''Atheris barbouri'' is a small and rare species of

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

viper 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 tha ...

endemic Endemism is the state of a species being found 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 found elsew ...

to the Uzungwe and Ukinga mountains of south-central Tanzania in Africa.Spawls S, Branch B (1995). ''The Dangerous Snakes of Africa''. Dubai: Ralph Curtis Books / Oriental Press. 192 pp. .

Taxonomy

The specific name, ''barbouri'', is in honor of

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...

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 rept ...

Thomas Barbour Thomas Barbour (August 19, 1884 – January 8, 1946) was an American herpetologist. From 1927 until 1946, he was director of the Harvard Museum of Comparative Zoology (MCZ) founded in 1859 by Louis Agassiz at Harvard University in Cambridge, Ma ...

. Beolens B, Watkins M, Grayson M (2011). ''The Eponym Dictionary of Reptiles''. Baltimore: Johns Hopkins University Press. xiii + 296 pp. . (''Adenorhinus barbouri'', p. 16). Common names for include Uzungwe viper,'''' Barbour's viper, worm-eating viper, Barbour's short-headed viper, Mallow D,

Ludwig D Ludwig may refer to: People and fictional characters * Ludwig (given name), including a list of people and fictional characters * Ludwig (surname), including a list of people * Ludwig Ahgren, or simply Ludwig, American YouTube live streamer and co ...

, Nilson G (2003). ''True Vipers: Natural History and Toxinology of Old World Vipers''. Malabar, Florida: Krieger Publishing Company. 359 pp. . and Uzungwe mountain bush viper. No

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

are recognized. ''Atheris barbouri'' was originally described in 1930 as a member of the genus ''

Atheris ''Atheris'' is a genus of vipers known as bush vipers.Spawls S, Branch B (1995). ''The Dangerous Snakes of Africa''. Ralph Curtis Books. Dubai: Oriental Press. 192 pp. . They are found only in tropical subsaharan Africa (excluding southern Afri ...

'' (bush vipers). In 1978, it was assigned to the genus ''Adenorhinos'' by Dowling & Duellman. It differs morphologically from the ''Atheris'' group, but recent research by

Lenk Lenk im Simmental (or simply Lenk) is a Municipalities of Switzerland, municipality in the Obersimmental-Saanen (administrative district), Obersimmental-Saanen administrative district in the Cantons of Switzerland, canton of Bern (canton), Bern i ...

et al. (2001) suggests that it is closely related to the

sympatric In biology, two related species or populations are considered sympatric when they exist in the same geographic area and thus frequently encounter one another. An initially interbreeding population that splits into two or more distinct species sh ...

species, ''

Atheris ceratophora :''Common names: Usambara bush viper,Spawls S, Branch B. 1995. The Dangerous Snakes of Africa. Ralph Curtis Books. Dubai: Oriental Press. 192 pp. . horned bush viper, eyelash bush viper, more.'' ''Atheris ceratophora'' is a venomous viper specie ...

'', even though it differs morphologically from all other members of the genus ''

''. It was returned to the genus ''Atheris'' by

Menegon Menegon is an Italian surname. Notable people with the surname include: * Andrea Menegon (born 1988), Italian footballer * Daniela Menegon (born 1977), Swazi swimmer *Lyndon Menegon Lyndon Menegon (born 11 February 1948) is an Australian former ...

et al. in 2011. Future research will show whether ''A. barbouri'' should be moved back to ''Adenorhinus'', or that ''Atheris ceratophora'' and ''A. barbouri'' should form a separate

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

. ''Atheris barbouri'' is similar to '' Montatheris hindii'' and '' Proatheris superciliaris'', which are also both terrestrial species from

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

, as well as previous members of the ''Atheris'' group.

Description

''Atheris barbouri'' is a small species reaching only in total length (including tail). The head is broad, triangular and distinct from the neck. The snout is short and rounded. The head is covered with small, strongly keeled, imbricate scales. The eyes are prominent, about 1.5 times larger than the distance to the mouth. The nostril is in an extreme forward position and is part of a single

nasal scale In reptiles, the nasal scale refers to the scale that encloses the nostril.Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Malabar, Florida: Krieger Publishing Company. 359 pp. . Sometimes this ...

that touches the

preocular scale In scaled reptiles, the ocular scales are those forming the margin of the eye.Wright AH, Wright AA. 1957. ''Handbook of Snakes''. Comstock Publishing Associates (7th printing, 1985). 1105 pp. . The name originates from the term ''oculus'' which ...

. The body is moderately slender, while the tail is relatively short, shorter than other species in the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

'', and not

prehensile Prehensility is the quality of an appendage or organ (anatomy), organ that has Adaptation (biology), adapted for grasping or holding. The word is derived from the Latin term ''prehendere'', meaning "to grasp". The ability to grasp is likely der ...

. The

dorsal scales 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 ...

are arranged in 20-23 rows at midbody, and are strongly keeled, except for those in the outermost rows, which are smooth.

Ventral scales 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 conta ...

number 116-122 and are rounded.

Subcaudals In snakes, the subcaudal scales are the enlarged plates on the underside of the tail.Wright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates (7th printing, 1985). 1105 pp. . These scales may be either single or divided (pair ...

are 19-23 and are single (undivided). The

anal plate Anal may refer to: Related to the anus *Related to the anus of animals: ** Anal fin, in fish anatomy ** Anal vein, in insect anatomy ** Anal scale, in reptile anatomy *Related to the human anus: ** Anal sex, a type of sexual activity involving ...

is single.U.S. Navy (1965). ''Poisonous Snakes of the World''. Washington, District of Columbia: United States Government Printing Office. 212 pp. The color pattern consists of a brown to blackish brown ground color with a pair of zigzag stripes that run dorsolaterally from the back of the head to the end of the tail. These stripes may form an irregular chain of darker rhombic blotches down the back. The tail may have a faint, black checkering. The belly color is greenish white to olive.

Distribution and habitat

The range of ''A. barbouri'' is extremely limited. It is known only from the Uzungwe and Ukinga mountains of south-central Tanzania. The type locality is "Dabaga, Uzungwe Mountains, southeast of Iringa, Tanganyika Territory, altitude " (= Udzungwe Mountains, Tanzania). A

species, ''A. barbouri'' is found in bushes and

bamboo Bamboos are a diverse group of evergreen perennial flowering plants making up the subfamily Bambusoideae of the grass family Poaceae. Giant bamboos are the largest members of the grass family. The origin of the word "bamboo" is uncertain, bu ...

undergrowth on mountain slopes at . It would seem that moist forest

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s are preferred, but it has also been found in gardens of tea farms.Spawls S, Howell K, Drewes R, Ashe J (2004). ''A Field Guide to the Reptiles of East Africa''. Waltham, Massachusetts: Academic Press. 543 pp. .

Behavior and ecology

Little is known about the behavior of ''A. barbouri''. It was first thought to be a

burrow An Eastern chipmunk at the entrance of its burrow A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of locomotion. Burrows provide a form of sh ...

ing species, but this is not likely as it has no obvious morphological adaptations for even a semifossorial life.

Feeding

It is believed that ''A. barbouri'' specializes in eating

slug Slug, or land slug, is a common name for any apparently shell-less terrestrial gastropod mollusc. The word ''slug'' is also often used as part of the common name of any gastropod mollusc that has no shell, a very reduced shell, or only a smal ...

earthworm An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. Th ...

s, and other soft-bodied

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s, and possibly also

frog A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...

Reproduction

''Atheris barbouri'' is apparently

oviparous Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and ...

. In February 1930, three females were collected that each contained 10

eggs Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especial ...

. The largest egg measured .

Venom

No information is available regarding the venom of ''A. barbouri'', its composition, its

toxicity Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subst ...

, or the effects of a

bite Biting is a common zoological behavior involving the active, rapid closing of the jaw around an object. This behavior is found in toothed animals such as mammals, reptiles, amphibians and fish, but can also exist in arthropods. Myocytic con ...

. No cases of envenomation have been recorded. However, because of the very limited distribution, bites are unlikely to occur.