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Superregnum: Eukaryota
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Cladus: Craniata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Superclassis: Tetrapoda
Cladus: Reptiliomorpha
Cladus: Amniota
Classis: Reptilia
Cladus: Eureptilia
Cladus: Romeriida
Subclassis: Diapsida
Cladus: Sauria
Infraclassis: Lepidosauromorpha
Superordo: Lepidosauria
Ordo: Squamata
Subordo: Serpentes
Infraordo: Caenophidia
Superfamilia: Elapoidea

Familia: Elapidae
Genus: Dendroaspis
Species: D. angusticeps – D. jamesoni – D. polylepsis - D. viridis

Name

Dendroaspis Schlegel, 1848
Vernacular names
Akan: Kyerebene
български: Мамби
dansk: Mamba
Deutsch: Mambas
English: Mambas
español: Mambas
suomi: Mambat
français: Mambas
hrvatski: Mambe
italiano: Mamba
日本語: マンバ属
Nederlands: Mamba
norsk: Mambaer
polski: Mamba
português: Mamba
தமிழ்: கருப்பு மாம்பா
ไทย: งูแมมบา
Türkçe: Mamba
中文: 曼巴屬

Mambas are fast moving 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 the black mamba. In Africa there are many legends and stories about mambas.[2][3][4]

Behaviour

The three green species of mambas are arboreal, whereas the black mamba is largely terrestrial. The black mamba is one of the largest and most venomous snakes in Africa. 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.

Mambas and cobras are in the same family: the Elapidae. Like cobras, a mamba may rear and form a hood as part of its threat display, but the mamba's hood is narrower and is longer than the broader hood of some species of cobra, such as say, the spectacled cobras of parts of Asia. In their threat display mambas commonly open their mouths; the black mamba's mouth is black within, which renders the threat more conspicuous. Typically also, a rearing mamba 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.[5] 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.[6] The black mamba usually uses its speed to escape from threats, and humans actually are their main predators, rather than prey.[2]
Venom
A black mamba striking

All mambas are highly venomous. Untreated black mamba bites have a mortality rate of nearly 100%.[7][5][8] The other mamba species are much less dangerous: their venoms are less toxic (based upon LD50 studies); their temperaments generally not as aggressive or as explosive when provoked - and they don't inject as much venom. Fatalities have become much rarer due to wide availability of antivenom.

Mamba venoms contains both pre-synaptic and post-synaptic neurotoxins (the major neurotoxins are known as dendrotoxins). Besides the neurotoxins, they also carry cardiotoxins[2][9] and fasciculins.[10][11] Other components may include calcicludine, which is a known component of the eastern green mamba's venom and calciseptine, which is a component of black mamba venom. Toxicity of individual specimens within the same species and subspecies can vary greatly based on several factors, including diet, geographical region, health/size of the snake, etc. Even the weather and altitude can influence toxicity (Ernst and Zug et al. 1996).

Eastern green mamba envenomation, although rapid in onset of symptoms, is considerably less deadly in comparison to the other three species. Although the Eastern green mamba has caused death, most of the recorded bites in the literature involved mild neurotoxic symptoms and recovery with little to no medical treatment.[7] The Western green mambas (D. viridis and D. jamesonii) are intermediate in severity, causing more severe envenomation than the Eastern green mamba, but less severe than the Black mamba.[12]
Mamba toxins

Mamba toxin (or dendrotoxin) consists of several components, with different targets. Examples are:

Dendrotoxin 1, which inhibits the K+ channels at the pre and post-synaptic level in the intestinal smooth muscle. It also inhibits Ca2+-sensitive K+ channels from rat skeletal muscle‚ incorporated into planar bilayers (Kd = 90 nM in 50 mM KCl).[13])
Dendrotoxin 3, which inhibits acetylcholine M4 receptors.[14]
Dendrotoxin 7, commonly referred to as muscarinic toxin 7 (MT7) inhibits acetylcholine M1 receptors.[14]
Dendrotoxin K, structurally homologous to Kunitz-type proteinase inhibitors[15] with activity as a selective blocker of voltage-gated potassium channels[16]

Taxonomy

Dendroaspis, is derived from Ancient Greek déndron (δένδρον), meaning "tree",[17] and aspis (ασπίς), which is understood to mean "shield",[18] 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.[19] The genus was first described by the German naturalist Hermann Schlegel in 1848,[20] with Elaps jamesonii as 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 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.[21] However, in 1962 German herpetologist Robert Mertens proposed that the 1843 description of Dendraspis by Fitzinger be suppressed due to its similarity to Dendroaspis, and the confusion it would cause by its use.[22]
Range and characteristics

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.[2][6]

Species[23] Authority[23][a] Image Subsp.*[23] Common name Geographic range
Dendroaspis angusticeps (Smith, 1849) Mamba Dendroaspis angusticeps.jpg 0 Eastern green mamba Found in Kenya, Tanzania, Malawi, Mozambique, Zimbabwe, Swaziland, eastern South Africa
Dendroaspis jamesoniT (Traill, 1843) JamesonsMamba.jpg 2 Jameson's mamba Found in Central Africa in South Sudan, Gabon, Angola, Zambia, Republic of the Congo, Democratic Republic of the Congo, Cameroon, Equatorial Guinea, Nigeria, Kenya, Uganda, Rwanda, Burundi, Tanzania, Central African Republic, Benin, Togo, Ghana
Dendroaspis polylepis Günther, 1864 Dendroaspis polylepis (14).jpg 0 Black mamba Found in northern Central Africa to eastern Africa and southern Africa in Cameroon, northern Republic of the Congo, Central African Republic, northeast Democratic Republic of the Congo, and southwestern Sudan to Ethiopia, Eritrea, Djibouti, Somalia, Kenya, eastern Uganda, Rwanda, Burundi, Tanzania, southwards to Mozambique, Swaziland, Malawi, Zambia, Zimbabwe, Lesotho, and Botswana to KwaZulu-Natal in South Africa, and Namibia; then northeasterly through Angola to the southeastern part of the Democratic Republic of Congo
Dendroaspis viridis (Hallowell, 1844) Dendroaspis viridisPCCA20051227-1885B.jpg 0 Western green mamba Found only in western Africa in southern Senegal, Gambia, Guinea-Bissau, Guinea, Sierra Leone, Liberia, Côte d’Ivoire, Ghana, Togo, Benin, and southwest Nigeria

* Including the nominate subspecies.
T Type species.
Phylogeny

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.[24][25]

Ophiophagus hannah

D. j. jamesoni

D. j. kaimosae

D. viridis

D. angusticeps

D. polylepis



Notes

A binomial authority in parentheses indicates that the species was originally described in a genus other than Dendroaspis.

References

"Dendroaspis". Integrated Taxonomic Information System. Retrieved 30 October 2012.
"National Geographic (Black Mamba, Dendroaspis polylepis)". National Geographic Society. 10 September 2010. Retrieved 17 October 2020. "African myths exaggerate their capabilities to legendary proportions; Black mambas are shy and will almost always seek to escape when confronted."
Jan Knappert (1 January 1985). Myths and Legends of Botswana, Lesotho, and Swaziland. Brill Archive. pp. 53–. ISBN 90-04-07455-4.
Alfred Burdon Ellis (1887). South African Sketches. Chapman and Hall, Limited. also at: [1]
O'Shea, Mark (2005). VENOMOUS SNAKES OF THE WORLD. multiple places: US and Canada: Princeton University Press; Europe: New Holland (UK) Ltd. pp. 78–79. ISBN 978-0-691-15023-9. "...in common with other snakes they prefer to avoid contact;...Of the three species of green mambas...;...from 1957 to 1963...including all seven black mamba bites - a 100 per cent fatality rate"
The new encyclopedia of Reptiles (Serpent). Time Book Ltd. 2002.
Branch, W (January 1979). "The venomous snakes of southern Africa Part 2. Elapidae and Hydrophidae". The Snake. 11 (2): 199–225. Retrieved 1 July 2021.
Davidson, Terence. "Immediate First Aid". University of California, San Diego. Archived from the original on 2012-11-02. Retrieved 2011-09-22.
van Aswegen G, van Rooyen JM, Fourie C, Oberholzer G. (May 1996). "Putative cardiotoxicity of the venoms of three mamba species". Wilderness & Environmental Medicine. 7 (2): 115–21. doi:10.1580/1080-6032(1996)007[0115:PCOTVO]2.3.CO;2. PMID 11990104.
Fasciculin
"Neurotoxins in Snake Venom". Retrieved 2019-12-26.
Warrell, DA (1995). Meier, J; White, J (eds.). Handbook of Clinical Toxicology of Animal Venoms and Poisons (1 ed.). Boca Raton: CRC Press. pp. 433–492. ISBN 9781351443142.
Newitt RA, Houamed KM, Rehm H, Tempel BL. (1991). "[Potassium channels and epilepsy: evidence that the epileptogenic toxin, dendrotoxin, binds to potassium channel proteins.]". Epilepsy Research Supplement. 4: 263–73. PMID 1815606.
Rang, H. P. (2003). Pharmacology. Edinburgh: Churchill Livingstone. p. 139. ISBN 0-443-07145-4.
Berndt KD, Güntert P, Wüthrich K. (5 December 1993). "[Nuclear magnetic resonance solution structure of dendrotoxin K from the venom of Dendroaspis polylepis polylepis.]". Journal of Molecular Biology. 234 (3): 735–50. doi:10.1006/jmbi.1993.1623. PMID 8254670.
Harvey AL, Robertson B. (2004). "Dendrotoxins: structure-activity relationships and effects on potassium ion channels". Curr. Med. Chem. 11 (23): 3065–72. doi:10.2174/0929867043363820. PMID 15579000.
"dendro-". Collins English Dictionary - Complete & Unabridged 10th Edition. HarperCollins Publishers. Retrieved 4 March 2014.
"Definition of "aspis" - Collins English Dictionary". collinsdictionary.com. Retrieved 15 February 2015.
"aspis, asp". Dictionary.com Unabridged. Random House. Retrieved 4 March 2014.
"Dendroaspis". Integrated Taxonomic Information System. Retrieved 9 December 2013.
Brongersma, Leo Daniel (1936). "Herpetological note XIII". Zoo. Mededeel. 19: 135.
Mertens, Robert (1962). "Dendraspis Fitzinger, 1843 (Reptilia, Serpentes); Proposed Suppression under the Plenary Powers. Z.N. (S.) 1500" (PDF). Bulletin of Zoological Nomenclature. 19: 189–190.
"Dendroaspis". Integrated Taxonomic Information System. Archived from the original on 12 March 2009. Retrieved 5 July 2013.
Ainsworth, Stuart; Petras, Daniel; Engmark, Mikael; Süssmuth, Roderich D.; Whiteley, Gareth; Albulescu, Laura-Oana; Kazandjian, Taline D.; Wagstaff, Simon C.; Rowley, Paul; Wüster, Wolfgang; Dorrestein, Pieter C.; Arias, Ana Silvia; Gutiérrez, José M.; Harrison, Robert A.; Casewell, Nicholas R.; Calvete, Juan J. (2018). "The medical threat of mamba envenoming in sub-Saharan Africa revealed by genus-wide analysis of venom composition, toxicity and antivenomics profiling of available antivenoms". Journal of Proteomics. 172: 173–189. doi:10.1016/j.jprot.2017.08.016. PMID 28843532.
Figueroa, A.; McKelvy, A. D.; Grismer, L. L.; Bell, C. D.; Lailvaux, S. P. (2016). "A species-level phylogeny of extant snakes with description of a new colubrid subfamily and genus". PLOS ONE. 11 (9): e0161070. Bibcode:2016PLoSO..1161070F. doi:10.1371/journal.pone.0161070. PMC 5014348. PMID 27603205.

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