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Family: Lamprophiidae
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Subfamily: Aparallactinae
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Genus: Macrelaps
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Species: microlepidotus
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Common Names
Natal Black Snake
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Local Names
Natalse Swartslang
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Region
Sub-Saharan Africa
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Countries
South Africa
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Taxonomy and Biology
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Adult Length: 0.80 m
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General Shape
Medium in length, cylindrical, relatively thick bodied snake with a short tail. Can grow to a maximum of about 1.15 metres. Head is small, short, blunt, conical and indistinct from neck. Maxillary is short. Eyes are very small in size with round pupils. Fangs located beneath the eye and are not hinged. Scales are smooth but feebly keeled in anal region. Dorsal scale count usually 23 - 25 - ( 19 or 21 ).
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Habitat
Lives underground in damp coastal bush and riverine forest habitat. Has also been found in urban gardens.
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Habits
Nocturnal and fossorial. Burrows in moist leaf litter and humid soil. Emerges onto the surface on warm and damp nights. It has bee observed swimming and is a good swimmer. Docile temperament and rarely bites even when handled.
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Prey
Small mammals, frogs, skinks and other snakes. Prey is captured, restrained in the body coils and chewed to introduce venom.
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Venom
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General: Venom Neurotoxins
Unknown, but probably not present
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General: Venom Myotoxins
Unknown, but probably not present
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General: Venom Procoagulants
Unknown, but probably not present
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General: Venom Anticoagulants
Unknown, but probably not present
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General: Venom Haemorrhagins
Unknown, but probably not present
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General: Venom Nephrotoxins
Unknown, but probably not present
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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
Unknown, but potentially severe envenoming, though unlikely, cannot be excluded.
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General: Rate of Envenoming: Unknown but likely to be moderate
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General: Untreated Lethality Rate: Unknown but lethal potential cannot be excluded
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General: Local Effects
Insufficient clinical reports to know, but possibly marked local effects; pain, severe swelling, bruising, blistering, necrosis
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General: Local Necrosis
Insufficient clinical reports to know
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General: General Systemic Effects
Insufficient clinical reports to know, but possibly variable non-specific effects which may include headache, nausea, vomiting, abdominal pain, diarrhoea, dizziness, collapse or convulsions
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General: Neurotoxic Paralysis
Insufficient clinical reports to know, but probably does not occur
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General: Myotoxicity
Insufficient clinical reports to know, but probably does not occur
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General: Coagulopathy & Haemorrhages
Insufficient clinical reports to know, but probably does not occur
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General: Renal Damage
Insufficient clinical reports to know, but probably does not occur
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General: Cardiotoxicity
Unknown
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General: Other
Insufficient clinical reports to know
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First Aid
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Description: First aid for bites by Atractaspid snakes (mole vipers, burrowing asps)
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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. 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
Burrowing asp bites mostly cause minor effects, but severe local effects, including necrosis, can occur, as can potentially lethal systemic effects, so all cases should be urgently assessed, have ongoing cardiac monitoring, receive supportive & symptomatic treatment. Antivenom is not generally available.
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Key Diagnostic Features
Unexplained loss of consciousness without known etiology
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General Approach to Management
All cases should be treated as urgent & potentially lethal. Rapid assessment & commencement of treatment including appropriate antivenom (if indicated & available) is mandatory. Admit all cases.
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Antivenom Therapy
No antivenom available
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