''Bothrops atrox'' — also known as the common lancehead, ''fer-de-lance'', ''barba amarilla'',Campbell JA, Lamar WW. 2004. ''The Venomous Reptiles of the Western Hemisphere''. Comstock Publishing Associates, Ithaca and London. 870 pp. 1500 plates. and ''mapepire balsain'' — is a highly

venom 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 ...

ous

pit viper The Crotalinae, commonly known as pit vipers,Mehrtens JM (1987). ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. . or pit adders, are a subfamily (biology), subfamily of Viperidae, vipers found in Asia and the ...

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

found in the tropical lowlands of northern

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

east of the

Andes The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...

, as well as the

Caribbean The Caribbean ( , ; ; ; ) is a region in the middle of the Americas centered around the Caribbean Sea in the Atlantic Ocean, North Atlantic Ocean, mostly overlapping with the West Indies. Bordered by North America to the north, Central America ...

island of

Trinidad Trinidad is the larger, more populous island of the Republic of Trinidad and Tobago, the country. The island lies off the northeastern coast of Venezuela and sits on the continental shelf of South America. It is the southernmost island in ...

. No subspecies are currently recognized.

Taxonomy

The common lancehead was one of the many reptile and amphibian species described by

Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

in the landmark 1758

10th edition 1 (one, unit, unity) is a number, numeral, and glyph. It is the first and smallest positive integer of the infinite sequence of natural numbers. This fundamental property has led to its unique uses in other fields, ranging from science to sp ...

of his ''

Systema Naturae ' (originally in Latin written ' with the Orthographic ligature, ligature æ) is one of the major works of the Sweden, Swedish botanist, zoologist and physician Carl Linnaeus (1707–1778) and introduced the Linnaean taxonomy. Although the syste ...

'', where it was given the binomial name ''Coluber atrox''. The

taxonomy image:Hierarchical clustering diagram.png, 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme o ...

of this species is controversial; it may include '' B. leucurus'' and '' B. moojeni'', and some of its populations are sometimes said to be separate species. '' B. asper'' was formerly included in this species, but most authorities now consider it distinct.

Names

Common names include lancehead, ''fer-de-lance'', ''barba amarilla'', and ''mapepire balsain'', among others. The

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many countries in the Americas **Spanish cuisine **Spanish history **Spanish culture ...

common name ''barba amarilla'' (yellow beard), an allusion to the pale-yellow chin color, is also used in English. In

Venezuela Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...

, it is called ''mapanare''. In

Colombia Colombia, officially the Republic of Colombia, is a country primarily located in South America with Insular region of Colombia, insular regions in North America. The Colombian mainland is bordered by the Caribbean Sea to the north, Venezuel ...

, it is known as ''mapaná '' (Llanos of Vichada) and ''talla equis''. In

Guyana Guyana, officially the Co-operative Republic of Guyana, is a country on the northern coast of South America, part of the historic British West Indies. entry "Guyana" Georgetown, Guyana, Georgetown is the capital of Guyana and is also the co ...

and

Suriname Suriname, officially the Republic of Suriname, is a country in northern South America, also considered as part of the Caribbean and the West Indies. It is a developing country with a Human Development Index, high level of human development; i ...

, it is called ''labaria'' or ''labarria''. In

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

, it is called ''aroani'' (Yagua), ''cascabel'' (juveniles), ''ihdóni'' (Bora), ''jergón'', ''jergona'', ''jergón de la selva'', ''macánchi'' (Alto Marañón), ''machacú'', ''marashar'' and ''nashipkit'' (Aguaruna names). The name ''jergón'' is an allusion to the X-like markings of the color pattern. In

Ecuador Ecuador, officially the Republic of Ecuador, is a country in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean on the west. It also includes the Galápagos Province which contain ...

and

Panama Panama, officially the Republic of Panama, is a country in Latin America at the southern end of Central America, bordering South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and ...

, these markings have led to the snake simply being referred to as ''equis'' (the Spanish name of the letter 'x'). In Trinidad, it is known as ''mapepire balsain''. In Bolivia, it is called ''Yoperojobobo''. In Brazil, the common names are ''jararaca'' or ''Jararaca-do-norte''. The name ''fer-de-lance'' comes from

French French may refer to: * Something of, from, or related to France ** French language, which originated in France ** French people, a nation and ethnic group ** French cuisine, cooking traditions and practices Arts and media * The French (band), ...

, meaning, "head of a lance", "

spear A spear is a polearm consisting of a shaft, usually of wood, with a pointed head. The head may be simply the sharpened end of the shaft itself, as is the case with Fire hardening, fire hardened spears, or it may be made of a more durable materia ...

head", or literally "lance iron".

Description

A terrestrial species, adults usually grow to a total length 75–125 cm (about 30-50 inches) and are moderately heavy-bodied. Reports of the maximum size are not clear, as this species is often confused with '' B. asper''. Soini (1974) mentioned of a series of 80 specimens collected in northeastern Peru, the largest was a female of . The largest specimen measured by Campbell and Lamar (2004) was a female with a total length of . The scalation includes 23-29 (usually 23-25) 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 ...

at midbody, 169-214 and 177-214

ventral scales 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 ...

in males and females, respectively, 52-86 (usually 75 or fewer)

subcaudal scales In snakes, the subcaudal scales are the enlarged plates on the underside of the tail. Wright AH, Wright AA (1957). ''Handbook of Snakes of the United States and Canada''. Comstock Publishing Associates, a Division of Cornell University Press. (7t ...

in males, which are usually divided, and 47-72 subcaudals in females. On the head, 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 about as high, or slightly higher, than it is wide. There are three to 11 (usually five to 9) keeled

intersupraocular 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. . ( ...

, seven to 13 (usually eight to 11)

sublabial scales In reptiles, the sublabial scales, also called lower-labials or infralabials, are those scales that border the mouth opening along the lower jaw. They do not include the median scaleWright AH, Wright AA. 1957. ''Handbook of Snakes''. Comstock Publis ...

and six to 9 (usually seven)

supralabial scales In reptiles, the supralabial scales, also called upper-labials, are those scales that border the mouth opening along the upper jaw. They do not include the median scaleWright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates ( ...

, the second of which is fused with the

prelacunal Lacunal scales are those scales that form the inner border of the loreal pit The loreal pit is the deep depression, or fossa, in the Lore (anatomy), loreal area on either side of the head in pit vipers (crotaline snakes). The area is located be ...

to form a

lacunolabial The lacunolabial scale is a large scale that forms in some crotaline snakes (pitvipers) when the prelacunal scale fuses with the second (rarely the third) supralabial scale. In such cases, it is often said that "the second labial enters the pi ...

. The color pattern is highly variable, including a ground color that may be olive, brown, tan, gray, yellow, or (rarely) rusty. The body markings are highly variable, as is the degree of contrast; in some specimens, the pattern is very well defined, while in others, it may be virtually absent. In general, however, the body pattern consists of a series of dorsolateral blotches, rectangular or trapezoidal in shape, which extend from the first scale row to the middle of the back. These blotches may oppose or alternate across the midline, often fusing to form bands. They also have pale borders, which in some cases may be prominent, and may be invaded from below by tan or gray pigment, occasionally dividing them into pairs of ventrolateral spots. The belly may be white, cream, or yellowish gray, with an increasing amount of gray to black mottling posteriorly that may fade again under the tail. The head usually does not have any markings other than a moderately wide postocular stripe that runs from behind the eye back to the angle of the mouth. The irises are gold or bronze, with varying amounts of black reticulation, while the tongue is black.

Distribution and habitat

This species is found in the tropical lowlands of South America east of the Andes, including southeastern

, southern and eastern

, the island of Trinidad (although some confusion exists regarding the taxonomical systematics of this population),

French Guiana French Guiana, or Guyane in French, is an Overseas departments and regions of France, overseas department and region of France located on the northern coast of South America in the Guianas and the West Indies. Bordered by Suriname to the west ...

, eastern

, northern

Bolivia Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, w ...

, and the northern half of

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

. The type locality is listed as "Asia", which is obviously a mistake. Schmidt and Walker (1943:295) proposed this be corrected to "Surinam". Despite the vast destruction of rain forests, it is among the most numerous and common of

pit vipers The Crotalinae, commonly known as pit vipers,Mehrtens JM (1987). ''Living Snakes of the World in Color''. New York: Sterling Publishers. 480 pp. . or pit adders, are a subfamily of vipers found in Asia and the Americas. Like all other vipers, ...

and is not endangered. In Trinidad, it prefers wet forests from sea level to .Herklots GAC. 1961. ''The Birds of Trinidad and Tobago''. Collins, London, p. 10. Along with '' Bothrops caribbaeus'' and '' B. lanceolatus'', it is one of three ''Bothrops'' species found in the

West Indies The West Indies is an island subregion of the Americas, surrounded by the Atlantic Ocean, North Atlantic Ocean and the Caribbean Sea, which comprises 13 independent island country, island countries and 19 dependent territory, dependencies in thr ...

Behavior

Although generally

terrestrial Terrestrial refers to things related to land or the planet Earth, as opposed to extraterrestrial. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on o ...

, it is also an excellent swimmer and even climbs trees when necessary to reach prey. Generally

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

, it may forage at any time of the day, though, if necessary. These snakes are also easily agitated.

Feeding

Their main diet includes mostly small mammals (such as rodents and opossums) and birds, but also frogs, lizards, smaller snakes, fish, crayfish, centipedes, and tarantulas. Larger prey is struck and released, after which it is tracked down by its scent trail.

Reproduction

''Bothrops atrox'' can give live birth to up to 80 offspring at once. Adults breed year-round. After mating, females with developing

embryos An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male spe ...

travel in and out of sunlight to keep themselves and the embryos at a constant temperature. In

equator The equator is the circle of latitude that divides Earth into the Northern Hemisphere, Northern and Southern Hemisphere, Southern Hemispheres of Earth, hemispheres. It is an imaginary line located at 0 degrees latitude, about in circumferen ...

ial regions, the gestation period is about three to four months, with an average of 60 young per litter. At birth, the young are about in total length, more brightly colored than adults, and have

yellow Yellow is the color between green and orange on the spectrum of light. It is evoked by light with a dominant wavelength of roughly 575585 nm. It is a primary color in subtractive color systems, used in painting or color printing. In t ...

beige Beige ( ) is variously described as a pale sandy fawn color, a grayish tan, a light-grayish yellowish brown, or a pale to grayish yellow. It takes its name from French, where the word originally meant natural wool that has been neither ble ...

tails. Three species of the Neotropical

''Bothrops atrox'' group were confirmed to undergo facultative

parthenogenesis Parthenogenesis (; from the Greek + ) is a natural form of asexual reproduction in which the embryo develops directly from an egg without need for fertilization. In animals, parthenogenesis means the development of an embryo from an unfertiliz ...

on the basis of captivity information and by the use of molecular markers (heterologous

microsatellites A microsatellite is a tract of repetitive DNA in which certain DNA motifs (ranging in length from one to six or more base pairs) are repeated, typically 5–50 times. Microsatellites occur at thousands of locations within an organism's genome. T ...

). Infertile eggs, non-viable ova and malformed offspring were frequent in those cases.

Venom

These snakes are known to search for

rodents 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 n ...

coffee Coffee is a beverage brewed from roasted, ground coffee beans. Darkly colored, bitter, and slightly acidic, coffee has a stimulating effect on humans, primarily due to its caffeine content, but decaffeinated coffee is also commercially a ...

and

banana A banana is an elongated, edible fruit – botanically a berry – produced by several kinds of large treelike herbaceous flowering plants in the genus '' Musa''. In some countries, cooking bananas are called plantains, distinguishing the ...

plantations. Workers there are often bitten by the snakes, which can lie camouflaged for hours, nearly undetectable, and strike with high speed. Their venom is hemorrhagic, damaging the vascular endothelium and consuming coagulation factors in a mechanism known as venom-induced consumption coagulopathy. As a result, clotting assays such as

prothrombin time The prothrombin time (PT) – along with its derived measures of prothrombin ratio (PR) and international normalized ratio (INR) – is an assay for evaluating the Coagulation#Extrinsic pathway, extrinsic pathway and Coagulation#Common pathway, ...

and

aPTT The partial thromboplastin time (PTT), also known as the activated partial thromboplastin time (aPTT or APTT), is a blood test that characterizes coagulation of the blood. A historical name for this measure is the Kaolin-cephalin clotting time ...

will be highly disturbed. Spontaneous recovery from coagulopathy is seen 14 to 30 hours after bite according to a study performed in French Guiana. A Mexican polyvalent antivenom was tested, but had no effect on it. ''B. atrox'' venom can result in several systemic and local symptoms, such as severe bleeding, kidney failure, abnormal clotting, blisters, and necrosis. The bite can also result in hemorrhage in the central nervous system, which leads to sequelae and even death. In a case reported in the Brazilian Amazon, symptoms such as pain and

ecchymoses 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 c ...

headaches A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of depression in those with severe headaches. Head ...

nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. It can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the throat. Over 30 d ...

vomiting Vomiting (also known as emesis, puking and throwing up) is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Vomiting can be the result of ailments like food poisoning, gastroenteritis, pre ...

diarrhea Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ...

hypertension Hypertension, also known as high blood pressure, is a Chronic condition, long-term Disease, medical condition in which the blood pressure in the artery, arteries is persistently elevated. High blood pressure usually does not cause symptoms i ...

, and blood incoagulability were reported, the patient died of

stroke Stroke is a medical condition in which poor cerebral circulation, blood flow to a part of the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemor ...

, even after administration of the antivenom. The common lancehead has an LD₅₀ of 1.1 to 4.9 mg/kg; the venom of juveniles is more inflammatory, lethal, and hemorrhagic, and kills more quickly than that of adults. People bitten by neonates are more likely to develop

coagulopathy Coagulopathy (also called a bleeding disorder) is a condition in which the blood's ability to coagulate (form clots) is impaired. This condition can cause a tendency toward prolonged or excessive bleeding ( bleeding diathesis), which may occur s ...

. Venom yield averages , although it may be as much as . The enzyme reptilase (batroxobin), derived from this snake's venom, is used in modern medical laboratories to measure fibrinogen levels and blood coagulation capability. The test is considered to be a replacement for thrombin time, and is used when heparin is present in the sample. The enzyme is unaffected by heparin.

References

External links

* {{Taxonbar , from=Q900848

atrox Atrox is a Norwegian avant-garde metal band from Trondheim. The group originally formed under the name "Suffocation" but soon changed it because of numerous other bands with the same name.Biography AllMusic Formed in 1988, the band released its fi ...

Snakes of the Caribbean Reptiles of Bolivia Snakes of Brazil Reptiles of Colombia Reptiles of Ecuador Reptiles of French Guiana Reptiles of Trinidad and Tobago Reptiles of Guyana Reptiles of Panama Reptiles of Peru Reptiles of Suriname Reptiles of Venezuela Reptiles described in 1758 Taxa named by Carl Linnaeus