There is a group of snakes that are known as Pit Vipers. Not only are these snakes venomous they also have a very 'cool' heat sensing system. This helps these snakes to find prey in the dark, which is when most snakes like to hunt. The ‘pit’ is a special organ in between the eyes and the nostrils. The pit senses body heat from animals and gives the snake a ‘picture’ of that animal. The snake can then attack it. Some pit vipers will bite and poison the prey and then release it. It will follow the dying animal, using its heat sensors, until it stops and the snake can swallow it. Most pit vipers hunt at night when the air is cooler and the heat from rodents and other prey is most obvious to them. The ‘heat picture’ from larger animals will tell the snake that a quick escape is a good idea, too!
All rattlesnakes are Pit Vipers. Water Moccasins, Horned Desert Viper, Lance-head, Eyelash Viper, and the Copperhead are a few other examples of pit vipers.
The Desert Horned Viper
by Jay Sharp
The Desert Horned Viper – with its anvil-shaped head, satanic horns and cat-like eyes – has struck a chord in the imagination of those who have lived within its desert ranges, from northern Africa into the Middle East. For example, the snake played a prominent, and sometimes mystical, role in the history of the Egyptians, who embalmed Desert Horned Viper bodies, according to the Greek historian Herodotus. (The snake’s mummies have been discovered at the ancient city of Thebes, on the banks of the Nile River.) The snake’s icon stands for the phonetic sound “f” or “fy” in Egyptian hieroglyphics. A Desert Horned Viper may have been the species that inflicted Cleopatra’s fatal wound when that legendary woman used a serpent to commit suicide in the year 31 B. C., despairing over the imminent Roman conquest of her beloved land (an act immortalized by Shakespeare in Anthony and Cleopatra).
The Desert Horned Viper ranks as the most abundant and distinctive venomous snake within its range:
- Size and shape: Typically just under two feet in length, robust and cylindrically depressed body, narrow neck, thick midsection, tapering tail.
- Head: Broad, flat and round-snouted, with center-ridged (or keeled) scales; forward-set moderately large eyes with vertical pupils (much like those of the Southwestern rattlesnakes); distinctive supraorbital horns (which may not always be present in all populations or even individuals); hinged hollow fangs that snap into a biting position when the snake opens its mouth.
- Color and pattern: Yellowish, brownish, reddish to grayish colors, often matching the color of the surface of the soil; darker and more or less rectangular patches along the back.
The Bite, the Venom, the Consequences
The Desert Horned Viper can deliver a bite that – while not usually fatal – can have serious consequences. The venom, according to a report published in the Oxford Journal of Medicine, has more than 13 different toxins—a witch’s brew of poisons that may vary in mix by geographical location within the reptile’s range. It causes conditions such as massive local swelling, acute pain, excessive bleeding (or clotting, depending on the blend of toxins), nausea, abdominal pain, sweating, exhaustion, kidney failure and heart irregularities. (Reportedly, the snake took a toll on French Foreign Legionnaires when those troopers occupied Algeria.)
Writer Peter David Fraser claimed that the toxins could also inflict mental disorders, severe headaches, paralyzed facial muscles, imagined evil smells and other “peculiar sensations.”
Clinical study, said the Oxford Journal, “has demonstrated the ability of C. cerastes to cause complicated and potentially fatal envenoming…”
Range and Habitat
The snake’s range essentially spans the Sahara Desert, from Morocco and Mauritania on the western side of the African continent to Egypt and Sudan on the eastern side. It also occurs in the southern reaches of the Arabian Peninsula. It prefers drier areas with finer and looser sands and occasional rock outcrops, especially at higher elevations with less harsh desert temperatures.
The Desert Horned Viper – like all snakes, a meat eater – preys primarily on lizards but also on mammals and birds that inhabit its arid environment. It often lies in ambush, just beneath the sand with only its horns and eyes exposed, poised to explode from its cover and strike its victim with stunning swiftness.
Behavior and Life Cycle
Most active at night, the snake spends its days sequestered in the sand or in abandoned burrows or beneath rocky outcrops.
As it moves across the fine, loose sand of its habitat, the snake travels by “sidewinding,” or sliding sideways, much like the Sidewinder Rattlesnake of the Mojave and Sonoran Deserts of the American Southwest. In its sidewinding journey, the snake "looks something like a rolling spring and faces at an angle to its actual direction of travel: it appears to be headed in one direction while it is actually going in another," according to The Encyclopedia of Reptiles and Amphibians. Its unconventional method of locomotion notwithstanding, the Desert Horned Viper “moves randomly over a large area” according to Snakes: A Natural History, edited by Roland Bauchot.
It buries itself by shimmying its body into the fine loose sand, which it uses not only as a cover for ambushing prey and protection from the midday sun but also as its setting for copulation.
After mating, in the spring of the year, the female lays roughly a dozen to two dozen eggs in abandoned rodent burrows or beneath rock ledges. (She may have stored the sperm in her body for several weeks before she lays her eggs, said Dustin S. Siegel and David M. Sever in the paper “Utero-Muscular Twisting and Sperm Storage in Viperids.”) Once she lays her eggs, they hatch after 50 to 80 days of incubation. The new hatchlings will average four to six inches in length. They become sexually mature in about two years. They may live for 10 to 15 years or more.
Although its desert ranges rank among the world’s more harsh environments, the Desert Horned Viper has managed to sustain its numbers. As a species, it is not threatened. Among its enemies, however, are the large predatory birds and the Sand Cat (a small desert-adapted wild cat).
If threatened, the snake can produce a rasping warning sound, which it generates by rubbing together the obliquely-angled, saw-toothed scales along its flanks.
According to the Oxford Journal of Medicine, C. cerastes has two close relatives. One, the horned and similar-sized C. gasperettii, occupies a range extending from southern Israel eastward across Iraq into eastern Iran. The other, the hornless and much smaller C. vipera, shares much of the same range occupied by C. cerastes.
- The snake’s thorn-like horns comprise modified scales, said Chris Mattison, writing for The New Encyclopedia of Snakes. The horns have an uncertain biological function, although according to some naturalists, they may help protect the snake’s eyes in its sandy environment. The horns might also give the snake’s head an irregular silhouette, providing some measure of camouflage in the desert sand.
- If touched, the horns fold flush against the head, providing a streamlining that facilitates the snake’s passage through sand and burrows.
- The snake’s center-ridged, or keeled, scales trap early morning dew, providing at least a minimal source of fresh water, said Mark O’Shea in Venomous Snakes of the World.
- In some instances, the snake’s bite induces in its victim a sensation that the heart is being squeezed by a hand.
- The earliest known account of a treatment for the bite of the Desert Horned Viper, said the Oxford Journal of Medicine, dated from about 2200 years ago, when Egyptian physicians wrote that they believed that victims could usually be saved.
- This snake has a variety of other popular names, for instance: sahara horned viper, North African horned viper, African desert horned viper, horned desert viper, greater cerastes, asp, or simply, horned viper.
When, in Shakespeare’s immortal play, the clown delivered poisonous vipers to Cleopatra for her final act, he warned her, “…there is no goodness in the worm.” She held one to her breast and a second to her arm, allowing each of them to bite her. She died swiftly. At least in the play.
Read about more snakes:
DesertUSA is a comprehensive resource about the North American deserts and Southwest destinations. Learn about desert biomes while you discover how desert plants and animals learn to adapt to the harsh desert environment. Study desert landscapes and how the geologic features unique to the desert regions are formed. Find travel information about national parks, state parks, BLM land, and Southwest cities and towns located in or near the desert regions of the United States. Access maps and information about the Sonoran Desert, Mojave Desert, Great Basin Desert, and Chihuahuan Desert, which lie in the geographic regions of Arizona, California, New Mexico, Nevada, Texas, and Utah in the United States and into Mexico.
SEARCH THIS SITE
View Video about The Black Widow Spider. The female black widow spider is the most venomous spider in North America, but it seldom causes death to humans, because it only injects a very small amount of poison when it bites. Click here to view video.
Despite its pussycat appearance when seen in repose, the bobcat is quite fierce and is equipped to kill animals as large as deer. However, food habit studies have shown bobcats subsist on a diet of rabbits, ground squirrels, mice, pocket gophers and wood rats. Join us as we watch this sleepy bobcat show his teeth.
The Mountain Lion
The Mountain Lion, also known as the Cougar, Panther or Puma, is the most widely distributed cat in the Americas. It is unspotted -- tawny-colored above overlaid with buff below. It has a small head and small, rounded, black-tipped ears. Watch one in this video.
Take a look at our Animals index page to find information about all kinds of birds, snakes, mammals, spiders and more!
Click here to see current desert temperatures!
DesertUSA is a comprehensive resource about the North American deserts and Southwest destinations. Learn about desert biomes while you discover how desert plants and animals learn to adapt to the harsh desert environment. Find travel information about national parks, state parks, BLM land, and Southwest cities and towns located in or near the desert regions of the United States. Access maps and information about the Sonoran Desert, Mojave Desert, Great Basin Desert, and Chihuahuan Desert.