Poisonous Snakts of tho Wot Id 



GENERIC AND SPECIES DESCRIPTIONS 



ELAPIDAE: Genui Micruroides Schmidt, 1928. 

 Ari/.oim ronil siiiiko. 



A silicic s|H'<it's. .1/. iiirysiiiilhiin ( Kciiiilcott ). Is rec- 

 ociilzod. It is round III thi> soiitliwcstcrii I'liitod States 

 iiiul uortliwcstiTii Mexico. It is ii small stiakc but is 

 I'uiisidcrt'd daiiKtTous (sec p. r>2). 



Definition: Mead small, not disliiKl finm nccU ; snout 

 rounded, no distinct caiitlius. Hody slender and elong- 

 ate, not tapered; tail short. 



Kyes small ; pupils round. 



Head scales: The usual !' on the crown. Lati'rally, 

 nasal in contact with single preocular. Venlrally, men- 

 tal .separated from anterior chin shields hy first infrala- 

 hials. 



Hody s<ales : Dorsal sinoodi. in l.""! nonohliqup rows 

 throughout body. Ventrals -O^'lVl; anal plate divided; 

 siilicaudals paired, H)-.'?2. 



Maxillary teeth : Two relatively large tubular fangs 

 followed, after an interspace, by 1-2 small teeth. 



licmarks : Differs from nonpoisonous snakes as Mi- 

 crurus does; differs from Micrurus in the solid black 

 head color which ends in a straight line across the 

 parietals, and in the teeth behind the fangs. 



ELAPIDAE: Genus Micrurus Wagler, 1824. 

 Amefican coriil snakes. 



About 40 species are currently recognized. They 

 range from North Carolina to Texas, and from Coahuila 

 and Sonora, Mexico, southward through Central and 

 South America to Bolivia and Argentina. Most are 

 small species but some attain lengths in excess of 4 feet. 

 All are dangerous. 



Definition: Head small, not distinct from neck; snout 

 rounded, no distinct canthus. Body elongate, slender, 

 not tapered ; tail short. 



Eyes small ; pupils round. 



Head scales : The usual 9 on the crown. Laterally, 

 nasal in contact with single preocular. Ventrally, men- 

 tal separated from anterior chin shields by first in- 

 fralabials. 



Body scales : Dorsals smooth, in 1.5 nonoblique rows 

 throughout body. Ventrals 177-412 ; anal plate divided 

 or entire; subcaudals 16-62, usually paired but more 

 than 50 percent single in some species. 



Maxillary teeth : Two relatively large tubular fangs 

 with indistinct grooves ; no other teeth on bone. 



Remarks : Nearly all coral snakes have color patterns 

 made up of complete rings of yellow (or white), black, 

 and usually red. 



Eastern Coral Snake, Micrurus fulviui (Linna- 

 eus). 



Identification : Head small ; body slender with little 

 taper ; tail short ; scales smooth with high gloss. 



End of snout black followed by broad yellow band 



across base ut head iiikI wide, black, neck ring. Hody 

 completely encircled hy black, yellow, and red rings — 

 the red and yrllow rinn-i tourhinf/. If the red and 

 black rings touch each oilier, if the end of tin? snout l.s 

 red, whitish, or speckle<l, and if the colors fall lo en- 

 circle the br)(ly, llie snake Is not a North American coral 

 snake (see plate II. lig. .">). These rulen arc not neecn- 

 mrily true in tmiiieal America. In the small Arizona 

 coral snake ( Micniriiidcn eiirysantliiin) the yellow head 

 band is followed hy a wide red neck ring (see flg. 25). 



.\verage length '_'.'{ to .'{2 inches; maximum 47 inches. 



DiKlritiution : Soudiern Cnited States from coastal 

 North Carolina to west Texas and into northeastern 

 Mexico at low elevations. Inhabits grassland and dry 

 open woods; soiiieliines found along streams; occasion- 

 ally in suburban areas. 



Ilemarkx: Very secretive but sometimes found in 

 the open during early or midmorning. Rather quiik in 

 its movements. When res( rained il elevates the tail 

 with the tip slightly curled and freijuently tries to bite. 



Venom of (his coral snake is very toxic but small in 

 (luantity. .Many biles seem to he ineffective. In a 

 recently reported .series of 20 cases, 10 showed little 

 or no evidence of poi.soning. However, of 6 that showed 

 definite signs of systemic envenomation, 4 died. A species 

 specific antivenin soon will be available from Wyeth 

 Laboratories. 



CROTALIDAE: Genus Agfeisfrodon Beaovois, 1799. 



Moccasins and Asian pit vipers. 



Twelve species are recognized. Three of these are in 

 North and Central America ; the others are in Asia, 

 with one species, A. halys (Pallas) ranging westward 

 to southeastern Europe. The American copperhead (A. 

 eontortrix) and the Eurasian niamushi and its relatives 

 (A. halys) seldom inflict a serious bite but A. acutus 

 and A. rhodostoina of southeastern Asia, as well as the 

 cottonmouth {A. piscivorus) of the southeastern United 

 States, are dangerous species. 



Definition : Head broad, flattened, very distinct from 

 narrow neck; a sharply-distinguished canthus. Body 

 cylindrical or dei)ressed, tapered, moderately stout to 

 .stout ; tail short to moderately long. 



Eyes moderate in size; pupils vertically elliptical. 



Head scales : The usual 9 on the crown in most 

 species ; internasals and prefrontals broken up Into 

 small scales in some Asian forms ; a pointed nasal ap- 

 pendage in some. Laterally, loreal pit separated from 

 labials or its anterior border formed by second supra- 

 labial. Loreal scale present or absent. 



Body scales: Dorsals smooth (in A. rhodostoma 

 only) or keeled, with apical pits, in 17-27 nonoblique 

 rows. Ventrals 12.5-174 ; subcaudals single anteriorly 

 or paired throughout, 21-68. 



American Copperhead, Aqlc'istrodon eontortrix 

 (Linnaeus). 



Identification: Head triangular; body moderately 

 stout ; facial pit present ; pupil elliptical ; most of sub- 

 caudals undivided. 



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