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Family: Viperidae
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Subfamily: Viperinae
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Genus: Bitis
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Species: schneideri
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Common Names
Namaqua Dwarf Adder , Schneider's Adder , Spotted Dwarf Adder , Namaqua Puff Adder
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Local Names
Namakwa Dwergadder
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Region
Sub-Saharan Africa
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Countries
Namibia, South Africa
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Taxonomy and Biology
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Adult Length: 0.175 m
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General Shape
Very small ( world's smallest adder ), slightly depressed, stout bodied snake with a short tail. Can grow to a maximum of about 0.28 metres. Head is small, broad and rounded, small ridge over each eye with a small horn like scale and very distinct from narrow neck. Snout is short, rounded and canthus is distinct. Eyes are moderately small in size with vertically elliptical pupils and positioned on the side of the head. Dorsal scales are strongly keeled with apical pits ( except lower laterally bordering the ventrals ). Subcaudals are keeled ( but smooth proximally in males ).
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Habitat
Vegetated, coastal sand dune and sandy desert.
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Habits
Terrestrial, mainly nocturnal and a sidewinder. Often shuffles into the sand below grass tussocks leaving only its eyes exposed awaiting the ambush of prey. Uses its black tail tip to lure prey.
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Prey
Feeds mainly on small geckos, skinks but will feed on frogs and rodents.
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Venom
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General: Venom Neurotoxins
Unknown
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General: Venom Myotoxins
Unknown
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General: Venom Procoagulants
Unknown
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General: Venom Anticoagulants
Unknown
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General: Venom Haemorrhagins
Unknown
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General: Venom Nephrotoxins
Unknown
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General: Venom Cardiotoxins
Unknown
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General: Venom Necrotoxins
Unknown
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General: Venom Other
Unknown
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Clinical Effects
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General: Dangerousness
Mild envenoming only, not likely to prove lethal
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General: Rate of Envenoming: Unknown
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General: Untreated Lethality Rate: Unknown
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General: Local Effects
Local pain, swelling & bruising
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General: Local Necrosis
Insufficient clinical reports to know
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General: General Systemic Effects
Variable non-specific effects which may include headache, nausea, vomiting, abdominal pain, diarrhoea, dizziness, collapse or convulsions
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General: Neurotoxic Paralysis
Unlikely to occur
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General: Myotoxicity
Not likely to occur
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General: Coagulopathy & Haemorrhages
No reports of coagulopathy, though related species can cause bleeding problems
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General: Renal Damage
Unlikely to occur
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General: Cardiotoxicity
Unlikely to occur
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General: Other
Unknown
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First Aid
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Description: First aid for bites by Viperid snakes likely to cause significant local injury at the bite site (see listing in Comments section).
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Details
1. After ensuring the patient and onlookers have moved out of range of further strikes by the snake, the bitten person should be reassured and persuaded to lie down and remain still. Many will be terrified, fearing sudden death and, in this mood, they may behave irrationally or even hysterically. The basis for reassurance is the fact that many venomous bites do not result in envenoming, the relatively slow progression to severe envenoming (hours following elapid bites, days following viper bites) and the effectiveness of modern medical treatment. 2. The bite wound should not be tampered with in any way. Wiping it once with a damp cloth to remove surface venom is unlikely to do much harm (or good) but the wound must not be massaged. 3. All rings or other jewellery on the bitten limb, especially on fingers, should be removed, as they may act as tourniquets if oedema develops. 4. The bitten limb should be immobilised as effectively as possible using an extemporised splint or sling; if available, crepe bandaging of the splinted limb is an effective form of immobilisation. 5. If there is any impairment of vital functions, such as problems with respiration, airway, circulation, heart function, these must be supported as a priority. In particular, for bites causing flaccid paralysis, including respiratory paralysis, both airway and respiration may be impaired, requiring urgent and prolonged treatment, which may include the mouth to mask (mouth to mouth) technique of expired air transfer. Seek urgent medical attention. 6. Do not use Tourniquets, cut, suck or scarify the wound or apply chemicals or electric shock. 7. Avoid peroral intake, absolutely no alcohol. No sedatives outside hospital. If there will be considerable delay before reaching medical aid, measured in several hours to days, then give clear fluids by mouth to prevent dehydration. 8. If the offending snake has been killed it should be brought with the patient for identification (only relevant in areas where there are more than one naturally occurring venomous snake species), but be careful to avoid touching the head, as even a dead snake can envenom. No attempt should be made to pursue the snake into the undergrowth as this will risk further bites. 9. The snakebite victim should be transported as quickly and as passively as possible to the nearest place where they can be seen by a medically-trained person (health station, dispensary, clinic or hospital). The bitten limb must not be exercised as muscular contraction will promote systemic absorption of venom. If no motor vehicle or boat is available, the patient can be carried on a stretcher or hurdle, on the pillion or crossbar of a bicycle or on someone's back. 10. Most traditional, and many of the more recently fashionable, first aid measures are useless and potentially dangerous. These include local cauterization, incision, excision, amputation, suction by mouth, vacuum pump or syringe, combined incision and suction ("venom-ex" apparatus), injection or instillation of compounds such as potassium permanganate, phenol (carbolic soap) and trypsin, application of electric shocks or ice (cryotherapy), use of traditional herbal, folk and other remedies including the ingestion of emetic plant products and parts of the snake, multiple incisions, tattooing and so on.
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Treatment
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Treatment Summary
Namaqua dwarf adder bites apparently cause only local pain & swelling, but more severe local effects cannot be excluded, therefore all cases should be fully assessed and observed for at least 12 hrs. If significant local effects occur, manage as for other Bitis species.
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Key Diagnostic Features
Local swelling, blistering, necrosis
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General Approach to Management
It is possible that most cases will be minor, but some cases may be more severe, requiring admission and treatment, so assess carefully before discharge.
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Antivenom Therapy
No antivenom available
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1. Antivenom Code: SAfSAI03
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Antivenom Name: SAIMR Polyvalent Antivenom
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Manufacturer: South African Vaccine Producers (Pty) Ltd
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Phone: +27 11 386-6000; +27 11 386-6078
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Address: Postal address PO Box 28999 Sandringham 2131 Gauteng Province
Physical address 1 Modderfontein Road Sandringham, Johannesburg
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Country: South Africa
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2. Antivenom Code: SAfSAIBK
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Antivenom Name: SAIMR Snakebite Kit
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Manufacturer: South African Vaccine Producers (Pty) Ltd
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Phone: +27 11 386-6000; +27 11 386-6078
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Address: Postal address PO Box 28999 Sandringham 2131 Gauteng Province
Physical address 1 Modderfontein Road Sandringham, Johannesburg
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Country: South Africa
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3. Antivenom Code: SAfAVC02
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Antivenom Name: Polyvalent Snake Antivenom
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Manufacturer: National Antivenom and Vaccine Production Centre
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Phone: ++966-1-252-0088 ext 45626, 45637.
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Address: P.O. Box 22490 Riyadh 11426
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Country: Saudi Arabia
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