Proatheris superciliaris

Superregnum: Eukaryota
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Superphylum: Deuterostomia
Phylum: Chordata
Cladus: Craniata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Superclassis: Tetrapoda
Cladus: Reptiliomorpha
Cladus: Amniota
Classis: Reptilia
Cladus: Eureptilia
Cladus: Romeriida
Subclassis: Diapsida
Cladus: Sauria
Infraclassis: Lepidosauromorpha
Superordo: Lepidosauria
Ordo: Squamata
Subordo: Serpentes
Infraordo: Caenophidia
Superfamilia: Viperoidea

Familia: Viperidae
Subfamilia: Viperinae
Genus: Proatheris
Species:Proatheris superciliaris

Proatheris (commonly referred to as the lowland viper and swamp viper among other names) is a monotypic genus created for the venomous viper species, Proatheris superciliaris. This is a small terrestrial species endemic to East Africa.[2] No subspecies are currently recognized.[3]

Description

Proatheris superciliaris is a small species that averages 40 to 50 cm (about 16 to 20 inches) in total length (body + tail), with a maximum total length of 61 cm (24 in). The females are slightly larger than the males. The head has a somewhat elongated appearance, the top of which is covered with small scales except for a pair of large supraocular scales, which are almost twice as long as they are wide.[4]
Common names

Common names for the Proatheris include the lowland viper, swamp viper,[2] lowland swamp viper,[5] eyebrow viper, swamp adder,[4] Peter's viper, flood-plain viper,[6] Mozambique viper, African lowland viper,[7] and the domino viper.[8]
Geographic range

It is found in East Africa. The southern part of its range begins near Beira, in central Mozambique, extends up north over the Mozambique Plain to Quissanga, and through Malawi and as far north as the floodplains of southern Tanzania at the northern end of Lake Malawi.

The type locality given is "Terra Querimba" (= Quissanga mainland opposite Ilha Quirimba, Mozambique).[1]

Its range is apparently centered on the lower section of the Zambezi River and spreads out into the coastal plain of central Mozambique and the Shire Valley to Lake Chilwa and Malawi. However, other specimens have been found far from this region, such as in Cape Delgado Province, in north-eastern Mozambique, and Mwaya in south-western Tanzania.[2]
Habitat

It is almost always found in low-lying marshes, floodplains and land frequently used for grazing cattle. The soil is never too dry, since this would make it difficult for the rodents that they feed on to dig their burrows. These snakes are entirely terrestrial and are usually found in or around these rodent burrows.[4]
Behaviour

One of the distinguishing characteristics of the Atheris group (to which Proatheris is closely related), is that they have prehensile tails. With Proatheris, the young and subadults have this capability, but it is diminished in the adults.[4]
Feeding

Preys mainly on small frogs and toads. Occasionally, it also feeds on small rodents.[2]
Reproduction

This species is viviparous, with typically 3-16 neonates.[9]
Venom

The first known case of a survivor of snakebite by this species was reported by Els (1988), involving a 20 cm (7.9 in) juvenile and 24-year-old victim penetrated by a single fang. The results were painful, but there were none of the strongly hemotoxic symptoms that had been associated with Atheris venom up to that point.[4]

In a second case in 1996, a victim experienced severe hemolysis and complete platelet destruction after which his liver and kidneys began to fail. When it was feared that the patient might die from hemolytic-uremic syndrome, plasmapheresis was performed. Luckily, the patient survived, but it is now obvious that P. superciliaris venom is very hemotoxic.[10]
Taxonomy

This species was previously placed in the genus Atheris based on skull characteristics and because of its partially prehensile tail.[4]
Etymology

The generic name, Proatheris, is Latin for "before-atheris".[6]
References

Mac Diarmid, Roy W.; Campbell, Jonathan A.; Touré, TŚhaka A. (1999). Snake Species of the World: A Taxonomic and Geographic Reference. Volume 1. Washington, DC: The Herpetologists' League. ISBN 978-1-893777-01-9. Retrieved 29 November 2013.
Spawls S, Branch B. 1995. The Dangerous Snakes of Africa. Dubai: Ralph Curtis Books. Oriental Press. 192 pp. ISBN 0-88359-029-8.
"Proatheris superciliaris". Integrated Taxonomic Information System. Retrieved 31 July 2006.
Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Malabar, Florida: Krieger Publishing Company. 359 pp. ISBN 0-89464-877-2.
Proatheris superciliaris at the Reptarium.cz Reptile Database. Accessed 9 August 2007.
Proatheris superciliaris at The World Of Atheris. Accessed 9 September 2007.
Brown JH. 1973. Toxicology and Pharmacology of Venoms from Poisonous Snakes. Springfield, Illinois: Charles C. Thomas. 184 pp. LCCCN 73-229. ISBN 0-398-02808-7.
U.S. Navy. 1991. Poisonous Snakes of the World. US Govt. New York: Dover Publications Inc. 203 pp. ISBN 0-486-26629-X.
O'Shea, Mark (2008). Venomous Snakes of the World. London, United Kingdom: New Holland Publishers Ltd. p. 83. ISBN 1-84773-086-8.

Venom at The World Of Atheris. Accessed 9 September 2007.

Further reading

Boulenger, G.A. 1896. Catalogue of the Snakes in the British Museum (Natural History). Volume III., Containing the ... Viperidæ. London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiv + 727 pp. + Plates I.- XXV. (Vipera superciliaris, p. 491).
Branch, Bill. 2004. Field Guide to Snakes and Other Reptiles of Southern Africa. Third Revised edition, Second impression. Sanibel Island, Florida: Ralph Curtis Books. 399 pp. ISBN 0-88359-042-5. (Genus Proatheris, p. 119; Proatheris superciliaris, pp. 119–120 + Plate 14).
Broadley, D.G. 1996. A review of the tribe Atherini (Serpentes: Viperidae), with descriptions of two new genera. African Journal of Herpetology 45: 40-48. (Genus Proatheris).
Els R. 1988. Atheris superciliaris envenomation. J. Herpetol. Assoc. Africa 34: 52.
Marais J. 1992. A Complete Guide to the Snakes of Southern Africa. Malabar, Florida: Krieger Publishing. 248 pp.
Marx H., Rabb G.B. 1965. Phyletic analysis of fifty characters of advanced snakes. Field Zool. 63: 1-321.
Peters, W. 1854. Diagnosen neuer Batrachier, welche zusammen mit der früher (24. Juli und 17. August) gegebenen Übersicht der Schlangen und Eidechsen mitgelheilt werden. Bericht über die zur Bekanntmachung geeigheten Verhandlugen der Königl. Preuss. Akademie der Wissenschaften zu Berlin 1854: 614-628. (Vipera superciliaris, p. 625).
Stevens RA. 1973. A report on the lowland viper, Atheris superciliaris from the Lake Chilwa floodplain of Malawi. Arnoldia (Rhodesia) 22: 1-22.