Animal Diversity Web

Ge­o­graphic Range

Both­ri­op­sis bi­lin­eata is found in the South Amer­i­can neotrop­ics. The largest pop­u­la­tions are found in the Ama­zon­ian re­gions of Bo­livia, Co­lum­bia, Equador, Peru, and Brazil. Other highly pop­u­lated re­gions in­clude equa­to­r­ial forests of Venezuela, Guyana, French Guiana, and Suri­name. It is most abun­dant in south­west South Amer­ica, in Par­que Na­cional. Both­ri­op­sis bi­lin­eata has been doc­u­mented as far south as Jacarepagua, which is lo­cated within the city lim­its of Rio de Janeiro. How­ever, the species was re­moved from Jacarepagua in 1963 and is now con­sid­ered rare in that re­gion. ("Ven­omous An­i­mals and Plants", 2008; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004)

• Biogeographic Regions
• neotropical
  • native

Habi­tat

Two-striped for­est-pitvipers are pre­sent only in forested habi­tats. Its dis­tri­b­u­tion ranges from sea level to ap­prox­i­mately 1000 m in el­e­va­tion. They very sel­dom are found at el­e­va­tions above 1000 m. Their most com­mon habi­tat is wet low­land rain­forests, where they live pri­mar­ily near wa­ter­ways, es­pe­cially along streams. Two-striped for­est-pitvipers spend much of their time on branches and shrubs more than 1 m off the ground. While they are par­tic­u­larly abun­dant in very wet pri­mary forests, these snakes also occur in sec­ondary forests near or ad­ja­cent to pri­mary forests. Wet low­land rain­forests oc­cu­pied by two-striped for­est-pitvipers usu­ally have a canopy height of 40 m, but in­di­vid­ual trees can reach up to 65 m. How­ever, trees in wet low­land rain­forests typ­i­cally have a greater height, height to first branch, trunk vol­ume, but­tress height and but­tress area than in other rain­for­est ecosys­tems. Sub-canopy veg­e­ta­tion in low­land rain­forests pri­mar­ily con­sists of suc­ces­sional trees rather than shrubs or herbs. ("Ven­omous An­i­mals and Plants", 2008; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Daly and Mith­cell, 2000)

• Habitat Regions
• tropical

• Terrestrial Biomes
• forest
• rainforest

• Other Habitat Features
• riparian

• Range elevation

  0 to 1000 m

  0.00 to 3280.84 ft

Phys­i­cal De­scrip­tion

Both­ri­op­sis bi­lin­eata is a sleek, green pitviper with a pre­hen­sile tail. Typ­i­cal length is about 70 cm, al­though in­di­vid­u­als up to 123 cm have been re­ported. Fe­males are usu­ally 10 to 20 cm longer than males. In both sexes, the head is typ­i­cally green with black spots, but some­times may be green with tan or red spots with black mar­gins. The iris of the eye is light green to yel­low and the pupil is ver­ti­cally el­lip­ti­cal. The tongue is pink­ish-grey with dark grey tips. Snout length in B. bi­lin­eata is sim­i­lar to that of other pit vipers, with a well de­fined can­thus ros­tralis. Body col­oration of in B. bi­lin­eata is pale green with black, red, or tan spots, on the dor­sum. The en­larged scales on ven­ter, com­monly re­ferred to as ven­trals, are yel­low with a green tinged bor­der­ing. A creamy yel­low line bor­ders the lat­eral mar­gins of the ven­trals and runs the en­tire length of the snake. The dis­tal por­tion of the tail is pink out­lined by yel­low. In­di­vid­u­als with a whitish-yel­low tail tip have been re­ported. (Mon­teiro, et al., 2006; Val­dujo, et al., 2002; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Mon­teiro, et al., 2006; Val­dujo, et al., 2002)

The two-striped for­est pitviper are pri­mar­ily ar­bo­real. They weigh less and are a no­tably shorter in length than other species of pitviper. This dif­fer­ence in length has been at­trib­uted both to their ar­bo­real habi­tat and feed­ing be­hav­ior. Smaller body size al­lows them to ar­tic­u­late through the dense shrub­bery of the Ama­zon re­gion. (Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Mon­teiro, et al., 2006; Val­dujo, et al., 2002)

Other char­ac­ter­is­tic fea­tures of Both­ri­op­sis bi­lin­eata in­clude 5 to 9 keeled in­ter­supraoc­u­lars, 7 to 9 supral­abi­als, 8 to 12 in­fral­abi­als, and 23 to 25 mid­body scale rows. Males have 190 to 218 ven­trals and 65 to 76 mostly di­vided sub­cau­dals, whereas fe­males have 192 to 220 ven­trals and 55 to 73 mostly di­vided sub­cau­dals. Usu­ally B. bi­lin­eata has a la­cuno­labial that is formed by the sec­ond supral­abial and prela­cu­nal fused to­gether. How­ever, some­times pre­sent are par­tial or full su­tures that sep­a­rate these scales form­ing the la­cuno­labial. Mem­bers of the genus Both­ri­op­sis have unique skull mor­phol­ogy in that the frontal bones are con­cave and are longer than than they are wide. The post­frontals do not con­tact the frontal bones and are long and nar­row. All pitvipers have 5 pala­tine teeth, 14 to 18 ptery­goid teeth, and 15 to 17 den­tary teeth. Their max­il­lary fangs are around 1.5 to 2 times longer than the height of the max­il­lary bone. (Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Mon­teiro, et al., 2006; Val­dujo, et al., 2002)

Re­lated or sim­i­lar species to Both­ri­op­sis bi­lin­eata in­cludes sub­species B. b. smaragdi­nus, which dif­fers in that it does not pos­sess tan or red spots on its body. Rather, it is pep­pered only with black spots. One other pre­hen­sile-tailed pitviper in South Amer­ica that might be con­fused with B. bi­lin­eata is Both­riechis schlegelii, which has white or yel­low lines. How­ever, sym­pa­try be­tween Both­ri­op­sis bi­lin­eata and Both­riechis schlegelii has not been con­firmed. In Ecuador, Peru, and Bo­livia, there are four other green pitvipers. These in­clude Both­ri­op­sis pul­chra, B. pul­chra, B. pe­ru­viana, and B. oligolep­sis. All of these species lack the par­aven­tral stripes found in B. bi­lin­eata. (Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Mon­teiro, et al., 2006; Val­dujo, et al., 2002)

• Other Physical Features
• heterothermic
• venomous

• Sexual Dimorphism
• female larger

• Range length

  57.3 to 123 cm

  22.56 to 48.43 in

• Average length

  <70cm cm

  in

De­vel­op­ment

Both­ri­op­sis bi­lin­eata is ovo­vi­vip­a­rous, mean­ing that the eggs de­velop in­ter­nally, with the mother giv­ing birth to live young. Neonates are ven­omous upon birth and are known to be more ag­gres­sive at times than the adults. After birth, young feed upon frogs, lizards, and other rel­a­tively small prey. In­di­vid­ual size de­pends greatly on food avail­abil­ity. Adult fe­males are typ­i­cally larger than adult males. (Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Tra­vers, 1999)

Re­pro­duc­tion

There is no in­for­ma­tion avail­able re­gard­ing the mat­ing sys­tem of Both­ri­op­sis bi­lin­eata. How­ever, a study of Both­ri­op­sis tae­ni­ata at the Dal­las Zoo found that, dur­ing mat­ing, males po­si­tion them­selves on one side of the fe­male, while mov­ing across her dor­sum. While mov­ing, the male makes very jerky mo­tions and a hemipe­nis into the fe­male’s cloaca. The male flicks his tongue ex­tremely fast, ap­prox­i­mately 43 to 71 times a minute. Dur­ing this study, fe­males gave birth in June, July, and Oc­to­ber, with clutches rang­ing in size from 7 to 12 off­spring. In many pitvipers, male-male com­pe­ti­tion, known as "the dance of the adders", takes places dur­ing the mat­ing sea­son and is mainly pre­formed to guard ac­cess to mates. Some re­ports sug­gest that this be­hav­ior may also be used to com­pete for ter­ri­to­ries. Fight­ing be­tween males is done by hold­ing the face and fore­body erect and wrap­ping their bod­ies around one an­other as they at­tempt to force one an­other to the ground. Com­pet­i­tive bouts be­tween males can take hours and usu­ally ends with the win­ner gain­ing ac­cess a nearby fe­male for mat­ing. (Al­me­dia-San­tos and Sa­lo­mao, 2002; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Tra­vers, 1999)

Both­ri­op­sis bi­lin­eata is ovo­vi­vip­a­rous, mean­ing that the eggs de­velop in­ter­nally, with the mother giv­ing birth to live young. Clutch size ranges from 6 to 16 young. Neonates range in length from 20 to 26 cm and range in mass from 7 to 11 g, with an av­er­age of 10 g. Al­though lit­tle in­for­ma­tion is known con­cern­ing the re­pro­duc­tive be­hav­ior of Both­ri­op­sis bi­lin­eata, re­pro­duc­tive be­hav­ior of north­ern tem­per­ate pitvipers is thought to be very sim­i­lar. Re­pro­duc­tive cycle be­gins with sper­mato­ge­n­e­sis and vitel­lo­ge­n­e­sis. Vitel­lo­ge­n­e­sis in fe­males usu­ally oc­curs dur­ing late sum­mer or fall with the de­vel­op­ment of fol­li­cles paus­ing dur­ing win­ter and re­sum­ing dur­ing spring. Courtship and mat­ing gen­er­ally oc­curs dur­ing late sum­mer to win­ter, from April to Oc­to­ber. Long-term sperm stor­age may be used dur­ing the win­ter, from July to Sep­tem­ber, and is es­sen­tial in many pitvipers. De­lay­ing fer­til­iza­tion makes it pos­si­ble for birthing to occur dur­ing a fa­vor­able time of year and likely in­creases off­spring sur­vival. Dur­ing spring, ovu­la­tion, fer­til­iza­tion and em­bryo­ge­n­e­sis take place. Birth most likely oc­curs dur­ing the rainy sea­son of sum­mer, which is usu­ally in March. How­ever, this cycle likely varies in re­la­tion to weather, food avail­abil­ity and by species. (Al­me­dia-San­tos and Sa­lo­mao, 2002; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Tra­vers, 1999)

• Key Reproductive Features
• seasonal breeding
• sexual
• fertilization
• ovoviviparous
• sperm-storing
• delayed fertilization

• Range number of offspring

  4 to 16

• Average number of offspring

  9

Both­ri­op­sis bi­lin­eata fe­males store sperm until the op­ti­mal time to fer­til­ize the eggs. Once the eggs are fer­til­ized, the mother car­ries the em­bryos until the eggs are ready to hatch, which oc­curs in­ter­nally. For all pitvipers, young ven­omous upon birth and are able to hunt. Some moth­ers stay with the young for 7 to 10 days. How­ever, young are typ­i­cally in­de­pen­dent upon birth. (Al­me­dia-San­tos and Sa­lo­mao, 2002; Tra­vers, 1999)

• Parental Investment
• pre-hatching/birth
  • provisioning
    • female

Lifes­pan/Longevity

There is no in­for­ma­tion on the av­er­age lifes­pan of Both­ri­op­sis bi­lin­eata. In gen­eral, es­ti­mated lifes­pan for pitvipers ranges from 10 to 25 years, with vari­a­tions most likely due to cap­tiv­ity. One ac­count de­scribes a B. tae­ni­ata that lived in the Dal­las Zoo for 13 years, after being re­ceived by the zoo as an adult. (Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Tra­vers, 1999)

Be­hav­ior

Both­ri­op­sis bi­lin­eata is noc­tur­nal and spends most of the day in thick fo­liage or at the base of palm trees, gen­er­ally 1 m or higher above the ground. It uses its pre­hen­sile tail to an­chor it­self on to trees and shrub­bery. To con­serve en­ergy, B. bi­lin­eata tends to hide in shaded areas and moves very lit­tle through­out the day. Both­ri­op­sis bi­lin­eata is an am­bush preda­tor. Like other pitvipers, B. bi­lin­eata has pits re­sem­bling nos­trils that sense var­i­ous wave­lengths of in­frared heat. Be­cause tem­per­a­tures at night are cooler, a greater heat sig­na­ture is gen­er­ated by po­ten­tial prey. The pits are lo­cated on both sides of the head, cre­at­ing a stereo ef­fect that al­lows B. bi­lin­eata to de­ter­mine the di­rec­tion and dis­tance of prey. Ex­per­i­ments con­ducted on pitvipers have shown that when de­prived of sight and smell, they can strike ac­cu­rately on tar­gets 0.2 C greater than sur­round­ing am­bi­ent tem­per­a­ture. ("Ven­omous An­i­mals and Plants", 2008; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Tra­vers, 1999)

• Key Behaviors
• arboreal
• scansorial
• nocturnal
• sedentary

Home Range

There is no in­for­ma­tion avail­able re­gard­ing the av­er­age home range size of Both­ri­op­sis bi­lin­eata.

Com­mu­ni­ca­tion and Per­cep­tion

Both­ri­op­sis bi­lin­eata, like other pitvipers, has heat-sens­ing pits lo­cated be­tween the eyes and nos­trils, on both sides of the head. Within these pits are nu­mer­ous heat-sen­si­tive nerves that are cov­ered by thin mem­bra­nous tis­sue. The pits are highly vas­cu­lar­ized, which helps main­tain a con­stant tem­per­a­ture, thereby in­creas­ing sen­si­tiv­ity to changes in am­bi­ent tem­per­a­ture. In ad­di­tion to heat-sens­ing pits, B. bi­lin­eata also has well-de­vel­oped binoc­u­lar vi­sion re­sult­ing from its ver­ti­cal slits. This trait, com­mon to all pitvipers, in­creases depth and vi­sual per­cep­tion. Like all snakes, Both­ri­op­sis bi­lin­eata has an adept ol­fac­tory per­cep­tion. ("Ven­omous An­i­mals and Plants", 2008; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004)

Other than those that occur dur­ing mat­ing sea­son, lit­tle is known about in­traspe­cific in­ter­ac­tions in Both­ri­op­sis bi­lin­eata. Dur­ing mat­ing sea­son, male-male com­pe­ti­tion takes place. Dur­ing these com­pet­i­tive in­ter­ac­tions, two males be­come in­ter­twined in an at­tempt to force one an­other to the ground. The win­ner gains ac­cess to mates and ter­ri­tory. Al­though they lack ears, snakes are highly sen­si­tive to vi­bra­tions. ("Ven­omous An­i­mals and Plants", 2008; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004)

• Communication Channels
• visual
• tactile

• Other Communication Modes
• vibrations

• Perception Channels
• visual
• infrared/heat
• vibrations
• chemical

Food Habits

Two-striped for­est pitvipers are noc­tur­nal preda­tors. They rest in trees and shrubs 3 to 4 feet above the ground and use their heat-sens­ing pits to gen­er­ate a ther­mal pic­ture of the sur­round­ing en­vi­ron­ment and po­ten­tial prey. Ev­i­dence sug­gests that they oc­ca­sion­ally use their tails as a lure to at­tract prey. These vipers prey mainly on frogs, but also reg­u­larly eat small birds. Re­cently, stom­ach con­tent analy­sis has re­vealed that two-striped for­est pitvipers also feed on a va­ri­ety of lizards and small mam­mals, in­clud­ing mice and rab­bits. ("Ven­omous An­i­mals and Plants", 2008; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Ro­drigo C. G. de Souza, M.D. and Fun­daçã o Hos­pi­ta­lar Itacare, 2007)

• Primary Diet
• carnivore
  • eats terrestrial vertebrates

• Animal Foods
• birds
• mammals
• amphibians
• reptiles

Pre­da­tion

Neotrop­i­cal birds of prey tend to feed on ven­omous snakes, but be­cause two-striped for­est pitvipers are noc­tur­nal and well-cam­ou­flaged, lit­tle is known about their preda­tors. Birds of prey known to feed on ven­omous snakes in the Ama­zon in­clude laugh­ing fal­cons, crane hawks, road­side hawks, and swal­low-tailed kites. (Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; "De­for­esta­tion in the Ama­zon", 2010)

• Anti-predator Adaptations
• cryptic

Ecosys­tem Roles

Both­ri­op­sis bi­lin­eata are preda­tors of many species of small birds, frogs, and lizards in their ecosys­tem. They are highly ven­omous and are prob­a­bly avoided by most species through­out their ge­o­graphic range. Par­a­sites of this species are un­known. (Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

In the past, the venom of Both­ri­op­sis bi­lin­eata has been the sub­ject of re­search for its an­ti­co­ag­u­la­tion prop­er­ties; how­ever, lo­cat­ing this species is re­port­edly very chal­leng­ing. There­fore, not a great deal of re­search has been con­ducted on this species. ("Ven­omous An­i­mals and Plants", 2008; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004)

• Positive Impacts
• research and education

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

Both­ri­op­sis bi­lin­eata is po­ten­tially dan­ger­ous, as a sin­gle strike from this snake re­leases ex­tremely toxic venom. Their venom is con­tains pro-co­ag­u­lant and an­ti­co­ag­u­lant agents and their bite can re­sult in se­vere he­m­or­rhag­ing. Both­ri­op­sis bi­lin­eata has been re­ported to be the sec­ond most dan­ger­ous snake in the Ama­zon, be­hind only Both­rops atrox. Nu­mer­ous ac­counts of bites have been doc­u­mented, some re­sult­ing in death. In stud­ies of snake bite cases near Co­lum­bia, about 15% of bites were from B. bi­lin­eata. Bleed­ing from the gums, site of bite, and ori­fices often occur after a bite. Other re­lated symp­toms in­clude he­mateme­sis, hema­turia, loss of con­scious­ness, ery­thema, headaches, pain at en­ven­o­ma­tion site, tis­sue necro­sis, and edema. Both­ri­op­sis bi­lin­eata is not con­sid­ered an ag­gres­sive species, but has been known to strike when dis­turbed. Be­cause this is an ar­bo­real species, most bites re­ported are to the hands, arms, and face. ("Ven­omous An­i­mals and Plants", 2008; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; O'Shea, 2005; Small­i­gan, et al., 2004; Tra­vers, 1999)

• Negative Impacts
• injures humans
  • bites or stings
  • venomous

Con­ser­va­tion Sta­tus

Both­ri­op­sis bi­lin­eata has not been eval­u­ated by the IUCN and is not cur­rently listed on any threat­ened species lists. The great­est threat to this species is hu­mans. De­for­esta­tion has been linked to pop­u­la­tion de­clines, and from 1988 to 2010, about 385,000 km^2 of pri­mary habi­tat in the Ama­zon has been de­stroyed. While it is know that this species is dis­trib­uted through­out low­land rain forests in the Ama­zon, Bo­livia, Peru, Ecuador, Brazil, Venezuela, and the Guianas (el­e­va­tions below 1,000 m, usu­ally near wa­ter­ways), lit­tle in­for­ma­tion is avail­able about cur­rent pop­u­la­tion sizes. Its noc­tur­nal ac­tiv­ity and col­oration make its num­bers dif­fi­cult to es­ti­mate. Be­cause it is highly ven­omous, this species is often killed when en­coun­tered by human.

• IUCN Red List

  No special status

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Other Com­ments

The name Both­ri­op­sis bi­lin­eata comes from the Greek words "both­ros" mean­ing "pit" and "-op­sis" mean­ing "face", in ref­er­ence to their fa­cial pit or­gans. The ep­i­thet "bi­lin­eata" is de­rived from Latin. "Bi-" is a pre­fix for "two" and "lin­ea­tus" for "lined or marked with lines". This per­tains to their ven­tro­lat­eral yel­low stripes. Other com­mon names noted for the pitviper are green Tommy goffi, Cobra pa­pa­gaio, lora, orito, and loro machaco. ("Ven­omous An­i­mals and Plants", 2008; Camp­bell and Lamar, 1989; Camp­bell and Lamar, 2004; Tra­vers, 1999)

Con­trib­u­tors

Evin Guil­liams (au­thor), Rad­ford Uni­ver­sity, Brian In­gram (au­thor), Rad­ford Uni­ver­sity, Chris­tine Small (ed­i­tor), Rad­ford Uni­ver­sity, John Berini (ed­i­tor), An­i­mal Di­ver­sity Web Staff.

Ref­er­ences

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Bar­rio-Amorós, César Luis, 2010. A new Ceuthoman­tis (Anura: Ter­rarana: Ceuthoman­ti­dae) from Saris­ariñama Tepui, South­ern Venezuela. Her­peto­log­ica, 66(2): 172-181.

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