Cerastes cerastes
Cerastes cerastes, commonly known as the Saharan horned viper or the desert horned viper, is a venomous species of viper native to the deserts of northern Africa and parts of the Arabian Peninsula and Levant. It often is easily recognized by the presence of a pair of supraocular "horns", although hornless individuals do occur. Three subspecies have been described. Description. The average total length (body and tail) is , with a maximum total length of . 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, which 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. Common names of this species include desert sidewinding horned viper, Saharan horned viper, horned s, 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" (); in Libya, it is called "um-Goron" (). Distribution and habitat. The snake is common in Iraq but is also found in Syria, Saudi Arabia , Yemen, Jordan, Israel and Kuwait. They can also be found in parts of North Africa including Libya, Egypt, and Sudan. A report of the horned viper being found in Lebanon is unlikely, according to Joger (1984). A member of this species was reportedly found and killed by locals on the border between the Peshawar and Nowshera districts of Khyber Pakhtunkhwa province of Pakistan. The incident was reported along with a photo of the dead reptile in 'Aaj', and Urdu-language newspaper published in the provincial capital Peshawar on September 10, 2019. Originally, the type locality was listed only as "Oriente ." However, Flower (1933) proposed "Egypt" by way of clarification. These snakes favor dry, sandy areas with sparse rock outcroppings, and tend to avoid coarse sand. Occasionally they are found around oases, and up to an altitude of . Cooler temperatures, with annual averages of 20 °C or less, are preferred. Behavior. 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. Reproduction. 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. Venom. "Cerastes cerastes" venom 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 values of 0.4 mg/kg IV and 3.0 mg/kg SC. An estimated lethal dose for humans is 40–50 mg. Taxonomy. A number of subspecies have been described: Previously, "C. gasperettii" was also regarded as a subspecies of "C. cerastes".