HOME

TheInfoList



OR:

The puff adder (''Bitis arietans'') is a
viper The Viperidae (vipers) are a family of snakes found in most parts of the world, except for Antarctica, Australia, Hawaii, Madagascar, and various other isolated islands. They are venomous and have long (relative to non-vipers), hinged fangs tha ...
species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
found in
savannah A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the Canopy (forest), canopy does not close. The open canopy allows sufficient light to rea ...
s and
grassland A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
s from
Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to ...
and western
Arabia The Arabian Peninsula, (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") or Arabia, is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plate. ...
throughout
Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...
except for the
Sahara , photo = Sahara real color.jpg , photo_caption = The Sahara taken by Apollo 17 astronauts, 1972 , map = , map_image = , location = , country = , country1 = , ...
and
rainforest Rainforests are characterized by a closed and continuous tree canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforest can be classified as tropical rainforest or temperate rainfores ...
regions.U.S. Navy. 1991. ''Venomous Snakes of the World''. US Govt. New York: Dover Publications Inc. 203 pp. . 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.Spawls S, Howell K, Drewes R, Ashe J. 2004. ''A Field Guide to the Reptiles Of East Africa''. A & C Black Publishers Ltd., London. 543 pp. . Like all other vipers, it is
venomous Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...
. Two
subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
are currently recognized, including the
nominate subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
described here. The species is commonly known as the puff adder,Mallow D, Ludwig D, Nilson G. 2003. ''True Vipers: Natural History and Toxinology of Old World Vipers''. Krieger Publishing Company, Malabar, Florida. 359 pp. .Spawls S, Branch B. 1995. ''The Dangerous Snakes of Africa''. Ralph Curtis Books. Dubai: Oriental Press. 192 pp. . African puff adder,Fichter GS. 1982. ''Venomous Snakes''. (A First Book). Franklin Watts. 66 pp. . Kauffeld C. 1969. ''Snakes: The Keeper and the Kept''. Garden City, New York: Doubleday & Company, Inc. 248 pp. LCCCN 68-27123. or common puff adder.Bitis arietans
a
Munich AntiVenom INdex
Accessed 2 August 2007.


Taxonomy

German naturalist
Blasius Merrem Blasius Merrem (4 February 1761 – 23 February 1824) was a German naturalist, zoologist, ornithologist, mathematician, and herpetologist. In 1804, he became the professor of political economy and botany at the University of Marburg. Early li ...
described the puff adder in 1820. The word ''arietans'' means "striking violently" and is derived from the Latin ''arieto''.''Chambers Murray Latin-English Dictionary'' (1976) The type locality given is "''Promontorio bonae spei''" (
Cape of Good Hope The Cape of Good Hope ( af, Kaap die Goeie Hoop ) ;''Kaap'' in isolation: pt, Cabo da Boa Esperança is a rocky headland on the Atlantic coast of the Cape Peninsula in South Africa. A common misconception is that the Cape of Good Hope is t ...
),
South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...
.


Subspecies


Description

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 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 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 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 the lateral edges.
One unusual specimen, described by Branch and Farrell (1988), from Summer Pride,
East London East or Orient is one of the four cardinal directions or points of the compass. It is the opposite direction from west and is the direction from which the Sun rises on the Earth. Etymology As in other languages, the word is formed from the f ...
, 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 the
Western Cape The Western Cape is a province of South Africa, situated on the south-western coast of the country. It is the fourth largest of the nine provinces with an area of , and the third most populous, with an estimated 7 million inhabitants in 2020 ...
province of South Africa, that usually have a striking yellow-and-black color pattern.


Scalation

The head has a less than triangular shape with a blunt and rounded snout. Still, the head is much wider than the neck. The
rostral scale The rostral scale, or rostral, in snakes and other scaled reptiles is the median plate on the tip of the snout that borders the mouth opening. Wright AH, Wright AA (1957). ''Handbook of Snakes of the United States and Canada''. Ithaca and London: ...
is small. The circumorbital ring consists of 10–16 scales. Across the top of the head, there are 7–11
interocular scales In snakes, the interorbital scales, or intersupraoculars, are the scales on the top of the head between the plates surmounting the eyesWright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates (7th printing, 1985). 1105 pp. . ...
; 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 the chin shields, of which only one pair exists. Often, two fangs are on each
maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The t ...
, and both can be functional. Midbody, the snake has 29–41 rows of
dorsal scales In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales. Campbell JA, Lamar WW (2004). ''The Venomous Reptiles of the Western Hemisphere''. Ithaca and London: Comstock Publis ...
. These are strongly keeled except for the outermost rows. The
ventral scale In snakes, the ventral scales or gastrosteges are the enlarged and transversely elongated scales that extend down the underside of the body from the neck to the anal scale. When counting them, the first is the anteriormost ventral scale that cont ...
count is 123–147, the
subcaudals In snakes, the subcaudal scales are the enlarged plates on the underside of the tail.Wright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates (7th printing, 1985). 1105 pp. . These scales may be either single or divided (pair ...
number 14–38. Females have no more than 24 subcaudals. The
anal scale Anal may refer to: Related to the anus *Related to the anus of animals: ** Anal fin, in fish anatomy ** Anal vein, in insect anatomy ** Anal scale, in reptile anatomy *Related to the human anus: ** Anal sex, a type of sexual activity involv ...
is single.


Distribution and habitat

This species is probably the most common and widespread snake in Africa. It is found in most of
sub-Saharan Africa Sub-Saharan Africa is, geographically, the area and regions of the continent of Africa that lies south of the Sahara. These include West Africa, East Africa, Central Africa, and Southern Africa. Geopolitically, in addition to the List of sov ...
south to the
Cape of Good Hope The Cape of Good Hope ( af, Kaap die Goeie Hoop ) ;''Kaap'' in isolation: pt, Cabo da Boa Esperança is a rocky headland on the Atlantic coast of the Cape Peninsula in South Africa. A common misconception is that the Cape of Good Hope is t ...
, including southern
Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to ...
,
Mauritania Mauritania (; ar, موريتانيا, ', french: Mauritanie; Berber: ''Agawej'' or ''Cengit''; Pulaar: ''Moritani''; Wolof: ''Gànnaar''; Soninke:), officially the Islamic Republic of Mauritania ( ar, الجمهورية الإسلامية ...
,
Senegal Senegal,; Wolof: ''Senegaal''; Pulaar: 𞤅𞤫𞤲𞤫𞤺𞤢𞥄𞤤𞤭 (Senegaali); Arabic: السنغال ''As-Sinighal'') officially the Republic of Senegal,; Wolof: ''Réewum Senegaal''; Pulaar : 𞤈𞤫𞤲𞤣𞤢𞥄𞤲𞤣𞤭 ...
,
Mali Mali (; ), officially the Republic of Mali,, , ff, 𞤈𞤫𞤲𞥆𞤣𞤢𞥄𞤲𞤣𞤭 𞤃𞤢𞥄𞤤𞤭, Renndaandi Maali, italics=no, ar, جمهورية مالي, Jumhūriyyāt Mālī is a landlocked country in West Africa. Mali ...
, southern
Algeria ) , image_map = Algeria (centered orthographic projection).svg , map_caption = , image_map2 = , capital = Algiers , coordinates = , largest_city = capital , relig ...
,
Guinea Guinea ( ),, fuf, 𞤘𞤭𞤲𞤫, italic=no, Gine, wo, Gine, nqo, ߖߌ߬ߣߍ߫, bm, Gine officially the Republic of Guinea (french: République de Guinée), is a coastal country in West Africa. It borders the Atlantic Ocean to the we ...
,
Sierra Leone Sierra Leone,)]. officially the Republic of Sierra Leone, is a country on the southwest coast of West Africa. It is bordered by Liberia to the southeast and Guinea surrounds the northern half of the nation. Covering a total area of , Sierra ...
,
Côte d'Ivoire Ivory Coast, also known as Côte d'Ivoire, officially the Republic of Côte d'Ivoire, is a country on the southern coast of West Africa. Its capital is Yamoussoukro, in the centre of the country, while its largest city and economic centre is ...
,
Ghana Ghana (; tw, Gaana, ee, Gana), officially the Republic of Ghana, is a country in West Africa. It abuts the Gulf of Guinea and the Atlantic Ocean to the south, sharing borders with Ivory Coast in the west, Burkina Faso in the north, and To ...
,
Togo Togo (), officially the Togolese Republic (french: République togolaise), is a country in West Africa. It is bordered by Ghana to the west, Benin to the east and Burkina Faso to the north. It extends south to the Gulf of Guinea, where its c ...
,
Benin Benin ( , ; french: Bénin , ff, Benen), officially the Republic of Benin (french: République du Bénin), and formerly Dahomey, is a country in West Africa. It is bordered by Togo to the west, Nigeria to the east, Burkina Faso to the north ...
,
Niger ) , official_languages = , languages_type = National languagesNigeria Nigeria ( ), , ig, Naìjíríyà, yo, Nàìjíríà, pcm, Naijá , ff, Naajeeriya, kcg, Naijeriya officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf o ...
,
Chad Chad (; ar, تشاد , ; french: Tchad, ), officially the Republic of Chad, '; ) is a landlocked country at the crossroads of North and Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic ...
,
Sudan Sudan ( or ; ar, السودان, as-Sūdān, officially the Republic of the Sudan ( ar, جمهورية السودان, link=no, Jumhūriyyat as-Sūdān), is a country in Northeast Africa. It shares borders with the Central African Republic t ...
,
Cameroon Cameroon (; french: Cameroun, ff, Kamerun), officially the Republic of Cameroon (french: République du Cameroun, links=no), is a country in west-central Africa. It is bordered by Nigeria to the west and north; Chad to the northeast; the C ...
, the
Central African Republic The Central African Republic (CAR; ; , RCA; , or , ) is a landlocked country in Central Africa. It is bordered by Chad to the north, Sudan to the northeast, South Sudan to the southeast, the DR Congo to the south, the Republic of th ...
, northern, eastern, and southern
Democratic Republic of the Congo The Democratic Republic of the Congo (french: République démocratique du Congo (RDC), colloquially "La RDC" ), informally Congo-Kinshasa, DR Congo, the DRC, the DROC, or the Congo, and formerly and also colloquially Zaire, is a country in ...
,
Uganda }), is a landlocked country in East Africa East Africa, Eastern Africa, or East of Africa, is the eastern subregion of the African continent. In the United Nations Statistics Division scheme of geographic regions, 10-11-(16*) territor ...
,
Kenya ) , national_anthem = "Ee Mungu Nguvu Yetu"() , image_map = , map_caption = , image_map2 = , capital = Nairobi , coordinates = , largest_city = Nairobi , ...
,
Somalia Somalia, , Osmanya script: 𐒈𐒝𐒑𐒛𐒐𐒘𐒕𐒖; ar, الصومال, aṣ-Ṣūmāl officially the Federal Republic of SomaliaThe ''Federal Republic of Somalia'' is the country's name per Article 1 of thProvisional Constituti ...
,
Rwanda Rwanda (; rw, u Rwanda ), officially the Republic of Rwanda, is a landlocked country in the Great Rift Valley of Central Africa, where the African Great Lakes region and Southeast Africa converge. Located a few degrees south of the Equator ...
,
Burundi Burundi (, ), officially the Republic of Burundi ( rn, Repuburika y’Uburundi ; Swahili language, Swahili: ''Jamuhuri ya Burundi''; French language, French: ''République du Burundi'' ), is a landlocked country in the Great Rift Valley at the ...
,
Tanzania Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands and ...
,
Angola , national_anthem = " Angola Avante"() , image_map = , map_caption = , capital = Luanda , religion = , religion_year = 2020 , religion_ref = , coordina ...
,
Zambia Zambia (), officially the Republic of Zambia, is a landlocked country at the crossroads of Central Africa, Central, Southern Africa, Southern and East Africa, although it is typically referred to as being in Southern Africa at its most cent ...
,
Malawi Malawi (; or aláwi Tumbuka: ''Malaŵi''), officially the Republic of Malawi, is a landlocked country in Southeastern Africa that was formerly known as Nyasaland. It is bordered by Zambia to the west, Tanzania to the north and northeast ...
,
Mozambique Mozambique (), officially the Republic of Mozambique ( pt, Moçambique or , ; ny, Mozambiki; sw, Msumbiji; ts, Muzambhiki), is a country located in southeastern Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi ...
,
Zimbabwe Zimbabwe (), officially the Republic of Zimbabwe, is a landlocked country located in Southeast Africa, between the Zambezi and Limpopo Rivers, bordered by South Africa to the south, Botswana to the south-west, Zambia to the north, and Mozam ...
,
Botswana Botswana (, ), officially the Republic of Botswana ( tn, Lefatshe la Botswana, label=Setswana, ), is a landlocked country in Southern Africa. Botswana is topographically flat, with approximately 70 percent of its territory being the Kalahar ...
,
Namibia Namibia (, ), officially the Republic of Namibia, is a country in Southern Africa. Its western border is the Atlantic Ocean. It shares land borders with Zambia and Angola to the north, Botswana to the east and South Africa to the south and ea ...
, and South Africa. It also occurs on the
Arabian Peninsula The Arabian Peninsula, (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") or Arabia, is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plate ...
, where it is found in southwestern Saudi Arabia and
Yemen Yemen (; ar, ٱلْيَمَن, al-Yaman), officially the Republic of Yemen,, ) is a country in Western Asia. It is situated on the southern end of the Arabian Peninsula, and borders Saudi Arabia to the Saudi Arabia–Yemen border, north and ...
. It is found in all habitats except true deserts, rainforests, and (tropical) alpine habitats. It is most often associated with rocky grasslands.Mehrtens JM. 1987. ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. . It is not found in rainforest areas, such as along the coast of
West Africa West Africa or Western Africa is the westernmost region of Africa. The United Nations defines Western Africa as the 16 countries of Benin, Burkina Faso, Cape Verde, The Gambia, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia, Mali, Maurit ...
and in
Central Africa Central Africa is a subregion of the African continent comprising various countries according to different definitions. Angola, Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, the Republic of the Congo, ...
(i.e., central DR Congo); it is also absent from the
Mediterranean The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the e ...
coastal region of
North Africa North Africa, or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in ...
. On the Arabian Peninsula, it is found as far north as
Ta'if Taif ( ar, , translit=aṭ-Ṭāʾif, lit=The circulated or encircled, ) is a city and governorate in the Makkan Region of Saudi Arabia. Located at an elevation of in the slopes of the Hijaz Mountains, which themselves are part of the Sarat M ...
. It has been reported to be found in the
Dhofar The Dhofar Governorate ( ar, مُحَافَظَة ظُفَار, Muḥāfaẓat Ẓufār) is the largest of the 11 Governorates in the Sultanate of Oman in terms of area. It lies in Southern Oman, on the eastern border with Yemen's Al Mahrah Gov ...
region of southern
Oman Oman ( ; ar, عُمَان ' ), officially the Sultanate of Oman ( ar, سلْطنةُ عُمان ), is an Arabian country located in southwestern Asia. It is situated on the southeastern coast of the Arabian Peninsula, and spans the mouth of t ...
.


Behaviour

Normally a sluggish species, the puff adder relies on
camouflage Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the ...
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 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 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 the striking position.


Feeding

Mostly nocturnal, they rarely forage actively, preferring, instead, to ambush prey as it happens by. Their prey includes mammals, birds, amphibians, and lizards.


Reproduction

Females produce a pheromone to attract males, which engage in neck-wrestling combat dances. A female in
Malindi Malindi is a town on Malindi Bay at the mouth of the Sabaki River, lying on the Indian Ocean coast of Kenya. It is 120 kilometres northeast of Mombasa. The population of Malindi was 119,859 as of the 2019 census. It is the largest urban centre ...
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 in length. Very large specimens, particularly those from East Africa, give birth to the highest numbers of offspring. A Kenyan female in a
Czech Czech may refer to: * Anything from or related to the Czech Republic, a country in Europe ** Czech language ** Czechs, the people of the area ** Czech culture ** Czech cuisine * One of three mythical brothers, Lech, Czech, and Rus' Places * Czech, ...
zoo gave birth to 156 young, the largest litter for any species of snake.


Captivity

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.


Venom

This species 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 Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder (''Bitis arietans'') or brown recluse spider (''Loxosceles reclusa''). Cell physiology Treating cells ...
effectsWidgerow AD, Ritz M, Song C. 1994. Load cycling closure of fasciotomies following puff adder bite. European Journal of Plastic Surgery 17: 40-42.
Summary
a
Springerlink
Accessed 31 August 2008.
and is one of the most
toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subst ...
of any vipers based on LD50. The values in mice vary: 0.4–2.0 mg/kg
intravenous Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutrie ...
ly, 0.9–3.7 mg/kg peritoneally, and 4.4–7.7 mg/kg
subcutaneously The subcutaneous tissue (), also called the hypodermis, hypoderm (), subcutis, superficial fascia, is the lowermost layer of the integumentary system in vertebrates. The types of cells found in the layer are fibroblasts, adipose cells, and macro ...
(SC).Brown JH. 1973. ''Toxicology and Pharmacology of Venoms from Poisonous Snakes''. Springfield, Illinois: Charles C. Thomas. 184 pp. LCCCN 73-229. . Mallow et al. (2003) give an LD50 range of 1.0–7.75 mg/kg SC. Venom yield is typically 150–350 mg, with a maximum of 750 mg. Brown (1973) mentions a venom yield of 180–750 mg. About 100 mg 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 __NOTOC__ Extravasation is the leakage of a fluid out of its container into the surrounding area, especially blood or blood cells from vessels. In the case of inflammation, it refers to the movement of white blood cells from the capillaries to th ...
, and those with
hemorrhage Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...
s evident as
ecchymosis A bruise, also known as a contusion, is a type of hematoma of tissue, the most common cause being capillaries damaged by trauma, causing localized bleeding that extravasates into the surrounding interstitial tissues. Most bruises occur close e ...
, bleeding, and swelling. In both cases, severe pain and tenderness occur, but in the latter, widespread superficial or deep
necrosis Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated dige ...
and
compartment syndrome Compartment syndrome is a condition in which increased pressure within one of the body's anatomical compartments results in insufficient blood supply to tissue within that space. There are two main types: acute and chronic. Compartments of the ...
are seen. Serious bites cause limbs to become immovably flexed as a result of significant
hemorrhage Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...
or
coagulation Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a blood clot. It potentially results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The mechanism o ...
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 Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's Tissue (biology), tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels t ...
, which may become extensive, shock, watery blood oozing from 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 Hypotension is low blood pressure. Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood. Blood pressure is indicated by two numbers, the systolic blood pressure (the top number) and the dias ...
, together with weakness, dizziness, and periods of semi- or unconsciousness is also reported. If not treated carefully,
necrosis Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated dige ...
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 the bone.
Gangrene Gangrene is a type of tissue death caused by a lack of blood supply. Symptoms may include a change in skin color to red or black, numbness, swelling, pain, skin breakdown, and coolness. The feet and hands are most commonly affected. If the ga ...
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 Disseminated intravascular coagulation (DIC) is a condition in which blood clots form throughout the body, blocking small blood vessels. Symptoms may include chest pain, shortness of breath, leg pain, problems speaking, or problems moving parts o ...
), although some reports show that severe envenomations have a 52% mortality rate. Most fatalities are associated with poor clinical management and neglect.


References


Further reading

*Access Professional Development. 2022. ''Puff Adder (Bitis arietans)''. nlineAvailable: https://accesspd.co.za/species/PuffAdder (Accessed: 02/02/2022) * Boulenger GA. 1896. ''Catalogue of the Snakes in the British Museum (Natural History). Volume III., Containing the...Viperidæ.'' London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers.) xiv + 727 pp. + Plates I.- XXV. (''Bitis arietans'', pp. 493–495.) * Branch, Bill. 2004. ''Field Guide to Snakes and Other Reptiles of Southern Africa''. Third Revised edition, Second impression. Sanibel Island, Florida: Ralph Curtis Books. 399 pp. . (''Bitis arietans'', pp. 114–115 + Plates 3, 12.) * Broadley DG, Cock EV. 1975. ''Snakes of Rhodesia''. Zimbabwe: Longman Zimbabwe Ltd. 97 pp. *Broadley DG. 1990. ''FitzSimons' Snakes of Southern Africa''. Parklands (South Africa): J Ball & AD Donker Publishers. 387 pp. * Merrem B. 1820. ''Versuch eines Systems der Amphibien: Tentamen Systematis Amphibiorum.'' J.C. Krieger. Marburg. xv + 191 pp. + 1 plate.
(''"Vipera. Echidna. arietans"'', p. 152.) *Pienaar U de V. 1978. ''The reptile fauna of Kruger National Park''. National Parks Board of South Africa. 19 pp. *Sweeney RCH. 1961. ''Snakes of Nyasaland''. Zomba, Nyasaland: The Nyasaland Society and Nyasaland Government. 74 pp. *Turner RM. 1972. Snake bite treatment. Black Lechwe 10 (3): 24–33.


External links

* Accessed 9 December 2006. * . Accessed 1 March 2007.
Image of ''B. arietans'' bite that resulted in fasciotomy
a
South African Vaccine Producers
Accessed 26 July 2008.
Birds mob Puff Adder
- paper in ejournal Ornithological Observations {{Taxonbar, from=Q369667 Bitis Snakes of Africa Reptiles of North Africa Reptiles of Ethiopia Reptiles of Uganda Reptiles described in 1820 Taxa named by Blasius Merrem Articles containing video clips