''Bothriechis schlegelii'', known commonly as the eyelash viper, is a

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 appropriat ...

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 ...

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. . crotaline snakes (from grc, κρόταλον ''krotalon'' castanet), or pit adders, are a subfa ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Viperidae 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 th ...

. The species is native to Central and South America. Small and

arboreal Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. The habitats pose nu ...

, this species is characterized by a wide array of color variations, as well as the superciliary scales above the eyes. It is the most common of the green palm-pitvipers (genus ''Bothriechis''), and is often present in zoological exhibits. The specific name ''schlegelii'' honors

Hermann Schlegel Hermann Schlegel (10 June 1804 – 17 January 1884) was a German ornithologist, herpetologist and ichthyologist. Early life and education Schlegel was born at Altenburg, the son of a brassfounder. His father collected butterflies, which stimulate ...

, who was a German

ornithologist Ornithology is a branch of zoology that concerns the "methodological study and consequent knowledge of birds with all that relates to them." Several aspects of ornithology differ from related disciplines, due partly to the high visibility and th ...

and

herpetologist Herpetology (from Greek ἑρπετόν ''herpetón'', meaning "reptile" or "creeping animal") is the branch of zoology concerned with the study of amphibians (including frogs, toads, salamanders, newts, and caecilians ( gymnophiona)) and rep ...

. For other common names see

below Below may refer to: *Earth *Ground (disambiguation) *Soil *Floor *Bottom (disambiguation) *Less than *Temperatures below freezing *Hell or underworld People with the surname *Ernst von Below (1863–1955), German World War I general *Fred Below ( ...

. No subspecies are currently recognized as being valid.

Description

The eyelash viper is a relatively small species of pitviper, with adults ranging from long, and females being longer and more variable in size than males, which can grow to long. It has a wide, triangular-shaped head, and eyes with vertical

pupil The pupil is a black hole located in the center of the Iris (anatomy), iris of the Human eye, eye that allows light to strike the retina.Cassin, B. and Solomon, S. (1990) ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing ...

s. Like all pit vipers, it is

solenoglyphous A snake skeleton consists primarily of the skull, vertebrae, and ribs, with only vestigial remnants of the limbs. Skull The skull of a snake is a very complex structure, with numerous joints to allow the snake to swallow prey far larger than it ...

, having large,

hypodermic needle A hypodermic needle (from Greek ὑπο- (''hypo-'' = under), and δέρμα (''derma'' = skin)), one of a category of medical tools which enter the skin, called sharps, is a very thin, hollow tube with one sharp tip. It is commonly used ...

-like fangs in the front of the upper jaw that fold back when not in use, and has heat sensitive organs, or pits, located on either side of the head between the eye and nostril. Its most distinguishing feature, and origin of its common name, is the set of modified scales above the eyes that look much like

eyelash An eyelash (also called lash) (Latin: ''Cilia'') is one of the hairs that grows at the edge of the eyelids. It grows in one layer on the edge of the upper and lower eyelids. Eyelashes protect the eye from debris, dust, and small particles and p ...

es. The eyelashes are thought to aid in

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 b ...

, breaking up the snake's outline among the foliage where it hides. The eyelash viper occurs in a wide range of colors, including red, yellow, brown, green, even pink, as well as various combinations thereof. It often has black or brown speckling on the base color. No external features distinguish the two sexes.

Common names

Common names of ''B. schlegelii'' include the eyelash viper, eyelash pit viper, eyelash palm viper, eyelash palm-pitviper, Schlegel's viper, Schlegel's pit viper, Parker HW, Grandison AGC (1977). ''Snakes -- A Natural History''. Second Edition. British Museum (Natural History) and Cornell University Press. 108 pp. 16 plates. LCCCN 76-54625. (cloth), (paper), Schlegel's palm viper,Brown JH (1973). ''Toxicology and Pharmacology of Venoms from Poisonous Snakes''. Springfield, Illinois: Charles C. Thomas. 184 pp. LCCCN 73-229. . eyelash snake, eyelash lancehead, eyelash mountain viper, and horned palm viper. In Spanish, the primary language of countries comprising its distribution, common names include ''bocaracá'', ''oropel'' (golden morph), ''víbora bocaracá'', ''toboba pestañas'', ''víbora de pestañas'' (eyelash viper), and ''serpiente loro'' (parrot snake).

Geographic range

The geographic range of ''B. schlegelii'' extends from southern Mexico (northern

Chiapas Chiapas (; Tzotzil and Tzeltal: ''Chyapas'' ), officially the Free and Sovereign State of Chiapas ( es, Estado Libre y Soberano de Chiapas), is one of the states that make up the 32 federal entities of Mexico. It comprises 124 municipalities ...

), southeastward on the Atlantic plains and lowlands through Central America to northern South America in Colombia and Venezuela. It is also found on the Pacific versant and lowlands in parts of Costa Rica, Panama, Colombia, Ecuador and Peru. It occurs in

mesic forest In ecology, a mesic habitat is a type of habitat with a moderate or well-balanced supply of moisture, e.g., a mesic forest, a temperate hardwood forest, or dry-mesic prairie. Mesic habitats transition to xeric shrublands in a non-linear fashion, ...

at elevations almost from sea level to altitude. The type locality is “Popayan” ( Popayán, Colombia).

Habitat

''B. schlegelii'' prefers lower altitude, humid,

tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

areas with dense foliage, generally not far from a permanent water source. One study noted the preference of ''B. schlegelii'' for deep, shady ravines.

Behavior

Like other ''Bothriechis'' members, ''B. schlegelii'' is

and has a strong

prehensile tail A prehensile tail is the tail of an animal that has adapted to grasp or hold objects. Fully prehensile tails can be used to hold and manipulate objects, and in particular to aid arboreal creatures in finding and eating food in the trees. If the t ...

. It is largely

nocturnal Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite. Nocturnal creatures generally have highly developed sens ...

, consuming small rodents, frogs, lizards and small birds. It is not known to be an aggressive snake, but will not hesitate to strike if harassed. A typical ambush predator, it waits patiently for unsuspecting prey to wander by. Sometimes, it is known to select a specific ambush site and return to it every year in time for the spring migration of birds. Studies have indicated that ''B. schlegeli'' learns to improve strike accuracy over time.
/sup> Sometimes ''B. schlegelii'' (especially juveniles) will employ what is known as “ Caudal (anatomical term), caudal luring”, wiggling the tail in worm-like motions to encourage potential prey to move within striking range. There is a myth among villagers in some small areas of South America that the eyelash viper will wink, flashing its "eyelashes" at its victim, following a venomous strike. Snakes are not physiologically capable of such behavior, as they have no eyelids and can not close their eyes. Goin CJ, Goin OB, Zug GR (1978). ''Introduction to Herpetology, Third Edition''. San Francisco: W.H. Freeman and Company. xi + 378 pp. . ("Snakes ... glassy, unwinking glare", p. 53).

Reproduction

The eyelash viper reaches sexual maturity at around two years of age, and the ovoviviparous species reproduces throughout the year in warm environments. Females carry eggs for around six months before they hatch internally, where the young complete their development. Pregnant females have enlarged lower abdomens, and may stop eating in later stages of pregnancy. In a typical brood they give birth to 2–20 live young, which are in length and appear physically similar to adults. Males engage in a sometimes hours-long courtship ritual called a "dance of the adders", in which two males posture and intimidate one another in an upright, "cobra-like" stance until one is pushed away or falls to the ground. They are

polygynous Polygyny (; from Neoclassical Greek πολυγυνία (); ) is the most common and accepted form of polygamy around the world, entailing the marriage of a man with several women. Incidence Polygyny is more widespread in Africa than in any ...

, and usually mate at night.

Captivity

Despite the inherent danger of its venom, ''B. schlegelii'' is frequently available in the exotic animal trade, and is well represented in

zoo A zoo (short for zoological garden; also called an animal park or menagerie) is a facility in which animals are kept within enclosures for public exhibition and often bred for conservation purposes. The term ''zoological garden'' refers to z ...

s worldwide. It is frequently captive bred for color and pattern. Exporting from the wild is not as common as it once was, but is not unknown. In general they make hardy captives, readily feeding on provided mice.

Taxonomy

Some authorities also recognize a

montane Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial ...

form that is treated either as a subspecies (''B. s. supraciliaris'') or as a species ('' B. supraciliaris''). Found in the province of San José in

Costa Rica Costa Rica (, ; ; literally "Rich Coast"), officially the Republic of Costa Rica ( es, República de Costa Rica), is a country in the Central American region of North America, bordered by Nicaragua to the north, the Caribbean Sea to the no ...

, it was sometimes referred to as the ''eyelash mountain viper'', while more recent publications recognizing the species designation refer to it as the blotched palm-pitviper.

Conservation

Eyelash vipers have not been evaluated by the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biolo ...

, and were removed from

CITES CITES (shorter name for the Convention on International Trade in Endangered Species of Wild Fauna and Flora, also known as the Washington Convention) is a multilateral treaty to protect endangered plants and animals from the threats of intern ...

Appendix III in 2002. While not listed as threatened, they could be at risk of habitat loss from increased deforestation for timber, agriculture, and urbanization.

Gallery

File:Bothriechis schlegelii (La Selva, Sarapiqui, CR).jpg, Yellow individual in La Selva Biological Station File:Eyelash viper (Bothriechis schlegelii) (9344764791).jpg, White individual in

Cahuita National Park Cahuita National Park is a terrestrial and marine national park in the Caribbean La Amistad Conservation Area of Costa Rica located on the southern Caribbean coast in Limón Province, connected to the town of Cahuita. It protects beaches and l ...

File:EyelashViper2010.jpg, Facial features File:Eyelash Viper (Bothriechis schlegelii) female threat display (captive specimen) (14813138374).jpg, Threat behavior File:Los ofidios venenosos del Cauca (6260742560).jpg, Illustration

References

External links

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Eyelash viper
a
WhoZoo
Accessed 27 November 2008.
Eyelash pit viper
Accessed 27 November 2008.