Bothriechis schlegelii

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 pupils. Like all pit vipers, it is solenoglyphous, having large, hypodermic needle-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 eyelashes. The eyelashes are thought to aid in camouflage, breaking up the snake's outline among the foliage where it hides. The eyelash viper occurs in a wide range of colors. 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 palm viper, eyelash snake, eyelash mountain viper, In Spanish, the primary language of countries comprising its distribution, common names include bocaracá, oropel (golden morph), víbora de pestañas (eyelash viper), and serpiente loro (parrot snake). ==Geographic range==

Previously thought to range from southern Mexico to northwestern South America, a systematic revision of the species in 2024 caused many of the populations in its purported range to become their own separate species. Although these species are very closely related, this restricts the range of B. schlegelii sensu stricto to Colombia, in primarily highland regions. ==Behavior==

Like other Bothriechis species, B. schlegelii is adapted to a nearly completely arboreal lifestyle, possessing a strong, prehensile tail with which it secures itself around tree limbs, often coiled into a tight bundle during the day, as the species is primarily nocturnal. After dark, the eyelash viper awakens and awaits the presence of small, tree-dwelling animals that may cross its path, including mammals (rodents, bats, mouse opossums), amphibians (cloud forest landfrogs, fleshbelly frogs, tree frogs), birds (hummingbirds) or lizards (anoles, geckos, juvenile iguanas, whiptails), as well as occasionally fish. In typical ambush-predator fashion, B. schlegelii waits patiently for potential, unsuspecting prey to wander by. In some cases, individuals have been known to select specific ambush sites, returning each year in-time for the spring bird migration. Studies have indicated that individuals of B. schlegeli perfect their own strike accuracy with practice, over time. Sometimes, B. schlegelii (especially juveniles) will employ what is known as "caudal luring", wriggling their tail in a "worm"-like fashion to entice potential prey, such as hungry frogs or lizards, to move within striking-range. The eyelash viper is not known to be an aggressive snake towards humans, and is likely to be avoidant of creatures larger than itself, but will not hesitate to strike if repeatedly harassed. Certain local mythologies and folktales (notably in remote areas of northern South America) describe how after one is bitten by an eyelash viper, the snake will "wink" its "eyelashes" at the victim. In reality, no snake is physiologically capable of such behaviors as they possess no true eyelids and cannot close their eyes; however, most reptiles possess a thin, membranous "eyelid" as a retractable "shield" for their eyes, mainly when resting. == Venom ==

Composition The most important components of B. schlegeli venom are phospholipase A2 related to the production of edema, tissue damage and myotoxicity, metalloproteases with dermonecrosis, L-amino acid oxidases with tissue damage, serine proteases with tissue damage and hemorrhagic diathesis, lectin type C with tissue damage and hemorrhagic diathesis, disintegrins with detachment of cells from their extracellular matrix leading to blisters and platelet function impairment, bradykinin-potentiating peptides with hypotension, enzymes that degrade fibrinogen, plasminogen activators, prothrombin activators, factor V activators, factor X activators, and anticoagulant activities (including inhibitors of prothrombinase complex formation, inhibitors of thrombin, phospholipases, and protein C activators). Clinical management Snakebites inflicted by B. schlegelii in humans are characterized by pain, edema, and ecchymosis at the site of the bite, rarely with blisters, local necrosis, or defibrination. Some investigations using venom samples of B. schlegelii from the northern region of Colombia have reported a typical bothropic envenomation characterized by pain, rapid local tissue damage, edema and inflammatory reactions at the site of the bite, followed by systemic alterations such as coagulopathy and acute renal failure. ==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, and usually mate at night. ==Captivity==

Despite its venom, B. schlegelii is frequently available in the exotic animal trade, and is well represented in zoos 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 form that is treated either as a subspecies (B. s. supraciliaris) or as a species (B. supraciliaris). it was sometimes referred to as the eyelash mountain viper, specimen (juvenile)Although considered to likely contain multiple species for some time, the great variety of colour patterns in the species has previously made this difficult to verify. ==Conservation==

Eyelash vipers were evaluated for the IUCN Red List as being of least concern for extinction in 2013, having been removed from CITES Appendix III in 2002. While not listed as threatened, they are at risk of habitat loss from increased deforestation for timber, agriculture, and urbanization. However, the species is adaptable and can live in secondary forests as well as coffee and banana plantations. ==Gallery==

File:Los ofidios venenosos del Cauca (6260742560).jpg|Illustration File:Eyelash Viper (Bothriechis schlegelii) female threat display (captive specimen) (14813138374).jpg|Eyelash Viper (Bothriechis schlegelii) female threat display (captive specimen) File:Bothriechis schlegelii 28759363.jpg File:Bothriechis schlegelii 80081508.jpg File:Bothriechis schlegelii 98839418.jpg ==References==