Common names: two-striped forest-pitviper, parrotsnake, Amazonian palm viper.

Bothriopsis bilineata is a venomous

Venomous snake

"Poisonous snake" redirects here. For true poisonous snakes, see Rhabdophis.Venomous snakes are snakes which have venom glands and specialized teeth for the injection of venom...

 pitviper

Crotalinae

The Crotalinae, commonly known as "pit vipers" or crotaline snakes, are a subfamily of venomous vipers found in Asia and the Americas. They are distinguished by the presence of a heat-sensing pit organ located between the eye and the nostril on either side of the head...

 species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 found in the Amazon

Amazon Basin

The Amazon Basin is the part of South America drained by the Amazon River and its tributaries that drains an area of about , or roughly 40 percent of South America. The basin is located in the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, and Venezuela...

 region of South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

. A pale green arboreal species that may reach a meter in length, it is an important cause of snakebite throughout the entire Amazon region. Two subspecies

Subspecies

Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 are currently recognized, including the nominate subspecies described here.

Description

Adults usually do not grow to more than 70 cm in length, although some may reach 100 cm. The maximum reported size is 123 cm. The body is relatively slender with a prehensile tail.

The scalation includes 23-35 dorsal scales

Dorsal scales

In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales.When counting dorsal scales, numbers are often given for three points along the body, for example 19:21:17...

 ant midbody, 190-218/192-220 ventral scales

Ventral scales

In snakes, the ventral scales 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 contacts the paraventral row of dorsal scales on either side...

 in males/females and 65-76/55-73 mostly divided subcaudal scales

Subcaudal scales

In snakes, the subcaudal scales are the enlarged plates on the underside of the tail. These scales may be either single or divided and are preceded by the anal scale....

 in males/females. On the head there are 5-9 keeled

Keeled scales

Keeled scales refer to reptile scales that, rather than being smooth, have a ridge down the center that may or may not extend to the tip of the scale, making them rough to the touch...

 intersupraoculars, 8-12 sublabial scales

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 scale . The term labial originates from Labium , which refers to any lip-like structure...

 and 7-9 supralabial scales

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 scale . The term labial originates from Labium , which refers to any lip-like structure...

. Of the latter, the second is usually fused with the prelacunal to form a lacunolabial, although partial or complete sutures may exist to separate these scales.

The color pattern consists of a pale green ground color that is overlaid dorsally with either a peppering of black spots, or a series of tan or reddish brown spots that are usually paired. The ventrals are bordered by a creamy yellow line running down the length of the body, while the belly itself is yellow and bordered with a tinge of green. The latter part of the tail is pink and bordered with yellow. The head is either green with a scattering of small black spots, or green with isolated tan or reddish brown spots that are bordered in black. The iris is pale green while the labials are yellow green, often with black spots.

The nominate subspecies, B. b. bilineata, has vertical dark stripes on the supralabial scales and a dorsal pattern of reddish brown spots with black flecks.

Geographic range

Found in the Amazon

Amazon Basin

The Amazon Basin is the part of South America drained by the Amazon River and its tributaries that drains an area of about , or roughly 40 percent of South America. The basin is located in the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, and Venezuela...

 region of South America

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

: Colombia

Colombia

Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...

, Venezuela

Venezuela

Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...

, Guyana

Guyana

Guyana , officially the Co-operative Republic of Guyana, previously the colony of British Guiana, is a sovereign state on the northern coast of South America that is culturally part of the Anglophone Caribbean. Guyana was a former colony of the Dutch and of the British...

, Surinam, French Guiana

French Guiana

French Guiana is an overseas region of France, consisting of a single overseas department located on the northern Atlantic coast of South America. It has borders with two nations, Brazil to the east and south, and Suriname to the west...

, Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

, Ecuador

Ecuador

Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border...

, Peru

Peru

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

 and Bolivia

Bolivia

Bolivia officially known as Plurinational State of Bolivia , is a landlocked country in central South America. It is the poorest country in South America...

. An isolated population is known from the Atlantic versant of southeastern Brazil. The type locality given is "Brasilien."

Habitat

Lowland rain forest, in shrubbery, palms and trees, especially in the vicinity of water. Soini (1974) states that it is almost always found in bushes and trees along streams or along the edges for forest clearings. Mostly associated with primary forest, although is also been found in older secondary forest

Secondary forest

A secondary forest is a forest or woodland area which has re-grown after a major disturbance such as fire, insect infestation, timber harvest or windthrow, until a long enough period has passed so that the effects of the disturbance are no longer evident...

 near primary forest.

Behavior

Nocturnal, this species spends the day hidden in thick foliage, tree hollows or at the base of palm fronds, and always in places where it can anchor itself with its prehensile tail. They tend to rely on ambush instead of actively hunting for prey.

Feeding

The diet consis of small mammals, such as mouse opossums (Marmosa

Marmosa

The nine species in the genus Marmosa are relatively small Neotropic members of the order Didelphimorphia. This genus is one of four that are known as mouse opossums. The others are Micoureus , Thylamys and Tlacuatzin, the grayish mouse opossum...

), mice, birds, lizards and frogs. Juveniles tend to remain closer to the ground to feed on small frogs and lizards.

Venom

This species is an important cause of snakebite throughout the entire amazon region. Due to its arboreal nature, most bites are to the upper body, including hands, arms and face.

Clinical features include bruising, profound coagulopathy

Coagulopathy

Coagulopathy is a condition in which the blood’s ability to clot is impaired. This condition can cause prolonged or excessive bleeding, which may occur spontaneously or following an injury or medical and dental procedures.The normal clotting process depends on the interplay of various proteins in...

 and spontaneous bleeding. Symptoms reported from various case histories include local pain, swelling, bruising, bleeding of the gums, loss of consciousness, hematemesis

Hematemesis

Hematemesis or haematemesis is the vomiting of blood. The source is generally the upper gastrointestinal tract. Patients can easily confuse it with hemoptysis , although the latter is more common.-Signs:...

, hematuria

Hematuria

In medicine, hematuria, or haematuria, is the presence of red blood cells in the urine. It may be idiopathic and/or benign, or it can be a sign that there is a kidney stone or a tumor in the urinary tract , ranging from trivial to lethal...

, fever, erythema

Erythema

Erythema is redness of the skin, caused by hyperemia of the capillaries in the lower layers of the skin. It occurs with any skin injury, infection, or inflammation...

, bleeding from the fang punctures, shock, bleeding from the mouth, nose and eyes, nausea, and incoagulable blood. At least one death has been reported.

Subspecies

Subspecies	Taxon author	Common name	Geographic range
B. b. bilineata	(Wied-Neuwied Prince Maximilian of Wied-Neuwied Prince Alexander Philipp Maximilian zu Wied-Neuwied was a German explorer, ethnologist and naturalist.... , 1821)	Amazonian palm viper	South America South America South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...  in the equatorial forests of Venezuela Venezuela Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south... , Guyana Guyana Guyana , officially the Co-operative Republic of Guyana, previously the colony of British Guiana, is a sovereign state on the northern coast of South America that is culturally part of the Anglophone Caribbean. Guyana was a former colony of the Dutch and of the British... , Suriname Suriname Suriname , officially the Republic of Suriname , is a country in northern South America. It borders French Guiana to the east, Guyana to the west, Brazil to the south, and on the north by the Atlantic Ocean. Suriname was a former colony of the British and of the Dutch, and was previously known as... , French Guiana French Guiana French Guiana is an overseas region of France, consisting of a single overseas department located on the northern Atlantic coast of South America. It has borders with two nations, Brazil to the east and south, and Suriname to the west...  and Brazil Brazil Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people... , including the Atlantic Forest.
B. b. smaragdinus Bothriopsis bilineata smaragdinus Bothriopsis bilineata smaragdinus is a venomous pitviper subspecies found in the northern and western Amazon region of South America.-Description:Same as for B. b...	(Hoge, 1966)	Loro machaco (Peru Peru Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean.... )	South America in the Amazon Amazon Basin The Amazon Basin is the part of South America drained by the Amazon River and its tributaries that drains an area of about , or roughly 40 percent of South America. The basin is located in the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, and Venezuela...  regions of Colombia Colombia Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the... , southern Venezuela, northern and western Brazil, Ecuador Ecuador Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border... , Peru Peru Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....  and Bolivia Bolivia Bolivia officially known as Plurinational State of Bolivia , is a landlocked country in central South America. It is the poorest country in South America... .

If these subspecies are eventually proved to be monophyletic

Clade

A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

, then this will suggest that the Amazon Rainforest

Amazon Rainforest

The Amazon Rainforest , also known in English as Amazonia or the Amazon Jungle, is a moist broadleaf forest that covers most of the Amazon Basin of South America...

 split into eastern and western parts before the eastern part split from the more southern Atlantic Forest.