| Adenorhinos barbouri|
Adenorhinos is a monotypic genus created for a venomous viper species, A. barbouri. This is a small and exceptionally rare terrestrial species found only in the Uzungwe and Ukinga mountains of south-central Tanzania in Africa. No subspecies are recognized.
This is a small species, reaching only 40 cm in length. 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 that touches the preocular scale.
The body is moderately slender while the tail is relatively short -- shorter than Atheris and not prehensile. Dorsal scales strongly keeled, 20-23 rows at midbody. Outermost rows smooth. Ventral scales 116-122 and rounded. Subcaudals 19-23, single. Anal plate single.
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.
This snake's range 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 6000 feet" (Udzungwe Mountains, Tanzania).
Little is known. It was first thought to be a burrowing species, but this is not likely as it has no obvious morphological adaptations for even a semifossorial life.
This species is apparently oviparous. In February 1930, three females were collected that each contained 10 eggs. The largest egg measured 1.0 x 0.6 cm.
No information is available regarding the composition of the venom, its toxicity or the effects of a bite. No cases of envenomation have been recorded. However, because of the very limited distribution, bites are unlikely to occur.
A. barbouri was previously described as a member of the genus Atheris (bush vipers). It differs morphologically from the Atheris group, but recent research by Lenk et al. (2001) suggests that it is closely related to the sympatric species, Atheris ceratophora, even though it differes morphologically from all other members of the genus Atheris. Future research will show whether A. barbouri should be moved back to Atheris, or that Atheris ceratophora and A. barbouri should form a separate clade.
- list of viperine species and subspecies
- True vipers - Common names.
- True vipers - Synonymy.
- McDiarmid RW, Campbell JA, Touré T. 1999. Snake Species of the World: A Taxonomic and Geographic Reference, vol. 1. Herpetologists' League. 511 pp. ISBN 1-893777-00-6 (series). ISBN 1-893777-01-4 (volume).
- Spawls S, Branch B. 1995. The Dangerous Snakes of Africa. Ralph Curtis Books. Dubai: Oriental Press. 192 pp. ISBN 0-88359-029-8.
- Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Krieger Publishing Company. 359 pp. ISBN 0-89464-877-2.
- The World of Atheris - Adenorhinos barbouri
- Adenorhinos (TSN 634418) at Integrated Taxonomic Information System. Accessed 18 March 2007.
- U.S. Navy. 1965. Poisonous Snakes of the World. US Govt. Printing Office, Washington D.C. 212 pp.
- Species Adenorhinos barbouri at the Species2000 Database
- Spawls S, Howell K, Drewes R, Ashe J. 2004. A Field Guide to the Reptiles of East Africa. Academic Press. 543 pp. ISBN 0-7136-6817-2.
- Lenk P, Kalyabina S, Wink M, Joger U. 2001. Evolutionary relationships among the true vipers (Reptilia: Viperidae) inferred from mitochondrial DNA sequences. Molecular Phylogenics and Evolution 19(1):94-104.