. weigeli. They also determined that P. australis was most closely related to P. butleri, the spotted mulga snake.[16]
Australian medical researcher Struan Sutherland pointed out that the name "king brown snake" is a problem, as its venom is not neutralised by brown snake antivenom, which could endanger snake bite victims; he recommended dropping the name and the old term "Darwin brown snake", and using "mulga snake", instead.[17] Further complicating the issue, the term "king brown snake" has been applied to any large brown snake. Australian snake expert Glenn Shea has also pointed out that "mulga snake" has issues in that the species lives in a wide range of habitats in addition to mulga.[18] It has also been called the "Pilbara cobra".[19] Australian zoologist Gerard Krefft called it the orange-bellied brown snake.[20] In the Kaytetye language spoken in Central Australia, it is known as atetherr-ayne-wene, "budgerigar-eater".[21] The term "king brown" refers to the great size of individuals in the north and northwest of Australia, which can exceed 3 m (10 ft) in length; it is the largest and most dangerous elapid of those regions. In Southwest Australia, where the species is up to 2 m (6 ft 7 in), it is also known as the common mulga snake, distinguishing it from the spotted mulga snake Pseudechis butleri.[22]
Australia's largest venomous snake, the king brown snake can reach 2.0 to 2.5 m (6.6 to 8.2 ft) in length with a weight of 3 to 6 kg (6.6 to 13.2 lb),[15] with males around 20% larger than females.[23] The longest confirmed individual was 3.3 m (11 ft) in length.[24] The king brown snake is robust, with a head slightly wider than the body, prominent cheeks and small eyes with red-brown irises,[24] and a dark tongue.[25] The head is demarcated from the body by a slight neck.[26] Scales on the upper-parts, flanks and tail are two toned—pale or greenish yellow at the base and various shades of tan or copper, or all shades of brown from pale to blackish towards the rear. This gives the snake a reticulated pattern. The tail is often darker, while the crown is the same colour as the body.[24] The belly is cream, white or salmon and can have orange marks.[26]
The colours of the snakes' upper parts and sides differ from area to area within their range; those from northern Australia are tan, those from deserts in Central Australia have prominent white marks on each scale, giving a patterned appearance, and those from southern parts of its range are darker,[26] even blackish.[24] In Western Australia, king brown snakes south of a line through Jurien Bay, Badgingarra, New Norcia, and Quairading are significantly darker in colour.[27]
The number and arrangement of scales on a snake's body are key elements of identification to species level.[28] The king brown snake has 17 rows of dorsal scales at mid-body, 185 to 225 ventral scales, 50 to 75 subcaudal scales (all undivided, or anterior ones undivided and posterior divided, or all divided), and a divided anal scale.[26] The temporolabial scale and last (sixth) supralabial scale (both above the snake's mouth) are fused in the eastern brown snake (Pseudonaja textilis) but separate in the king brown snake.[18]
The king brown snake can be confused with brown snakes of the genus Pseudonaja, the olive python (Liasis olivaceus), water python (Liasis fuscus), spotted mulga snake, or coastal taipan (Oxyuranus scutellatus) where they co-occur.[29]
King brown snakes occur in all states of Australia except for Victoria and Tasmania.[30] It has become rare or vanished from parts of coastal Queensland.[31] The eastern limit of its range runs from Gladstone in central Queensland, and south through Gayndah, Dalby, the Warrumbungles, southwest to Condobolin and the vicinity of Balranald and then across to Port Pirie in South Australia. The southwestern limit of its range runs from Ceduna in South Australia, west through the northern Nullarbor Plain to Kalgoorlie, Narrogin and on coastal plains north of Perth.[18]
King brown snakes are habitat generalists,[23] inhabiting woodlands, hummock grasslands, chenopod scrublands, and gibber or sandy deserts nearly devoid of vegetation.[24] Within the arid to semiarid parts of their range, however, they prefer areas of greater moisture such as watercourses.[23]
They are often observed at modified habitats such as wheat fields, rubbish piles, and vacated buildings; individuals may become trapped in mine shafts and wellbores.[22] Fieldwork near Alice Springs showed that they prefer areas with buffel grass (Cenchrus ciliaris), a common introduced weed in Central Australia, possibly because of the dense, year-round cover it provides.[32]
The king brown snake is mostly crepuscular—active at dusk,[30] and is less active during the middle of the day and between midnight and dawn, retiring to crevices in the soil, old animal burrows, or under rocks or logs. During warmer months, its activity shifts to later after dusk and into the evening.[24] Across its range, it is more active during the day in cooler climates and at night in hotter climates.[23]
The breeding season begins with males engaging in wrestling combat, each attempting to push the other over for the right to mate with a female. Mating follows—in the early Southern Hemisphere spring in southwest Western Australia, mid-spring in the Eyre Peninsula, and with the wet season in the north of the country.[24] The species is oviparous, with one unverified claim of viviparity.[23] Females produce a clutch of four to 19 eggs, averaging around 10,[33] with longer females laying larger clutches,[24] generally 39 to 45 days after mating has taken place.[34] Eggs take about 70 to 100 days to hatch.[24] The incubating temperature has been recorded as between 22 and 32 °C (72 and 90 °F).[35] The eggs average 40.1 mm (1+5⁄8 in) in length by 22.9 mm (7⁄8 in) in width and weigh 13.1 g (0.46 oz) each.[36] Baby snakes average 22.6 cm (8+7⁄8 in) in length and weigh 9.4 g (0.33 oz) on hatching.[37]
King brown snakes have been reported to live up to 25 years in captivity.[38]
The king brown snake is a generalist predator, preying on frogs, lizards including small monitors, skinks, geckos and agamids, other snakes including whip snakes, brown snakes, the brown tree snake (Boiga irregularis), southern shovel-nosed snake (Brachyurophis semifasciatus), Gould's hooded snake (Parasuta gouldii) and crowned snake (Elapognathus coronatus), birds such as thornbills, and small mammals such as rodents and dasyurids.[23] and spiders such as the infamous funnel web spiders, mouse spiders and tarantulas. The species has been reported eating roadkill, as well as the sloughed skins of other reptiles, and is known to exhibit cannibalism. Specimens in captivity have been observed eating their own faeces.[22] It is opportunistic, eating a higher proportion of frogs in wetter areas.[23]
King brown snakes are sensitive to cane toad toxins and have died after eating them.[39] Despite this, field research before and after the arrival of cane toads to the Adelaide River floodplain in the Northern Territory did not show a decline in king brown snake numbers, though this could have been coincidental; the population of this species had already declined in the region.[40]
The king brown snake accounted for 4% of identified snakebite attacks in Australia between 2005 and 2015, with no deaths recorded.[41] The last recorded death occurred in 1969,[42] when a 20-year-old man was bitten while reaching around for a packet of cigarettes under his bed in Three Springs, Western Australia. The man was treated over two days, with twice daily injections of death adder, brown snake and tiger snake antivenin, yet died in 37 hours despite this medical attention. This incident led to the introduction of Papuan black snake antivenom for treatment of king brown snake envenomation.[43] Before this it had been confirmed in one fatality and suspected in another in the early 1960s.[44] Venomous snakes normally only bite humans when disturbed. King brown snakes have been noted, however, to bite people who were asleep at the time.[42][45] Furthermore, a significant number of victims have been snake handlers. These have resulted in a high proportion of bites occurring on upper limbs.[42] The king brown snake is classified as a snake of medical importance by the World Health Organization.[46][a]
The king brown snake can bite repeatedly and chew to envenomate a victim.[47] Considerable pain, swelling, and tissue damage often occur at the site of a king brown snake bite.[42] Local necrosis has been recorded.[48] In 1998, a person bitten 9–12 times on his arm required an amputation of the envenomed limb.[42] He reported later that he had impulsively decided to commit suicide by placing his hand in a bag with a king brown snake inside and stirring it up.[49] A large king brown snake delivers on average 180 mg of venom in one bite. A 2.5 m (8 ft 2 in) long king brown snake milked by snake handler John Cann produced 1350 mg, and then 580, 920, and 780 mg at three, four, and five months after the first milking.[47] This record was broken in 2016, when a king brown snake called "chewi"—also 2.5 m (8 ft 2 in) long—produced 1500 mg of venom at the Australian Reptile Park.[50] The volume of venom produced in laboratories is equivalent to the amounts produced by the king cobra (Ophiophagus hannah) and gaboon adder (Bitis gabonica).[22] In a laboratory experiment on mice, not only did the king brown snake inject far more venom than other species of dangerous snake, very little of its venom (0.07 mg of 62 mg) was left on the skin.[51] When using 0.1% bovine serum albumin in saline rather than saline alone, the venom has a murine median lethal dose (LD50) of 1.91 mg/kg (0.866 mg/lb) when administered subcutaneously.[52]
The main toxic agents of king brown snake venom are myotoxins hazardous to striated muscles and kidney cells.[30] Toxic effects are proportional to the amount of venom in the victim. Nonspecific symptoms of poisoning are common and include nausea and vomiting, abdominal pain, diarrhea, generalized sweating (diaphoresis), and headache. Impaired clotting (coagulopathy) is common, and can be diagnosed with an elevated activated partial thromboplastin time (aPTT). Symptoms of myotoxicity (muscle damage) include muscle pain and weakness in the presence of an elevated creatine kinase (CK). King brown snake venom has some haemolytic activity, and some patients get a short-term fall in red blood cells.[48]
A major component of king brown snake venom are phospholipase A2 enzymes, which have diverse effects that are commonly found in snake venoms.[47] These proteins are directly toxic on muscle tissue due to their sheer volume in the venom, and are destructive to cell membranes and liberate lysophospholipids (involved in cell lysis) and arachidonate (a precursor in inflammatory response). Despite containing a number of agents with phospholipase A2 activity, king brown snake venom exhibits little neurotoxicity.[53]
The venom has multiple proteins with antibiotic activity, including two L-amino-acid oxidases (LAO1 and LAO2) that exhibit activity against the pathogenic bacterium Aeromonas hydrophila, which is commonly present in frogs. Also present are three protein isoforms of transferrin; transferrin binds serum iron (Fe3+), which makes the environment less hospitable for bacteria and hence has an antibiotic effect.[53] Pseudechetoxin and pseudecin are two proteins that block cyclic nucleotide–gated ion channels, including those present in retinal photoreceptors and olfactory receptor neurons.[54]
Standard first-aid treatment for any suspected bite from a venomous snake uses a pressure bandage to the bite site. The victims should move as little as possible and be conveyed to a hospital or clinic, where they should be monitored for at least 24 hours. The tetanus vaccine is given, though the mainstay of treatment is the administration of the appropriate antivenom.[55] Black-snake antivenom is used to treat bites from this species. Christopher Johnston and colleagues propose giving antivenom immediately if king brown snake envenoming is suspected, as a delay of more than two hours did not prevent muscle damage in a review of treated snakebite victims. They add that it is reasonable to assume that if a snakebite victim had a raised aPTT and signs of haemolysis, then a king brown snake is the culprit.[48] Shahab Razavi and colleagues add that more than one vial of antivenom might be needed if envenoming is severe.[42]
King brown snakes are readily available in Australia via breeding in captivity. They are regarded as straightforward to keep, due to the low likelihood of biting and relatively low toxicity of their venom,[38] though the potentially large amount injected makes it more hazardous.[47]
The king brown snake is considered to be a least-concern species according to the International Union for Conservation of Nature.[1] Small snakes may be eaten by birds of prey. In contrast, old snakes are frequently infested with ticks.[24]
Mutitjulu Waterhole at Uluru marks the site between two Central Australian ancestral beings Kuniya (woma python woman) and Liru (king brown snake man). Here, Kuniya avenged the death of her nephew, who was fatally speared by Liru, by striking him with her digging stick.[56]
Among the Djambarrpuyngu clan of the Yolngu people in northeastern Arnhem Land, King Brown Snake is the Ngurruyurrtjurr ancestor, and its homeland is Flinders Point in Arnhem Land.[57]
Known as darrpa to indigenous people of East Arnhem land, the king brown snake was historically responsible for deaths there. Folk treatment involved capturing the snake and watching it bleed, which would supposedly make the victim recover. If the snake were killed, its victim would die also. Another folk remedy involved blowing smoke through a hollow branch or pandanus leaf onto the victim sitting by a campfire. If the smoke resembled the mali, or immaterial form, of a snake, then the person would die, as the victim of a ragalk (sorcerer).[58]
In Kunwinjku country in West Arnhem Land, the king brown snake is known as dadbe.[59] The Kurulk clan would not collect white paint from a site in the wet season, as they believed it was the snake's faeces, and they were afraid of its anger.[60]
Kurrmurnnyini is a lagoon and complex of sandstone outcrops near Borroloola in the southwestern Gulf Country in the Northern Territory. Here the King Brown Snake Ancestral Being—balngarrangarra in Gudanji and ngulwa in Yanyuwa—was sleeping about 1.5 km (0.93 mi) north of the lagoon when it was disturbed by ngabaya—ancestral spirit men. Angrily, he bit the rocks, which became tainted and poisonous, and an instrument of narnu‐bulabula (sorcery). Local sorcerers would cast a spell by inserting a potential victim's item of clothing in a hole in the rock or sharpening a stick and calling out their name while inserting it in the rock face. The victim would then perish. Only men descended from King Brown Snake Ancestor could be sorcerers, though others might hire them. Local people feared and avoided the location.[61]
The title character picks up a king brown snake in the 1986 film Crocodile Dundee.[62]
The king brown snake (Pseudechis australis) is a species of highly venomous snake of the family Elapidae, native to northern, western, and Central Australia. Despite its common name, it is a member of the genus Pseudechis (black snakes) and only distantly related to true brown snakes. Its alternative common name is the mulga snake, although it lives in many habitats apart from mulga. First described by English zoologist John Edward Gray in 1842, it is a robust snake up to 3.3 m (11 ft) long. It is variable in appearance, with individuals from northern Australia having tan upper parts, while those from southern Australia are dark brown to blackish. Sometimes, it is seen in a reddish-green texture. The dorsal scales are two-toned, sometimes giving the snake a patterned appearance. Its underside is cream or white, often with orange splotches. The species is oviparous. The snake is considered to be a least-concern species according to the International Union for Conservation of Nature, though may have declined with the spread of the cane toad.
Its venom is not as potent as those of Australia's other dangerous snakes, but can still cause severe effects if delivered in large enough quantities. Its main effect is on striated muscle tissue, causing paralysis from muscle damage, and also commonly affects blood clotting (coagulopathy). Often, extensive pain and swelling occur, rarely with necrosis, at the bite site. Deaths from its bites have been recorded, with the most recent being in 1969. Its victims are treated with black snake (not brown snake) antivenom.
La serpiente de Mulga (Pseudechis australis) es un ofidio de la Australia continental que pertenece al género Pseudechis o serpientes negras.[3][4] Alcanza en torno a los 2,7 m de longitud y es una de las serpientes más largas de Australia.[5]
Debido a la introducción del sapo de caña o sapo marino, Rhinella marina, en 1935 en Australia, esta especie de serpiente se ha visto enormemente amenazada (llegando a reducir el número de individuos en un 90%) y en peligro de extinción.[6]
A pesar de no ser agresiva, la serpiente mulga es la responsable del 4% de todas las mordeduras en Australia.
Los síntomas más comunes después de una mordedura son: mareo, vómito, dolor abdominal, dolor de cabeza, hinchazón y necrosis alrededor de la zona afectada. Sin embargo, la posibilidad de morir a manos de esta serpiente es muy baja, aunque se puede perder la extremidad, debido a la necrosis.[7]
La serpiente de Mulga (Pseudechis australis) es un ofidio de la Australia continental que pertenece al género Pseudechis o serpientes negras. Alcanza en torno a los 2,7 m de longitud y es una de las serpientes más largas de Australia.
Debido a la introducción del sapo de caña o sapo marino, Rhinella marina, en 1935 en Australia, esta especie de serpiente se ha visto enormemente amenazada (llegando a reducir el número de individuos en un 90%) y en peligro de extinción.
Pseudechis australis Pseudechis generoko animalia da. Narrastien barruko Elapidae familian sailkatuta dago.
Pseudechis australis Pseudechis generoko animalia da. Narrastien barruko Elapidae familian sailkatuta dago.
Pseudechis australis, le Serpent de la Mulga, est une espèce de serpents de la famille des Elapidae[1].
Cette espèce est endémique d'Australie.
C'est un serpent commun en Australie où on le trouve partout sauf en Tasmanie et au Victoria.
C'est par sa taille le deuxième plus grand serpent venimeux australien après le taïpan, il mesure de deux-et-demi à trois mètres de long et sa couleur varie suivant les régions: brun clair dans les régions désertiques, brun foncé dans les régions plus froides du Queensland, de l'Australie-Méridionale et de la Nouvelle-Galles du Sud.
Il se nourrit d'autres reptiles, y compris d'autres serpents venimeux, d'oiseaux, de mammifères ou de grenouilles.
Ce serpent venimeux produit de grandes quantités de venin.
Pseudechis australis, le Serpent de la Mulga, est une espèce de serpents de la famille des Elapidae.
Mulga atau yang juga disebut Ular cokelat raja (Ingg: King Brown) atau Ular sendok Pilbara (Pilbara Cobra) adalah jenis tedung senawan yang berbisa kuat dari Australia. Ular ini adalah ular berbisa terpanjang kedua di Australia setelah Taipan pesisir.
Panjang ular ini dapat mencapai 3 meter. Warna tubuh ular ini bervariasi tergantung habitat yang dihuninya. Untuk yang tinggal di hutan atau semak-semak, warnanya cenderung cokelat gelap. Sedangkan yag hidup di sabana/stepa atau gurun, warnanya cenderung lebih cerah.[2][3]
Karena warna tubuhnyalah yang membuat orang sering menyangka ular ini adalah ular cokelat. Sehingga banyak kasus orang yang baru digigit ular ini mendapat antibisa yang salah, kemudian orang yang digigit akhirnya meninggal, meskipun pada beberapa kasus korbannya masih hidup.[4]
Ular ini menghuni hampir semua tipe habitat dan lingkungan. Mulai dari hutan hujan, semak, dekat perairan, batang pohon yang tumbang, di bawah batu, padang rumput (sabana), gurun, bahkan di kawasan pertanian dan pemukiman dan sering didapati di bawah tumpukan kayu, lempengan besi, sampah, jerami; dimanapun ia dapat menemukan mangsanya yang terdiri dari tikus, anak unggas, burung, kadal, dan katak, bahkan ular jenis lain yang lebih kecil ukurannya, baik yang tidak berbisa maupun berbisa. Hal-hal itulah yang membuat ular ini sangat dikenal oleh hampir semua herpetolog dunia karena sifatnya yang multi-habitat dan omni-karnivora.[2]
Ular ini tersebar luas di seluruh Australia. Namun ular ini tidak terdapat di wilayah paling barat-daya, sepanjang pesisir selatan, negara bagian Victoria, dan Tasmania.[5]
Mulga atau yang juga disebut Ular cokelat raja (Ingg: King Brown) atau Ular sendok Pilbara (Pilbara Cobra) adalah jenis tedung senawan yang berbisa kuat dari Australia. Ular ini adalah ular berbisa terpanjang kedua di Australia setelah Taipan pesisir.
Il serpente bruno reale (Pseudechis australis) è un serpente velenoso. Chiamato dagli australiani King Brown per via della colorazione e delle dimensioni, è il serpente velenoso più diffuso in Australia.[1]
Di dimensioni che variano tra gli 1.5 e i 3 metri circa, è un serpente piuttosto grande dal corpo cilindrico di colore solitamente marrone uniforme ( da qui l'aggettivo in lingua inglese brown ) sul dorso, che va gradatamente schiarendosi sul ventre. La colorazione di questa specie può variare in base alla distribuzione geografica, e può raggiungere tonalità vicine al grigio, al nero e al rosso. È attivo sia durante le ore notturne quanto in quelle diurne . Nei mesi estivi cerca riparo in grotte o fessure tra le rocce durante le ore più calde della giornata, per cacciare le sue prede al crepuscolo. Il King Brown è un agile e polivalente predatore che si nutre di sauri, anfibi, roditori e occasionalmente di uccelli; inoltre è ben adattato a predare altri serpenti, inclusi quelli velenosi.
La sua distribuzione è molto ampia, dall'estremo sud della Nuova Guinea a tutta l'Australia (esclusa la costa meridionale) e si può dire altrettanto della sua diffusione: sono molteplici gli habitat in cui lo si può trovare, dalle foreste al deserto, spesso addirittura in prossimità dei grandi centri abitati. Questa sua grande adattabilità ad ambienti diversi, la sua ampia diffusione unita ad un potente veleno (LD50 di 1.94 mg/kg), lo rendono uno tra i serpenti più pericolosi dell'Australia, probabilmente secondo solo al taipan. Di norma non ha un temperamento aggressivo, ma, se minacciato o impossibilitato alla fuga, rivela un temperamento assai battagliero: appiattendo il collo a forma di nastro, emette forti sibili e solleva il corpo fino a un terzo della sua lunghezza, preparandosi a colpire l'aggressore.
Nonostante abbia un veleno dal minore tasso di velenosità rispetto al taipan, è tuttavia in grado di inocularne quantità elevatissime con un solo morso (fino a 4 - 5 volte di più rispetto alla media); in aggiunta, spesso morde più volte o tende a "masticare" l'obbiettivo. Tutti motivi in più per trattare questo serpente con estrema cautela.
La stagione degli amori e l'accoppiamento occorrono solitamente nella tarda primavera. Depone in media dalle 11 alle 16 uova, ma secondo occasione può essere anche ovoviviparo, partorendo da 16 a 22 neonati.
Il serpente bruno reale (Pseudechis australis) è un serpente velenoso. Chiamato dagli australiani King Brown per via della colorazione e delle dimensioni, è il serpente velenoso più diffuso in Australia.
Mulga (Pseudechis australis)[3] – gatunek węża z rodziny zdradnicowatych (Elapidae). Jeden z najdłuższych węży jadowitych świata i drugi po tajpanie nadbrzeżnym najdłuższy wąż jadowity występujący w Australii.
Mulgi zwykle osiągają od 2,5 m do 3 m długości. Charakteryzują się krępą budową ciała i szeroką głową. W zależności od miejsca występowania ich skóra może być jasnobrązowa z miedzianym odcieniem w rejonach pustynnych do ciemnobrązowej lub czarnej w chłodniejszych regionach Queensland, Australii Południowej i Nowej Południowej Walii.
Siedliskiem mulg są łąki, wrzosowiska, pustynie i otwarte lasy.
Polują głównie na inne małe gady: jaszczurki i węże, oraz niektóre ptaki, ssaki i żaby.
Samica składa od 8 do 20 jaj w opuszczonej norze, pod zwalonym drzewem lub pod kamieniem. Inkubacja trwa od 2 do 3 miesięcy. Młode po wykluciu mogą liczyć tylko na siebie.
Występuje w całej Australii z wyjątkiem wschodnich i południowych obszarów przybrzeżnych.
Mulga (Pseudechis australis) – gatunek węża z rodziny zdradnicowatych (Elapidae). Jeden z najdłuższych węży jadowitych świata i drugi po tajpanie nadbrzeżnym najdłuższy wąż jadowity występujący w Australii.
Mulgi zwykle osiągają od 2,5 m do 3 m długości. Charakteryzują się krępą budową ciała i szeroką głową. W zależności od miejsca występowania ich skóra może być jasnobrązowa z miedzianym odcieniem w rejonach pustynnych do ciemnobrązowej lub czarnej w chłodniejszych regionach Queensland, Australii Południowej i Nowej Południowej Walii.
Siedliskiem mulg są łąki, wrzosowiska, pustynie i otwarte lasy.
Polują głównie na inne małe gady: jaszczurki i węże, oraz niektóre ptaki, ssaki i żaby.
Samica składa od 8 do 20 jaj w opuszczonej norze, pod zwalonym drzewem lub pod kamieniem. Inkubacja trwa od 2 do 3 miesięcy. Młode po wykluciu mogą liczyć tylko na siebie.
Występuje w całej Australii z wyjątkiem wschodnich i południowych obszarów przybrzeżnych.
Pseudechis australis là một loài rắn trong họ Rắn hổ. Loài này được Gray mô tả khoa học đầu tiên năm 1842.[2] Đây là một loài rắn có nọc độc được tìm thấy ở Úc. Đây là một trong những loài rắn có nọc độc dài nhất thế giới và là loài dài thứ hai ở Úc (chỉ vượt qua loài taipan ven biển). Tên phổ biến thay thế của nó là rắn nâu vua, mặc dù nó là một loài trong chi Pseudechis (rắn đen) và chỉ liên quan xa đến rắn nâu thực sự.
Rắn Mulga là loài rắn lớn, có nọc độc dài tới 2,5 đến 3,0 m trong các mẫu vật lớn nhất, mặc dù 1,5 m (4,9 ft) là chiều dài điển hình hơn đối với một người trưởng thành trung bình. Chúng vượt quá chiều dài giữa những con rắn có nọc độc chỉ thua rắn hổ mang chúa về chiều dài, một số loài mambas châu Phi, chi Lachesis (người đi rừng) thuộc hệ thần kinh Mỹ và taipan Úc. Một con rắn mulga trưởng thành có kích thước tốt, dài từ 2,0 đến 2,5 m (6,6 đến 8,2 ft) có thể nặng từ 3 đến 6 kg (6,6 đến 13,2 lb) và rắn mulga thường nặng hơn so với taipans xảy ra. Màu sắc của loài rắn này khác nhau từ khu vực này đến khu vực khác trong phạm vi của chúng; chúng có thể là một màu nâu nhạt trên sa mạc đến một màu tối, nâu đen ở các khu vực mát mẻ của Queensland, Nam Úc và New South Wales. Loài rắn này mạnh mẽ, với cái đầu rộng và mõm mịn. Số lượng và cách sắp xếp các vảy trên cơ thể rắn là yếu tố chính để nhận dạng cấp loài.
Rắn Mulga chiếm 4% số nạn nhân bị rắn cắn được xác định ở Úc từ năm 2005 đến 2015, không có trường hợp tử vong nào được ghi nhận. Nọc độc của Mulga bao gồm các độc tố. Nọc độc có liều gây chết trung bình ở chuột (LD50) đã được đo ở mức 1,91 mg / kg (khi sử dụng albumin huyết thanh 0,1% trong nước muối thay vì chỉ dùng nước muối) khi tiêm dưới da. Nọc độc của nó không đặc biệt độc hại với chuột, nhưng nó được sản xuất với số lượng rất lớn: một con rắn mulga lớn có thể cung cấp 150 mg trong một vết cắn, trong khi so sánh, rắn hổ trung bình chỉ tạo ra 10-40 mg khi được vắt nọc độc. Antivenin rắn đen được sử dụng để điều trị vết cắn từ loài này, sau khi bộ phát hiện nọc độc CSL đã trả lại kết quả cuối cùng cho việc tiêm men mulga, và các dấu hiệu cho thấy việc sử dụng antivenin là bắt buộc. Rắn độc thường chỉ tấn công con người khi bị quấy rầy. Tuy nhiên, rắn Mulga đã được ghi nhận để cắn những người đang ngủ lúc đó.
Pseudechis australis là một loài rắn trong họ Rắn hổ. Loài này được Gray mô tả khoa học đầu tiên năm 1842. Đây là một loài rắn có nọc độc được tìm thấy ở Úc. Đây là một trong những loài rắn có nọc độc dài nhất thế giới và là loài dài thứ hai ở Úc (chỉ vượt qua loài taipan ven biển). Tên phổ biến thay thế của nó là rắn nâu vua, mặc dù nó là một loài trong chi Pseudechis (rắn đen) và chỉ liên quan xa đến rắn nâu thực sự.
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