Several factors involved in snake bites make superlatives such as “most venomous” difficult to bestow accurately. In addition to differences in venom potency and typical yield between various species, venoms affect mice -- the usual test subject -- and people quite differently. For mice, the desert horned viper has the most potent venom of any snake in the Sahara; however, bites from saw-scaled vipers or Nubian cobras are often more serious for people.
Desert Horned Viper
The most common venomous snakes in the Sahara -- and the only ones likely to be encountered in the sand dunes -- are desert horned vipers (Cerastes cerastes). Named for their distinctive “horns” located over each eye, horned desert vipers are very similar to the sidewinders of the United States. Desert horned viper bites are usually very painful, and in some cases have proven fatal. Their venom features 13 different toxins; however, desert horned vipers are generally not as dangerous to humans as some of the other species of the Sahara.
Saw Scaled Vipers
Eleven species of carpet, or saw-scaled viper comprise the genus Echis and resemble each other in terms of behavior and ecology. These small vipers, which are usually less than 2 feet in length, are among the most dangerous snakes in the world. The group, spanning much of Africa, the Middle East and south Asia, possess virulent venom -- though it does vary by species -- and an irascible nature, making them quick to bite the foot that trods upon them. Saw scaled vipers are so-named for their habit of rubbing their body scales against each other to produce a loud, raspy sound to warn potential predators of the snake’s venomous bite.
Nubian Spitting Cobras
Nubian cobras (Naja nubiae) are medium-sized cobras that frequent portions of the Sahara. In addition to their potentially deadly bite, Nubian spitting cobras are capable of spitting venom at the eyes of perceived predators. While most spitting cobra venoms primarily cause localized, rather than systemic effects, Nubian spitting cobra venom is very lethal to mice -- even when researchers administer antivenom.
Lesser Known Species
Numerous other venomous snakes inhabit the Sahara, but most are not as dangerous as the vipers and cobras of the region. Moorish (Daboia mauritanica) and desert vipers (Daboia deserti) are small to medium-sized snakes, whose range encroaches into the Sahara. Though both species are related to the deadly Russel’s viper (Daboia russelii) of Asia, they are probably not as dangerous as their larger cousins. Experimental studies testing desert viper venom on mice have shown it to be relatively weak, though capable of causing excessive bleeding and bruising. Species specific antivenom does not exist for the poorly known Lataste’s viper (Vipera latastei) who also lives in portions of the Sahara.
- World Health Organization: Snake Antivenoms
- Desert USA: The Desert Horned Viper
- Oxford Journal of Medicine: Life-threatening Envenoming by the Saharan Horned Viper (Cerastes Cerastes) Causing Micro-Angiopathic Haemolysis, Coagulopathy and Acute Renal Failure: Clinical Cases and Review
- Journal of Proteome Research: Snake Venomics of African Spitting Cobras: Toxin Composition and Assessment of Congeneric Cross-Reactivity of the Pan-African EchiTAb-Plus-ICP Antivenom by Antivenomics and Neutralization Approaches.
- The Wild Classroom: Most Venomous Snakes
- Toxicon: Neutralization of Vipera and Macrovipera Venoms by Two Experimental Polyvalent Antisera: A Study of Paraspeciﬁcity
- Mark Oshea's Reptile World: West African Carpet Viper
- Arkive: Nubian Spitting Cobra
- Digital Vision./Photodisc/Getty Images