North Africa 



a long spinelike horn above the eye ; in some, however, 

 this is short or absent. Body form is typically viperine 

 with wide triangular head, thick body, and short tail 

 tapering abruptly behind vent. Top of head covered 

 with small scales ; subcaudals paired ; ventrals feebly 

 keeled ; 15 or more scales across top of head ; more than 

 130 ventrals. 



Ground color yellowish, pale gray, pinkish or pale 

 brown with rows of dark brown, blackish or bluish 

 spots that may fuse into crossbars ; below whitish, tip of 

 tail black. 



Average length 20 to 2~> inches; maximum about 30 

 inches. 



Distribtitidit: The Sahara region and Arabian Penin- 

 sula ; parts of the Middle East. 



Inhabits deserts where there are rock outcroppings 

 and fine sand, often in very arid places; however, oases 

 are not avoided. It usually hides in rodent holes and 

 under stones. 



Remarks: Chiefly active at night. Like many desert 

 snakes, it often uses the sidewinding type of locomo- 

 tion. When angered it rubs inflated loops of its body 

 together to make a rasping hiss as does the saw-scaled 

 viper (Echis). 



It is not a particularly bad tempered or dangerous 

 snake, although it is inclined to stand its ground if 

 disturbed. It causes some snakebite accidents, but fa- 

 talities are rare. Antivenin is produced by the Institut 

 Pasteur. Paris, and the Institut Pasteur d'Algerie, Al- 

 giers?. 



Sahara Sand Viper, Cerastes vipera (Linnaeus). 



Idcntificution : Very similar in aiipearance to the 

 de.sert horned viper except that the horns are absent; 

 9-13 scales across top of head; fewer than l.'iO ventrals. 



Color much as in the horned vijier but tending to be 

 more faded with spots less well defined ; tip of tail black 

 in female, light in male. 



Average length 13 to 18 inches ; maximum about 22 

 inches ; females larger than males. 



Distrihution: Eastern and central Sahara to Israel 

 in sandy desert. 



Remarks: Found only in tracts of fine loose sand into 

 whicli it buries itself when alarmed ; usually spends the 

 day buried in sand at the base of a shrub ; active at 

 night. In places where this viper is common, the 

 horned viper is rare or absent and vice versa. Care 

 should be taken to differentiate this snake from Echis 

 carinatus, a much more dangerous snake. 



It is not a very dangerous snake; the venom is small 

 in amount and not highly toxic. Antivenin is produced 

 by the Institut Pasteur, Paris, and by Behringwerke 

 ( Polyvalent ) . 



Israel. The other (E. carinatun) ranges from Ceylon 

 and southern India across western Asia and north Africa 

 southward into tropical Africa. Although neither at- 

 tains a length of 3 feet, they posses a highly toxic venom 

 and are responsible for many deaths. When disturbed 

 they characteristically inflate the body and produce a 

 liissing sound by rubbing the saw-edged laternal scales 

 against one another. This same pattern of behavior is 

 shown by the nonpoisonous egg-eating snakes Dasypeltis. 



Definition: Head broad, very distinct from narrow 

 neck ; canthus indistinct. Body cylindrical, moderately 

 slender ; tail short. 



Eyes moderate in size; pupils vertically elliptical. 



Head scales : A narrow supraocular sometimes pres- 

 ent ; otherwise crown covered with small scales, which 

 may be smooth or keeled. Rostral and nasals distinct. 

 Laterally, eye separated from labials by 1-4 rows of 

 small scales ; nasal in contact with rostral or separated 

 from it by a row of small .scales. 



Body .scales ; Dorsals keeled, with apical pits, lateral 

 scales smaller, with serrate keels, in 27-37 oblique rows 

 at niidbody. Ventrals rounded. 132-20,"; subcaudals sin- 

 gle. 21-.^.2. 



Saw-scoled Viper, Echis carinatus (Schneider). 



Idrniification: Head short and wide, snout blunt; 

 body moderately stout ; scales on top of head small, 

 keeled ; scales on side of body strongly oblique, the keels 

 with minute serratimis; subcaudals single. 



Color pale buff or tan to olive brown, chestnut or 

 reddish ; midline row of whitish spots ; sides with nar- 

 row undulating white line; top of head usually shows 

 light trident or arrowhead mark with 3 prongs directed 

 posteriorly and one anteriorly; belly white to pinkish 

 brown stippled witli dark gray. 



Average lengtli l."> to 20 inches; maximum about 32 

 inches ; sexes of about equal size. 





^■^f •-' 



VIPERIDAE: Genus £cfi;s Merrem, 1820. 



Saw-scaled vipcfs. 



Two species are recognized. One (B. coloraiiis) is 

 restricted to eastern Egypt, the Arabian I'eninsula, and 



Figure ,12. — Saw-scaled Viper, Echis carinatus. Typical 

 defensive po.se. Photo by New York Zoological Society. 



Dixtrihidion: Almost the entire Afro-Asian desert 

 belt from Morocco and Ghana to the southern provinces 

 of Russian Asia and drier parts of India and Ceylon. 



83 



