Cerastes cerastes (common names: Saharan horned viper, horned desert viper, more) is a venomous viper species native to the deserts of Northern Africa and parts of the Middle East. It often is easily recognised by the presence of a pair of supraocular "horns", although hornless individuals do occur. No subspecies are currently recognised.
The average total length (body + tail) is 30–60 cm (12–24 in), with a maximum total length of 85 cm (33 in). Females are larger than males.
One of the most distinctive characteristics of this species is the presence of supraorbital "horns", one over each eye. However, these may be reduced in size or absent (see genus Cerastes). The eyes are prominent and set on the sides of the head. There is significant sexual dimorphism, with males having larger heads and larger eyes than females. Compared to C. gasperettii, the relative head size of C. cerastes is larger and there is a greater frequency of horned individuals (13% versus 48%, respectively).
The colour pattern consists of a yellowish, pale grey, pinkish, reddish, or pale brown ground colour that almost always matches the substrate colour where the animal is found. Dorsally, a series of dark, semi-rectangular blotches runs the length of the body. These blotches may or may not be fused into crossbars. The belly is white. The tail, which may have a black tip, is usually thin.
Common names of this species include Desert sidewinding horned viper  Saharan horned viper, horned desert viper, Sahara horned viper, desert horned viper, North African horned viper, African desert horned viper, greater cerastes, asp and horned viper. In Egypt it is called el-ṭorîsha (حية الطريشة); in Libya it is called "um-Goron" (ام قرون).
It is found in arid North Africa (Morocco, Mauritania and Mali, eastward through Algeria, Tunisia, Niger, Libya and Chad to Egypt, Sudan, Ethiopia and Somalia) through Sinai to the northern Negev of Israel. In the Arabian Peninsula, it occurs in Yemen, Kuwait, extreme southwestern Saudi Arabia and parts of the country in Qatar where it is sympatric with C. gasperettii. A report of this species being found in Lebanon is unlikely, according to Joger (1984).
These snakes favor dry, sandy areas with sparse rock outcroppings, and tend not to prefer coarse sand. Occasionally, they are found around oases, and up to an altitude of 1,500 metres (4,900 ft). Cooler temperatures, with annual averages of 20 °C or less, are preferred.
They typically move about by sidewinding, during which they press their weight into the sand or soil, leaving whole-body impressions. Often, it is even possible to use these impressions to make ventral scale counts. They have a reasonably placid temperament, but if threatened, they may assume a C-shaped posture and rapidly rub their coils together. Because they have strongly keeled scales, this rubbing produces a rasping noise, similar to the sound produced by snakes of the genus Echis. In the wild they are typically ambush predators, lying submerged in sand adjacent to rocks or under vegetation. When approached, they strike very rapidly, holding on to the captured prey (small birds and rodents) until the venom takes effect.
In captivity, mating was observed in April and always occurred while the animals were buried in the sand. This species is oviparous, laying 8–23 eggs that hatch after 50 to 80 days of incubation. The eggs are laid under rocks and in abandoned rodent burrows. The hatchlings measure 12–15 cm (about 5-6 inches) in total length.
C. cerastes venom is not very toxic, although it is reported to be similar in action to Echis venom. Envenomation usually causes swelling, haemorrhage, necrosis, nausea, vomiting, and haematuria. A high phospholipase A2 content may cause cardiotoxicity and myotoxicity. Studies of venom from both C. cerastes and C. vipera list a total of eight venom fractions, the most powerful of which has haemorrhagic activity. Venom yields vary, with ranges of 19–27 mg to 100 mg of dried venom being reported. For venom toxicity, Brown (1973) gives LD50 values of 0.4 mg/kg IV and 3.0 mg/kg SC. An estimated lethal dose for humans is 40–50 mg.
A number of subspecies may be encountered in literature:
- C. c. hoofieni Werner & Sivan, 1999 - Saudi Arabia.
- C. c. karlhartli Sochurek, 1974 - Egyptian horned viper - southeast Egypt and Sinai Peninsula.
- C. c. mutila Domergue, 1901 - Algerian horned viper - southwest Algeria, Morocco.
- List of viperine species and subspecies
- Viperinae by common name
- Viperinae by taxonomic synonyms
- Viper (hieroglyph)
- McDiarmid RW, Campbell JA, Touré T. 1999. Snake Species of the World: A Taxonomic and Geographic Reference, Volume 1. Washington, District of Columbia: Herpetologists' League. 511 pp. ISBN 1-893777-00-6 (series). ISBN 1-893777-01-4 (volume).
- Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Malabar, Florida: Krieger Publishing Company. 359 pp. ISBN 0-89464-877-2.
- Mehrtens JM. 1987. Living Snakes of the World in Color. New York: Sterling Publishers. 480 pp. ISBN 0-8069-6460-X.
- "Cerastes cerastes". Integrated Taxonomic Information System. Retrieved 30 July 2006.
- Spawls S, Branch B. 1995. The Dangerous Snakes of Africa. Dubai: Ralph Curtis Books. Oriental Press. 192 pp. ISBN 0-88359-029-8.
- Werner YL, Verdier A, Rosenman D, Sivan N. 1991. Systematics and Zoogeography of Cerastes (Ophidia: Viperidae) in the Levant: 1. Distinguishing Arabian from African "Cerastes cerastes". The Snake 23: 90-100.
- Austin Stevens: SNAKEMASTER In Search of the Snake that Killed Cleopatra, 2005. [DVD] Michael Davies, USA: Discovery Communications, Inc.
- Brown JH. 1973. Toxicology and Pharmacology of Venoms from Poisonous Snakes. Springfield, Illinois: Charles C. Thomas. 184 pp. LCCCN 73-229. ISBN 0-398-02808-7.
- U.S. Navy. 1991. Poisonous Snakes of the World. New York: Dover Publications Inc. (United States Government Reprint). 203 pp. ISBN 0-486-26629-X.
- Ditmars RL. 1933. Reptiles of the World. Revised Edition. New York: The MacMillan Company. 329 pp. 89 plates.
- Photo sequence of Cerastes cerastes feeding in the wild (Gilf Kebir, Egypt, 27 October 2004) at FJ Expeditions accessed 19 October 2013
- Boulenger GA. 1896. Catalogue of the Snakes in the British Museum (Natural History). Volume III., Containing the...Viperidæ. London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiv + 727 pp. + Plates I.- XXV. (Cerastes cornutus, pp. 502–503).
- Calmette A. 1907. Les venins, les animaux venimeux et la serotherapie antivenimeuse. In: Bucherl W. editor. 1967. Venomous Animals and Their Venoms. Vol. I. Paris: Masson. 233 pp.
- Mohamed AH, Kamel A, Ayobe MH. 1969. "Studies of phospholipase A and B activities of Egyptian snake venoms and a scorpion venom". Toxicon 6: 293-988.
- Joger U. 1984. The Venomous Snakes of the Near and Middle East. Wiesbaden: Dr. Ludwig Reichert Verlag. 175 pp.
- Labib RS, Malim HY, Farag NW. 1979. "Fractionation of Cerastes cerastes and Cerastes vipera snake venoms by gel filtration and identification of some enzymatic and biological activities". Toxicon 17: 337-345.
- Labib RS, Azab MH, Farag NW. 1981. "Effects of Cerastes cerastes (Egyptian sand viper) snake venoms on blood coagulation: separation of coagulant and anticoagulant factors and their correlation with arginineesterase protease activities". Toxicon 19: 85-94.
- Labib RS, Azab ER, Farag NW. 1981. "Proteases of Cerastes cerastes and Cerastes vipera snake venoms". Toxicon 19: 73-83.
- Linnaeus C. 1758. Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, diferentiis, synonymis, locis. Tomus I. Editio Decima, Reformata. Stockholm: L. Salvius. 824 pp. (Coluber cerastes, p. 217).
- Schneemann M, Cathomas R, Laidlaw ST, El Nahas AM, Theakston RDG, Warrell DA. 2004. "Life-threatening envenoming by the Saharan horned viper (Cerastes cerastes) causing micro-angiopathic haemolysis, coagulopathy and acute renal failure: clinical cases and review". Association of Physicians. QJM 97 (11): 717-727. Full text at Oxford Journals. Accessed 9 March 2007.
- Schnurrenburger H. 1959. "Observations on behavior in two Libyan species of viperine snake". Herpetologica 15:70-2.
- U.S. Navy. 1991. Poisonous Snakes of the World. New York: Dover Books. (Reprint of United States Government Printing Office, Washington D.C.) 133 pp. ISBN 0-486-26629-X.
|Wikimedia Commons has media related to Cerastes cerastes.|
- Cerastes cerastes at the Reptarium.cz Reptile Database. Accessed 2 August 2007.
- Exceptional photo sequence of Cerastes cerastes feeding in the wild at FJ Expeditions taken on 27 October 2004. Accessed 19 October 2013.
- Sand viper page at Plumed-serpent.com. Accessed 30 July 2006.
- on YouTube. Accessed 31 May 2007.