The berg adder (''Bitis atropos'') is a

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 ...

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 ...

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to mountainous regions in

southern Africa Southern Africa is the southernmost subregion of the African continent, south of the Congo and Tanzania. The physical location is the large part of Africa to the south of the extensive Congo River basin. Southern Africa is home to a number of ...

. No

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.

Taxonomy

The specific name, ''atropos'', refers to the Greek mythological goddess

Atropos Atropos (; grc, Ἄτροπος "without turn") or Aisa, in Greek mythology, was one of the three Moirai, goddesses of fate and destiny. Her Roman equivalent was Morta. Atropos was the oldest of the Three Fates, and was known as "the Inflex ...

, who was one of the Three Fates, the one who cut the thread of life. The type locality given is "America", but this is obviously a mistake. More likely, it is 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 ...

, according to

FitzSimons Fitzsimons (also spelled FitzSimons, Fitzsimmons or FitzSimmons) is a surname of Norman origin common in both Ireland and England. The name is a variant of "Sigmundsson", meaning son of Sigmund. The Gaelicisation of this surname is Mac Shíomóin. ...

(1962). Its common names include berg adder,Spawls S, Branch B (1995). ''The Dangerous Snakes of Africa''. Dubai: Oriental Press / Ralph Curtis Books. 192 pp. . Cape mountain adder, and mountain adder.Mallow D, Ludwig D, Nilson G (2003). ''True Vipers: Natural History and Toxinology of Old World Vipers''. Malabar, Florida: Krieger Publishing Company. 359 pp. .''

Description

The typical adult size of ''B. atropos'' is 30–40 cm (about 12–16 in) in total length (body and tail), with some females reaching a maximum total length of in the wild and in captivity.

Distribution and habitat

''B. atropos'' is found in isolated populations of the mountainous regions of

. In

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 ...

, the species is known to occur in the

Transvaal Transvaal is a historical geographic term associated with land north of (''i.e.'', beyond) the Vaal River in South Africa. A number of states and administrative divisions have carried the name Transvaal. * South African Republic (1856–1902; af, ...

, along the Drakensberg escarpment of the eastern and northern Transvaal. Elsewhere in South Africa, it occurs in western

Natal NATAL or Natal may refer to: Places * Natal, Rio Grande do Norte, a city in Brazil * Natal, South Africa (disambiguation), a region in South Africa ** Natalia Republic, a former country (1839–1843) ** Colony of Natal, a former British colony ( ...

Lesotho Lesotho ( ), officially the Kingdom of Lesotho, is a country landlocked country, landlocked as an Enclave and exclave, enclave in South Africa. It is situated in the Maloti Mountains and contains the Thabana Ntlenyana, highest mountains in Sou ...

, and eastern Free State, and in the southern coastal mountains of western and eastern

Cape Province The Province of the Cape of Good Hope ( af, Provinsie Kaap die Goeie Hoop), commonly referred to as the Cape Province ( af, Kaapprovinsie) and colloquially as The Cape ( af, Die Kaap), was a province in the Union of South Africa and subsequen ...

. Spawls and Branch (1995) also mentioned, in Cape Province, its range extends into the

Cape Peninsula The Cape Peninsula ( af, Kaapse Skiereiland) is a generally mountainous peninsula that juts out into the Atlantic Ocean at the south-western extremity of the African continent. At the southern end of the peninsula are Cape Point and the Cape of ...

.Berg adder (''Bitis atropos'')
It also occurs in

Eswatini Eswatini ( ; ss, eSwatini ), officially the Kingdom of Eswatini and formerly named Swaziland ( ; officially renamed in 2018), is a landlocked country in Southern Africa. It is bordered by Mozambique to its northeast and South Africa to its no ...

, in higher altitudes of eastern Zimbabwe such as the Inyanga Highlands and

Chimanimani Mountains The Chimanimani Mountains are a mountain range on the border of Zimbabwe and Mozambique. The mountains are in the southern portion of the Eastern Highlands, or Manica Highlands, a belt of highlands that extend north and south along the internatio ...

, and in nearby

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 ...

. ''B. atropos'' occupies a number of different

habitats In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

, but prefers relatively cool environments with high levels of precipitation. In the northern part of its range, where the winters are cold and dry and the summers warm and wet, it is restricted to higher elevations, up to . In Zimbabwe, it is not found below , usually associated with mountain slopes and rocky hillsides, but also montane

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 ...

with patches of bushes and shrubs. In the southern part of its range (Cape Province, South Africa), where the winters are cold and wet and the summers warm and dry, it can be found in coastal and mountain heathland, as well as small rock outcrops at sea level and grassy areas with clumps of bushes and shrubs west of the

Venom and diet

The atropos adder is unusual among ''Bitis'' species in that its venom is predominantly

neurotoxic Neurotoxicity is a form of toxicity in which a biological, chemical, or physical agent produces an adverse effect on the structure or function of the central and/or peripheral nervous system. It occurs when exposure to a substance – specificall ...

, so much so that the effects of the bite seldom include

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 ...

or infection. The snake is described as "irascible", hissing violently and twisting convulsively if molested.Rose, Walter (1950). ''The Reptiles and Amphibians of Southern Africa''. Maskew Miller. Presumably, the neurotoxic venom is an adaptation to the

prey Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...

, which largely comprise rock

lizard Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt ...

s and small

amphibian Amphibians are tetrapod, four-limbed and ectothermic vertebrates of the Class (biology), class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terres ...

s. It does, however, also eat other animals, such as small

rodent Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are na ...

s and young of ground-nesting

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

s. The venom is not powerful enough for the dose injected at a single strike to kill an adult human, and no records of human fatalities have been found. Whether at threat or not, though, persons do not seem to respond usefully to antivenom, so treatment should be limited to symptomatic control. Such as the effects of the venom are, they take effect quickly. Symptoms of the bite have been compared to alcohol intoxication and are not permanent. Unlike the bites of elapid snakes, ''B. atropos'' bites, though neurotoxic, do not cause obvious effects on heart and respiratory functions, but they can be troublesome, and their effects sometimes persist for some days or even weeks, which suggests the venom causes nerve damage that does not mend quickly if it is severe. Obvious symptoms may include loss of smell or taste, drooping eyelids, and loss of vision.

Reproduction

''B. atropos'' is

viviparous Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the m ...

. Young are born in late summer. Average litter size is seven, but may be as many as 15. Each neonate has a total length (including tail) of about .Branch, Bill (2004).

References

External links

*''Bitis atropos'' a
Eco Travel Africa
Accessed 27 October 2011. {{Taxonbar, from=Q2704831 Bitis Snakes of Africa Reptiles described in 1758 Reptiles of Lesotho Reptiles of Mozambique Reptiles of South Africa Reptiles of Eswatini Reptiles of Zimbabwe Taxa named by Carl Linnaeus