Heterodon nasicus
Family: Colubridae
Subfamily: Dipsadinae
Genus: Heterodon
Species: nasicus
Subspecies: nasicus , gloydi , kennerlyi
Common Names
Western Hognose Snake ( H. nasicus ) , Plains Hognose Snake ( H. n. nasicus ) , Dusty Hognose Snake ( H. n. gloydi ) , Mexican Hognose Snake ( H. n. kennerlyi )
Local Names
Culebra Nariz de Cerdo Occidental ( H. nasicus ) , Hocico de Puerco ( H. n. kennerlyi )
Region
North America + Central America
Countries
Mexico, United States of America
 
Taxonomy and Biology
Adult Length: 0.60 m
General Shape
Small in length, stout, heavy bodied snake with a short tail. Can grow to a maximum of about 0.90 metres. Head is slightly distinct from broad neck. Snout is sharply pointed and distinctly upturned. Eyes are medium in size with round pupils. Dorsal scales are keeled with apical pits.
Habitat
Up to about 2500 metres in sand and gravel locations in prairie, semi-desert, open woodlands, scrublands, farmlands and river flood plains.
Habits
Mainly diurnal and terrestrial, most active during early morning and late afternoon. Uses its snout for digging in loose soil. Burrows into loose soil to escape the heat or cold. If disturbed it will spread its head and neck, and strike with an open mouth, seldom biting. Often feigns death.
Prey
Feeds mainly on rodents, small mammals. toads, frogs, lizards, snakes and the eggs of reptiles and amphibians.
Species Map
Small (Approx 20k) version
 
Venom
General: Venom Neurotoxins
Non-venomous
General: Venom Myotoxins
Non-venomous
General: Venom Procoagulants
Non-venomous
General: Venom Anticoagulants
Non-venomous
General: Venom Haemorrhagins
Non-venomous
General: Venom Nephrotoxins
Non-venomous
General: Venom Cardiotoxins
Non-venomous
General: Venom Necrotoxins
Non-venomous
General: Venom Other
Non-venomous
 
Clinical Effects
General: Dangerousness
Non-venomous, so no likelihood of envenoming or lethality
General: Rate of Envenoming: Non-venomous, so essentially all bites should be "dry".
General: Untreated Lethality Rate: Non-venomous, so no likelihood of envenoming or lethality
General: Local Effects
Mild local effects possible
General: Local Necrosis
Not likely to occur
General: General Systemic Effects
General systemic effects unlikely
General: Neurotoxic Paralysis
Does not occur, based on current clinical evidence
General: Myotoxicity
Does not occur, based on current clinical evidence
General: Coagulopathy & Haemorrhages
Does not occur, based on current clinical evidence
General: Renal Damage
Does not occur, based on current clinical evidence
General: Cardiotoxicity
Does not occur, based on current clinical evidence
General: Other
Not likely to occur
 
First Aid
Description: First aid for bites by non-front-fanged colubroid snakes likely to cause either no effects or only mild local effects.
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.
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.
 
Treatment
Treatment Summary
Bites by this species are not expected to cause medically significant effects and the only risk, probably small, is local secondary infection. Patients presenting with bites by these snakes do not require medical attention, other than to check for infection and ensure tetanus immune status. Patients should be advised to return if local symptoms develop, suggesting secondary infection.
Key Diagnostic Features
Bites unlikely to cause more than mild to moderate local swelling & pain, occasionally local bruising, paresthesia/numbness, erythema or bleeding, but no necrosis and no systemic effects.
General Approach to Management
While most cases will be minor, not requiring admission, some cases will be more severe, requiring admission and treatment, so assess carefully before early discharge.
Antivenom Therapy
No antivenom available
Antivenoms
No Antivenoms
 
Images
No images for Images