Mexico and Central America 



Remarks : Nearly all coral snakes have color pat- 

 terns made up of comi)lete rings of yellow (or white), 

 black, and usually red. They differ from their non- 

 poisonous "mimics" in that the red color, when present, 

 is usually bordered by the yellow or white ; in the non- 

 poisonous kinds it is usually bordered in black. 



Atlantic Coral Snake, Micrurus diastema (Dume- 

 ril, Bihroii, and Diiincril). 



Identification : A coral snake with numerous narrow 

 black rings, which alternate with yellow and red rings. 

 Black rings not narrowed laterally, usually complete 

 below. Adults average 2 to 3 feet in length. 



Black rings narrowly edged with yellow, which is 

 .sometimes absent ; red rings of approximately the same 

 width ; red scales tipped with black. Black rings not 

 in triads, varying from 10 in Yucatan to as many as 60 

 on the body in the highlands of Guatemala. 



Ventrals 192-229 ; subcaudals S2-')~ : no supra-anal 

 tubercles. 



Distribution : Eastern Mexico southward through 

 Guatemala and British Honduras to Honduras. 



RcmarliS: This remarkably variable coral snake is 

 fairly constant in any one region and can usually be 

 distinguished by the irregular lilack spots in the red 

 rings. 



Broad-banded Coral Snake, M'wnirus distans 

 (Keimicott). 



Identification : A coral snake with broad red bands 

 and single narrow black bands. The head is mainly 

 black and the lips are yellow. Adults average 2 to .•? 

 feet in length; maximum length 42 1/4 inches. 



The body color is mainly red. the red scales not black- 

 tipped. There are 11-17 black rings on tlie body, the 

 rings on the sides may be slightly narrower, and .3-0 

 black rings on the tail. The crown of the head is black 

 back to the level of the eyes, but the lips are yellow 

 (or white) and there are spots of the light color on the 

 snout. 



Ventrals 208-233 ; subcaudals 3S-.")2. 



Distribution : Western Mexico from Sonora to Guer- 

 rero. 



Remarks: This c(U-al snake has a remarkable harm- 

 less mimic which inhabits the same region. The neo- 

 tropical milksnake, Lanipmpettis triangiiliim nelsoni 

 Blanchard, has the same broad red bands and narrow 

 black bands. However, as in most coral snake mimics, 

 the black bands occur in pairs — an occurrence never 

 found in coral snakes. 



Black-ringed Coral Snake, Mtrnirus iniparfifus 

 (Diinieril, Bibroit, and Dumeril). 



Identification : A coral snake with broad black rings 

 and numerous narrow white, yellow, or red (in Central 

 America ) rings between. Adults average about 24 In- 

 ches in length : occasional individuals may exceed 3 

 feet. 



Snout black, a broad red baud passing just behind 

 eye and covering posterior part of head. Body with 

 34-81 black rings separated by narrow, (usually) yellow 

 rings ; tail with 3-."» black rings and 2-."> red rings. 



Ventrals 197-310: subcaudals 26-34. 



Distrihutiiin: Rain forest areas from Nicaragua to 

 northern Venezuela and Peru. 



Remarks: The unusual coloration of this coral snake, 

 a red ring on the head and 2-5 others on the tail, is 

 distinctive. 



Black-banded Coral Snake, Micrurus nigrocinctus 

 (Girard). 



Identification : A coral snake with a black snout and 

 broad red bands alternating with single uniform black 

 rings, each separated from the other with relatively 

 narrow yellow or whitish rings. Adults average 2 to 3 

 feet in length ; occasional individuals may attain lengths 

 of over 4 feet. 



One of the coral snakes with 12-20 single black rings 

 on the body (3-7 on tail) which are narrowly edged 

 with yellow or whitish. Alternating red rings usually 

 nuich broader than black, but relative amounts of black, 

 yellow and red vary geographically. Snout black with 

 darker color extending back over frontal area in a 

 l)oint. A broad yellow band over posterior part of head 

 and a black ring on neck. Scales of red area often 

 tipped with black. 



Ventrals 188-240; subcaudals 31-00. Males have su- 

 I)ra-anal tubercles. 



Distribution: Lowland rain forest areas (up to an 

 altitude of about 4.000 feet) from southern Mexico 

 I Guerrero) southward through Central America to 

 northwestern Colombia. This is one of the most com- 

 mon species of coral snakes in the region. 



Remarks : Two fatal bites referrable to this species 

 are known from Costa Rica (S. A. Jlinton). No anti- 

 venin is produced for this species. 



CROTALIDAE: Genus Agic/sfrodon Beauvois, 1799. 

 Mofcasiii-s and Asian Pit vipefs. 



Twelve species are recognized. Three of the.se 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 (.4. 

 cotttortrix) and the Eurasian nianuishi and its relatives 

 (.1. Iialjis) seldom inflict a serious bite but A. acutus 

 and .4. rliodostoma of .southeastern Asia, as well as the 

 cottonmouth (.4. piscirorus) of the southeastern United 

 States, are dangerous species. 



Definition: Head broad, flattened, very distinct from 

 narrow neck; .a shari)ly-distinguished canthus. Body 

 cylindrical or depressed, 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 ; interuasals and prefrontals broken up into small 

 scales in some Asian forms ; a pointed nasal appendage 

 in some. Laterally, loreal pit separated from labials or 

 its anterior border formed by second supralabial. Lo- 

 real scale present or absent. 



Bodv scales: Dorsals smooth (in A. rliodostoma 



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