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46-494: Mambas are fast-moving, highly venomous snakes of the genus Dendroaspis (which literally means "tree asp ") in the family Elapidae . Four extant species are recognised currently; three of those four species are essentially arboreal and green in colour, whereas the black mamba , Dendroaspis polylepis , is largely terrestrial and generally brown or grey in colour. All are native to various regions in sub-Saharan Africa and all are feared throughout their ranges, especially

92-494: A Czech zoo gave birth to 156 young, the largest litter for any species of snake. These snakes do well in captivity, but gluttony has been reported. Kauffeld (1969) mentions that specimens can be maintained for years on only one meal per week, but that when offered all they can eat, the result is often death, or at best wholesale regurgitation. They are bad-tempered snakes, and some specimens never settle down in captivity, always hissing and puffing when approached. This species

138-466: A cobra , the threat display of a mamba includes rearing, opening the mouth and hissing. The black mamba's mouth is black within, which renders the threat more conspicuous. A rearing mamba has a narrower yet longer hood and tends to lean well forward, instead of standing erect as a cobra does. Stories of black mambas that chase and attack humans are common, but in fact the snakes generally avoid contact with humans. The black mamba ( Dendroaspis polylepis )

184-420: A less than triangular shape with a blunt and rounded snout. Still, the head is much wider than the neck. The rostral scale is small. The circumorbital ring consists of 10–16 scales. Across the top of the head, there are 7–11 interocular scales ; three or four scales separate the suboculars and the supralabials . It has 12 to 17 supralabials and 13–17 sublabials . The first three or four sublabials contact

230-480: A pheromone to attract males, which engage in neck-wrestling combat dances. A female in Malindi was followed by seven males. They give birth to large numbers of offspring; litters over 80 have been reported, while 50–60 are not unusual. Newborns are 12.5–17.5 cm (4.9–6.9 in) in length. Very large specimens, particularly those from East Africa, give birth to the highest numbers of offspring. A Kenyan female in

276-425: A strike, the force of the impact is so strong, and the long fangs penetrate so deeply, that prey items are often killed by the physical trauma alone. The fangs apparently can penetrate soft leather. They can strike to a distance of about one-third of their body length, but juveniles can launch their entire bodies forwards in the process. These snakes rarely grip their victims, but instead release quickly to return to

322-430: A truly intramuscular bite, snakebites rarely cause IV envenomation , and IP envenomation is even rarer. Measurements of LD 50 using dry venom mixed with 0.1% bovine serum albumin in saline are more consistent than the results obtained using saline alone. As an example, the venom of the eastern brown snake has a murine LD 50 (SC) of 41 μg/kg when measured in 0.1% bovine serum albumin in saline; when saline alone

368-451: Is venomous . Two subspecies are currently recognized, including the nominate subspecies described here. The species is commonly known as the puff adder , African puff adder , or common puff adder . German naturalist Blasius Merrem described the puff adder in 1820. The word arietans means "striking violently" and is derived from the Latin arieto . The type locality given

414-610: Is " Promontorio bonae spei " ( Cape of Good Hope ), South Africa . The snake's typical size is about 1.0 m (39.3 in) in total length (body and tail) and very stout. Large specimens of 190 cm (75 in) total length, weighing over 6.0 kg (13.2 lb) and with a girth of 40 cm (16 in) have been reported. Specimens from Saudi Arabia are not as large, usually no more than 80 cm (31 in) in total length. Males are usually larger than females and have relatively longer tails. The color pattern varies geographically. The head has two well-marked dark bands – one on

460-518: Is 0.24 mg/kg and 0.155 mg/kg. Studies on mice and human cardiac cell culture show that venom of the inland taipan is the most toxic among all snakes. The toxicity of snake venom, based on laboratory tests conducted on mice, is sometimes used to gauge the extent of danger to humans, but this is not enough. Many venomous snakes are specialized predators whose venom may be adapted specifically to incapacitate their preferred prey. A number of other factors are also critical in determining

506-520: Is a highly venomous viper species found in savannahs and grasslands from Morocco and western Arabia throughout Africa except for the Sahara and rainforest regions. It is responsible for causing the most snakebite fatalities in Africa owing to various factors, such as its wide distribution, frequent occurrence in highly populated regions, and aggressive disposition. Like all other vipers, it

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552-482: Is a highly venomous snake species native to various parts of sub-Saharan Africa. Black mambas are fast-moving, nervous snakes that will strike when threatened. According to findings by Branch (2016), their venom comprises neurotoxins and cardiotoxins that can rapidly induce symptoms, including dizziness, extreme fatigue, vision problems, foaming at the mouth, paralysis, convulsions, and eventual death from respiratory or cardiac failure if untreated. Although black mamba venom

598-621: Is found in most African regions and on parts of the Arabian Peninsula . It is found in all habitats except true deserts, rainforests, and (tropical) alpine habitats. It is most often associated with rocky grasslands. It is not found in rainforest areas, such as along the coast of West Africa and in Central Africa (i.e., central DR Congo); it is also absent from the Mediterranean coastal region of North Africa . On

644-573: Is highly toxic, antivenom is available and can treat envenomation promptly. Most apparent cases of pursuit probably are examples of where witnesses have mistaken the snake's attempt to retreat to its lair when a human happens to be in the way. The black mamba usually uses its speed to escape from threats, and humans actually are their main predators, rather than prey. All mambas have medically significant venom , with dendrotoxins , short chain alpha-neurotoxins , cardiotoxins and fasciculins . All mambas are classified as snakes of medical importance by

690-653: Is modified saliva used for prey immobilization and self-defense and is usually delivered through highly specialized teeth, hollow fangs, directly into the bloodstream or tissue of the target. Evidence has recently been presented for the Toxicofera hypothesis, that venom was present (in small amounts) in the ancestors of all snakes (as well as several lizard families) as "toxic saliva" and evolved to extremes in those snake families normally classified as venomous by parallel evolution . The Toxicofera hypothesis further implies that "nonvenomous" snake lineages have either lost

736-571: Is probably based on a single medical record made in a single district between 1957 and 1963 when specific antivenom had yet to be introduced. Seven out of seven victims of this species who received non-specific polyvalent antivenom , that had no effect on the species' toxins, succumbed to its bites. However, another snakebite survey in South Africa reported a death rate of approximately 43% among those who received ineffective treatments (15 fatal cases out of 35 patients). A mamba-specific antivenom

782-650: Is responsible for more snakebite fatalities than any other African snake, due to a combination of factors, including its wide distribution, common occurrence, large size, potent venom that is produced in large amounts, long fangs, and their habit of basking by footpaths and sitting quietly when approached. The venom has cytotoxic effects and is one of the most toxic of any vipers based on LD 50 . The LD 50 values in mice vary: 0.4–2.0 mg/kg intravenously , 0.9–3.7 mg/kg peritoneally , and 4.4–7.7 mg/kg subcutaneously (SC). Mallow et al. (2003) give an LD 50 range of 1.0–7.75 mg/kg SC. Venom yield

828-617: Is typically 150–350 mg, with a maximum of 750 mg. Brown (1973) mentions a venom yield of 180–750 mg. About 100 mg (1.5 gr) are thought to be enough to kill a healthy adult human male, with death occurring after 25 hours. In humans, bites from this species can produce severe local and systemic symptoms. Based on the degree and type of local effect, bites can be divided into two symptomatic categories – those with little or no surface extravasation , and those with hemorrhages evident as ecchymosis , bleeding, and swelling. In both cases, severe pain and tenderness occur, but in

874-579: Is understood to mean "shield", but also denotes "cobra" or simply "snake", in particular "snake with hood (shield)". Via Latin aspis , it is the source of the English word "asp". In ancient texts, aspis or asp often referred to the Egyptian cobra ( Naja haje ), in reference to its shield-like hood. The genus was first described by the German naturalist Hermann Schlegel in 1848, with Elaps jamesonii as

920-519: Is used, the value is 53 μg/kg . Belcher's sea snake , which sometimes is mistakenly called the hook-nosed sea snake , has been erroneously popularized as the most venomous snake in the world, due to the first edition of Ernst and Zug's book, Snakes in Question: The Smithsonian Answer Book , published in 1996. Prominent venom expert Associate Professor Bryan Grieg Fry has clarified the error: "The hook nosed myth

966-503: The Western Cape province of South Africa, that usually have a striking yellow-and-black color pattern. Puff adders have a form of olfactory crypsis which has been shown to make detecting them difficult for trained dogs and meerkats, both scent-based predators. The exact nature of this ability is not known, but is hypothesized to be related to a low metabolic rate, as well as relocation after shedding and defecating. The head has

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1012-539: The World Health Organization . There are multiple components in dendrotoxins with different targets: Toxicity alone does not determine severity of envenomation ; other factors include the snake's temperament, venom yields, proximity of wounds to the CNS and depth of punctures. Bites by all members of this genus are capable of causing rapid onsets of symptoms, but it is the black mamba whose bite has

1058-432: The puff adder . Besides proximity to residences, behaviour of a given species is also a critical aspect when it comes to snakebite morbidities. Mambas are agile, usually fleeing from any confrontation with unambiguous threat display which allows early recognition of the serpent, avoiding escalation in tension. Dendroaspis , is derived from Ancient Greek déndron ( δένδρον ), meaning "tree", and aspis ( ασπίς ), which

1104-415: The type species . It was misspelt as Dendraspis by Dumeril in 1856, and generally uncorrected by subsequent authors. In 1936, Dutch herpetologist Leo Brongersma pointed out that the correct spelling was Dendroaspis but added that the name was invalid as Fitzinger had coined Dendraspis in 1843 for the king cobra and hence had priority. However, in 1962 German herpetologist Robert Mertens proposed that

1150-466: The 1843 description of Dendraspis by Fitzinger be suppressed due to its similarity to Dendroaspis , and the confusion it would cause by its use. Black mambas live in the savannas and rocky hills of southern and eastern Africa. They are Africa's longest venomous snake, reaching up to 14 feet in length, although 8.2 feet is more the average. They are also among the fastest snakes in the world, slithering at speeds of up to 12.5 miles per hour. * Including

1196-711: The Arabian Peninsula, it is found as far north as Ta'if . It has been reported to be found in the Dhofar region of southern Oman . Normally a sluggish species, the puff adder relies on camouflage for protection. Locomotion is primarily rectilinear , using the broad ventral scales in a caterpillar fashion and aided by its own weight for traction. When agitated, it can resort to a typical serpentine movement of surprising speed. Although mainly terrestrial, these snakes are good swimmers and can also climb with ease; often they are found basking in low bushes. One specimen

1242-409: The ability to produce venom (but may still have lingering venom pseudogenes ), or actually do produce venom in small quantities, likely sufficient to help capture small prey but causing no harm to humans when bitten. There is not a single or special taxonomic group for venomous snakes. Venom is known in several families. This has been interpreted to mean venom in snakes originated more than once as

1288-471: The back and tail. Usually, these bands are roughly chevron-shaped, but may be more U-shaped in some areas. They also form two to six light-and-dark cross-bands on the tail. Some populations are heavily flecked with brown and black, often obscuring other coloration, giving the animal a dusty-brown or blackish appearance. The belly is yellow or white, with a few scattered dark spots. Newborn young have golden head markings with pinkish to reddish ventral plates toward

1334-417: The black mamba. In Africa there are many legends and stories about mambas. The three green species of mambas are arboreal , whereas the black mamba is largely terrestrial. All four species are active diurnal hunters, preying on birds , lizards , and small mammals . At nightfall some species, especially the terrestrial black mamba, shelter in a lair. A mamba may retain the same lair for years. Resembling

1380-456: The bone. Gangrene and secondary infections commonly occur and can result in loss of digits and limbs. The fatality rate highly depends on the severity of the bites and some other factors. Deaths can be exceptional and probably occur in less than 15% of all untreated cases (usually in 2–4 days from complications following blood volume deficit and disseminated intravascular coagulation ), although some reports show that severe envenomations have

1426-446: The chin shields, of which only one pair exists. Often, two fangs are on each maxilla , and both can be functional. Midbody, the snake has 29–41 rows of dorsal scales . These are strongly keeled except for the outermost rows. The ventral scale count is 123–147, the subcaudals number 14–38. Females have no more than 24 subcaudals. The anal scale is single. This species may be the most common and widespread snake in Africa. It

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1472-448: The crown and the other between the eyes. On the sides of the head, two oblique, dark bands or bars run from the eye to the supralabials. Below, the head is yellowish white with scattered dark blotches. Iris color ranges from gold to silver-gray. Dorsally, the ground color varies from straw yellow, to light brown, to orange or reddish brown. This is overlaid with a pattern of 18–22 backwardly directed, dark brown to black bands that extend down

1518-478: The four delivery sites is used for the injection: subcutis (SC), vein (IV), muscle or peritoneum (IP). Smaller murine LD 50 values indicate venoms that are more toxic, and there have been numerous studies on snake venom with a variability of potency estimates. SC LD 50 is considered the most applicable to actual bites as only vipers with large fangs (such as large specimens from the genera Bitis , Bothrops , Crotalus , or Daboia ) are capable of

1564-451: The inland taipan, are found in closer proximity to human settlements and are more confrontational, thus leading to more deaths from snakebite. In addition, some species, such as the black mamba and coastal taipan , occasionally show some aggression, generally when alarmed or in self-defence, and then may deliver fatal doses of venom, resulting in high human mortality rates. Puff adder#Venom The puff adder ( Bitis arietans )

1610-463: The lateral edges. One unusual specimen, described by Branch and Farrell (1988), from Summer Pride, East London , in South Africa, was striped. The pattern consisted of a narrow (one scale wide), pale yellowish stripe that ran from the crown of the head to the tip of the tail. Generally, though, these are relatively dull-looking snakes, except for male specimens from highland East Africa and

1656-433: The latter, widespread superficial or deep necrosis and compartment syndrome are seen. Serious bites cause limbs to become immovably flexed as a result of significant hemorrhage or coagulation in the affected muscles. Residual induration, however, is rare and usually these areas completely resolve. Other bite symptoms that may occur in humans include edema , which may become extensive, shock, watery blood oozing from

1702-480: The nominate subspecies. Type species . A 2018 analysis of the venom of the mambas, as well as a 2016 genetic analysis, found the following cladogram representative of the relationship between the species. Ophiophagus hannah D. j. jamesoni D. j. kaimosae D. viridis D. angusticeps D. polylepis Venomous snake The evolutionary history of venomous snakes can be traced back to as far as 28 million years ago. Snake venom

1748-444: The potential hazard of any given venomous snake to humans, including their distribution and behavior. For example, while the inland taipan is regarded as the world's most venomous snake based on LD 50 tests on mice, it is a shy species and rarely strikes, and has not caused any known human fatalities. On the other hand, India's Big Four ( Indian cobra , common krait , Russell's viper, and saw-scaled viper), while less venomous than

1794-594: The puncture wounds, nausea and vomiting, subcutaneous bruising, blood blisters that may form rapidly, and painful swelling of the regional lymph nodes. Swelling usually decreases after a few days, except for the area immediately around the bite site. Hypotension , together with weakness, dizziness, and periods of semi- or unconsciousness is also reported. If not treated carefully, necrosis will spread, causing skin, subcutaneous tissue, and muscle to separate from healthy tissue and eventually slough with serous exudate . The slough may be superficial or deep, sometimes down to

1840-550: The result of convergent evolution . Around a quarter of all snake species are identified as being venomous. Venomous snakes are often said to be poisonous , but poison and venom are not the same thing. Poisons must be ingested, inhaled or absorbed, while venom must be injected into the body by mechanical means. While unusual, there are a few species of snake that are actually poisonous. Keelback snakes are both venomous and poisonous – their poisons are stored in nuchal glands and are acquired by sequestering toxins from poisonous toads

1886-422: The snakes eat. Similarly, certain garter snakes from Oregon can retain toxins in their livers from ingesting rough-skinned newts . Venom toxicities are compared by looking at the median lethal dose (usually using rodents as test animals and termed the murine LD 50 ), which is the dose of venom per unit body mass that kills half of the test animals that receive it. The result obtained depends on which of

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1932-454: The striking position. Mostly nocturnal, they rarely forage actively, preferring, instead, to ambush prey as it happens by. Their prey includes mammals (rodents [ Aethomys sp., Arvicanthis sp., Mastomys sp., Otomys sp., Rattus sp., Rhabdomys pumilio , and Saccostomus campestris ] and even occasionally small deer), birds, amphibians (such as Schismaderma carens ), lizards, other snakes, and tortoises. Females produce

1978-497: The worst prognosis, possibly as a result of its more terrestrial nature (having more potential for human contact), high defensiveness (having a higher possibility to deliver fatal bites instead of dry bites ), large size (giving it a higher strike position proximal to the victim's brain ), and higher average venom yields and potential toxicity (based on experimental results ). A lethality rate of near 100% for untreated black mamba bites has been circulating between various sources, which

2024-472: Was due to a fundamental error in a book called Snakes in Question . In there, all the toxicity testing results were lumped in together, regardless of the mode of testing (e.g., subcutaneous vs. intramuscular vs. intravenous vs. intraperitoneal). As the mode can influence the relative number, venoms can only be compared within a mode. Otherwise, it's apples and rocks." Belcher's sea snake's actual LD 50 (IM)

2070-445: Was found 4.6 m above the ground in a densely branched tree. If disturbed, they hiss loudly and continuously, adopting a tightly coiled defensive posture with the forepart of their body held in a taut "S" shape. At the same time, they may attempt to back away from the threat towards cover. They may strike suddenly and fast, to the side as easily as forwards, before returning quickly to the defensive position, ready to strike again. During

2116-461: Was introduced in 1962, followed by a fully polyvalent antivenom in 1971; over this period, 5 out of 38 people in South Africa bitten by black mambas who received the antivenom died, according to the same report. Since then, the number has significantly dropped with the widespread use of specific antivenom. Despite their fearsome reputation and often exaggerated notoriety, mamba envenomation occurs far less frequently than some other snakes', for instance

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