''Atheris desaixi'', commonly known as the Mount Kenya bush viper, Spawls S, Branch B (1995). ''The Dangerous Snakes of Africa''. Dubai: Ralph Curtis Books / Oriental Press. 192 pp. . Mallow D, Ludwig D, Nilson G (2003). ''True Vipers: Natural History and Toxinology of Old World Vipers''. Malabar, Florida: Krieger Publishing Company. 359 pp. . Ashe's bush viper, or Desaix's bush viper, is a

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 ...

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), ...

viper Vipers are snakes in the family Viperidae, found in most parts of the world, except for Antarctica, Australia, Hawaii, Madagascar, New Zealand, Ireland, and various other isolated islands. They are venomous and have long (relative to non-vipe ...

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to Kenya, where only two isolated populations are known. It is known for its striking black and yellow coloration. No

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

are currently recognized.

Etymology

This species, ''A. desaixi'', is named in honor of Frank DeSaix, an American

Peace Corps The Peace Corps is an Independent agency of the U.S. government, independent agency and program of the United States government that trains and deploys volunteers to communities in partner countries around the world. It was established in Marc ...

volunteer who collected the first specimen. Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . (''Atheris desaixi'', p. 70).

Description

Adults of ''A. desaixi'' average 40–60 cm (about 16-24 inches) in total length (including tail), with a maximum total length of . Newborns measure in total length. In Ashe's original 1968 description, adults were reported to grow to an average 49–68 cm (about 19-27 inches) total length, with a head and body length of and a tail length of . The eyes are set well forward in the head and are surrounded by 14–17 scales. Interorbital scales number 8–11. The eye is separated from the

nasal Nasal is an adjective referring to the nose, part of human or animal anatomy. It may also be shorthand for the following uses in combination: * With reference to the human nose: ** Nasal administration, a method of pharmaceutical drug delivery * ...

by two to three scales and from the

supralabials 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 ( ...

by two. Upper labials: 10–12. Sublabials: 11–14. 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 not as wide as it is long, while its upper margin is highest at the center. The rostral is also accompanied by an even number of suprarostrals. The superciliary scales above the eyes are not enlarged (as opposed to '' A. ceratophora''). The nasal scale is round and single, or partially divided. Midbody, the

dorsal scale 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 ...

rows number 24–31. The dorsal scales are short and heavily keeled. However, on the upper dorsals the keels terminate before the end of each scale. On the lower dorsals, the keels are serrated (like in '' Echis''). The

ventral scale 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 ...

count is 160–174. In females the subcaudals number 41–54. One male specimen had 53 subcaudals. The color pattern consists of a greenish-black to charcoal-black ground color, while each scale is tipped with yellow or yellowish-green, giving the animal a speckled appearance. Some scales have more of this color to them and form a series of loops along the sides of the body. These loops may fuse into zigzag patterns posteriorly, fading again on the tail. Anteriorly, the venter is yellow or yellowish, fading towards a purplish-black towards the rear and under the tail, except for the tip that is blotched with yellow. Juveniles are mainly yellow with a white tipped tail. This darkens as they grow until they reach the adult color phase at a total length of about .

Distribution and habitat

There are two isolated populations of ''A. desaixi'' in Kenya: one in the forests at Chuka, south-eastern

Mount Kenya Mount Kenya (Meru people, Meru: ''Kĩrĩmaara,'' Kikuyu people, Kikuyu: ''Kĩrĩnyaga'', Kamba language, Kamba: ''Ki nyaa'', Embu language, Embu: ''Kĩ nyaga'') is an extinct volcano in Kenya and the Highest mountain peaks of Africa, second-highe ...

, and the other near Igembe in the northern Nyambeni range. The type locality is listed as "near Chuka, Lat. 0° 20' S, Long. 37° 35' E, in rain forest at an altitude of c. ", Kenya. The original specimens, for which field notes were taken, were found in dense

rain forest Rainforests are forests characterized by a closed and continuous tree Canopy (biology), canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforests can be generally classified as tropi ...

at , collected in clearings and along pathways in the dense foliage about above the ground. The conditions were very humid and all specimens were collected within a radius. In this environment, their coloration offers them an excellent camouflage, making them very difficult to spot.

Behavior

Little is known of the behavior of ''A. desaixi''. It is obviously

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 (scansorial), but others are exclusively arboreal. The hab ...

, moving slowly and deliberately among the branches of its habitat as other ''Atheris'' species do, but it is unknown when daily peak activity occurs. In captivity, it is just as willing to accept food during the day as at night. When captured, it will strike readily and struggle vigorously in the hand. It may also perform a characteristic, stridulating threat display, in which counterlooped coils and the lower serrated, keeled scales are rubbed against one another to produce a loud hissing noise. However, captive specimens soon calm down and this behavior is lost.

Feeding

''A. desaixi'' is reported to be an opportunist, preying on

amphibian Amphibians are ectothermic, anamniote, anamniotic, tetrapod, four-limbed vertebrate animals that constitute the class (biology), class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all Tetrapod, tetrapods, but excl ...

rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...

s and small

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

Reproduction

A gravid female specimen of ''A. desaixi'' found in the Nyambeni range is reported to have given birth to 13 offspring in the month of August. Newborns measured in total length.

Interactions with humans

Conservation status

As of 2019, the species ''A. desaixi'' is listed as

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, inv ...

on the

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

Red List of Threatened Species 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 an inventory of the global conservation status and extinction risk of biological spe ...

. The species is listed in Appendix II of

CITES CITES (shorter acronym 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 inte ...

meaning international trade is regulated through the CITES permit system.

Snakebites

The Kenyan who collected the first specimens was bitten by an adult, with a single

fang A fang is a long, pointed tooth. In mammals, a fang is a modified maxillary tooth, used for biting and tearing flesh. In snakes, it is a specialized tooth that is associated with a venom gland (see snake venom). Spiders also have external fangs, ...

penetrating his right index finger. There was significant swelling and pain. A

tourniquet A tourniquet is a device that is used to apply pressure to a limb or extremity in order to create ischemia or stopping the flow of blood. It may be used in emergencies, in surgery, or in post-operative rehabilitation. A simple tourniquet can ...

was applied and an unknown antivenin was administered, after which the patient made a full recovery. It is doubtful, however, that the antivenin made any difference in this case, for no antivenin is known to be effective. Nevertheless, since these snakes are relatively large (for ''Atheris'') and their venom is known to contain powerful

anticoagulant An anticoagulant, commonly known as a blood thinner, is a chemical substance that prevents or reduces the coagulation of blood, prolonging the clotting time. Some occur naturally in blood-eating animals, such as leeches and mosquitoes, which ...

s, a bite should be taken seriously. Poor

coagulation Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a thrombus, blood clot. It results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The process of co ...

may even require

blood transfusion Blood transfusion is the process of transferring blood products into a person's Circulatory system, circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used ...

References

External links

CoP13, Prop. 30
a
CITES
Accessed 8 October 2006.
Mount Kenya bush viper (''Atheris desaixi'' ), Kenya
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Dr. Zoltan Takacs Homebase
Accessed 9 October 2006. {{Taxonbar, from=Q2869038 desaixi Snakes of Africa Reptiles of Kenya Endemic fauna of Kenya Reptiles described in 1968