:''Common names: Namaqua dwarf adder, Mallow D, Ludwig D, Nilson G (2003). ''True Vipers: Natural History and Toxinology of Old World Vipers''. Malabar, Florida: Krieger Publishing Company. 359 pp. . Spawls S, Branch B (1995). ''The Dangerous Snakes of Africa''. Dubai: Ralph Curtis Books. Oriental Press. 192 pp. . spotted dwarf adder, Schneider's adder.'' ''Bitis schneideri'' is a

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), ...

venomous snake ''Venomous snakes'' are species of the suborder Serpentes that are capable of producing venom, which they use for killing prey, for defense, and to assist with digestion of their prey. The venom is typically delivered by injection using hollow ...

in the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Viperinae Viperinae, or viperines, are a subfamily of vipers endemic to Europe, Asia and Africa. They are distinguished by their lack of the heat-sensing pit organs that characterize their sister group, the subfamily Crotalinae. Currently, 13 genera are r ...

of the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Viperidae 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 snake, venomous and have long (relat ...

. The species is native to a small coastal region that straddles the border between

Namibia Namibia, officially the Republic of Namibia, is a country on the west coast of Southern Africa. Its borders include the Atlantic Ocean to the west, Angola and Zambia to the north, Botswana to the east and South Africa to the south; in the no ...

and

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

. ''B. schneideri'' is the smallest species in the

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

Bitis ''Bitis'' is a genus of Viperidae, vipers found in Africa and the southern Arabian Peninsula. It includes the largest and the smallest vipers in the world. Members are known for their characteristic Deimatic behaviour, threat displays that invol ...

'' and possibly the world's smallest

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 ...

. There are 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 ...

that are currently recognized as being valid.

Etymology

The specific name, ''schneideri'', was given by

Oskar Boettger Oskar Boettger (; 31 March 1844 – 25 September 1910) was a German zoologist who was a native of Frankfurt am Main. He was an uncle of the noted malacologist Caesar Rudolf Boettger (1888–1976). From 1863 to 1866 he studied at the Bergakademie ...

in honor of "''Dr. Oskar Schneider in

Dresden Dresden (; ; Upper Saxon German, Upper Saxon: ''Dräsdn''; , ) is the capital city of the States of Germany, German state of Saxony and its second most populous city after Leipzig. It is the List of cities in Germany by population, 12th most p ...

'' ", a friend of Boettger. Oskar Schneider (1841–1903) was a conchologist.

Description

With an average total length (including tail) of 18–25 cm (7–10 in) and a maximum reported total length of , ''B. schneideri'' is the smallest species of the genus ''

'' and possibly the world's smallest viperid.

Geographic range and habitat

''Bitis schneideri'' ranges from the white coastal sand dunes of Namibia, near Lüderitz, south to Hondeklip Bay, Little Namaqualand,

. Mallow et al. (2003) describe the range as the transitional regions of the

Namib Desert The Namib ( ; ) is a coastal desert in Southern Africa. According to the broadest definition, the Namib stretches for more than along the Atlantic coasts of Angola, Namibia, and northwest South Africa, extending southward from the Carunjamba Ri ...

. The viper's habitat comprises a comparatively narrow strip of coastal dunes that appears to be characterized by particularly low

seasonality In time series data, seasonality refers to the trends that occur at specific regular intervals less than a year, such as weekly, monthly, or quarterly. Seasonality may be caused by various factors, such as weather, vacation, and holidays and consi ...

, i.e. small temperature differences between seasons. The range may extend up to inland in the Sperrgebiet of southern Namibia. The type locality given is "Angra Pequenia" Lüderitz Bay, Namibia">Lüderitz_Bay.html" ;"title="Lüderitz Bay">Lüderitz Bay, Namibia

Ecology

Populations of ''B. schneideri'' naturally appear to be subject to unusually high annual Mortality rate">mortality (39–56%) due to their small size and existence in a very predator-rich environment. As a consequence, it is likely that the species has evolved a higher rate of reproduction (once every year) than is usual among viperids, who commonly only reproduce every other year or more rarely. ''B. schneideri'' is Viviparity, viviparous.

Venom

An account is provided by Hurrell (1981) of a bite he sustained on his left index finger. The symptoms included intense pain, pronounced swelling, discoloration and oozing of serum from the punctures. After 24 hours, a 5 mm

hematoma A hematoma, also spelled haematoma, or blood suffusion is a localized bleeding outside of blood vessels, due to either disease or trauma including injury or surgery and may involve blood continuing to seep from broken capillaries. A hematoma is ...

developed at the bite site. His condition stabilized after three to four days, with the swelling and pain gradually subsiding. Healing was complete after two weeks, with no loss of function or sensation of the afflicted digit. Minimal local tissue damage and no

systemic effect An adverse drug reaction (ADR) is a harmful, unintended result caused by taking medication. ADRs may occur following a single dose or prolonged administration of a drug or may result from the combination of two or more drugs. The meaning of this ...

s were reported. No antivenin is available for this species.

References

External links

Namaqua dwarf adder (''Bitis schneideri)''
at

ARKive ARKive was a global initiative with the mission of "promoting the conservation of the world's threatened species, through the power of wildlife imagery", which it did by locating and gathering films, photographs and audio recordings of the wor ...

. {{Taxonbar, from=Q509622 schneideri Snakes of Africa Reptiles of Namibia Reptiles of South Africa Reptiles described in 1886 Taxa named by Oskar Boettger