Poisonous Snakes of ihe World 



UuMsi'ir-i vlpfi- Is vi-ry prollllc k'vIiik lilrtli to -0 In 

 t'lO yimiiK. As Is Inn- of nmny smiki-s, ttu> yoiiiiK iiii' 

 iiiort' irrltiit>li' than tlio iidiilts. 



Itusscll's vliHT Is a leailliiK caiiso of .snaki-bltt- accl- 

 tU'iits 111 India and Huriiia, l>iit tlit> case fatality rate Is 

 lowt-r (liaii ill Idtos by kralts, cubras and saw-scaled 

 vl|iers. The lethal diise nf KiisseU's viper venom for 

 man Is estimated al 10 70 im;. ; a lai'Ke snake yields l.'O 

 '-'."lO mtf. Anliveiilns are produced liy llie HetiiinKwcrke, 

 Marbnri;-I,a)in. (iermiiiiy : Central Uesearch Institule. 

 Kasaiili. India : IlatTkine Institute, Hombay. India : 

 Queen Saovablia Memorial Institute, IJannkok. 



CROTALIDAE: Genus Agkistrodon Beauvois, 1799. 

 Miiccasiiis ;iiul Asian pit vipcfs. 



Twelve species are recognized. Three of these are 

 in North and Centrai America; tlie otliers are in Asia, 

 Willi one siiecies. .1, htihi.i (I'aiias) ranKiiiK westward to 

 .southeastern Europe. The American copperhead (.'1. 

 contortrix) and the Eurasian maniushi and its relatives 

 (A. halDs) seldom inflict a serious bite but .1. aciitiis and 

 A. rhiiilit.itiima of soutlieastern Asia, as well as the 

 cottonmoiith (.1. i>ixcir(>rii.i) of the soutlieastern fiiited 

 States, are dangerous species (see p. 13G for de.scription 

 of .1. acKtim) . 



Definitiiin: Head broad, tlattcned, very distinct from 

 narrow neck ; a sharjily-distingui.shed canthus. Body 

 cylindrical or dejiressed, taiiered, 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 iirefrontals 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. rlioiloxltima only) 

 or keeled, with apical pits, in 17-27 nonoblique rows. 

 \'eiitrals 12.5-174 ; subcaudals single anteriorly or paired 

 throughout. 21-08. 



Malayan Pit Viper, Aghistrodon rhodostoma 

 (Boie). 



Identification: Head triangular, snout pointed, facial 

 pit present. The only Asian pit viper with large scales 

 on the crown and .smooth body scales. 



Middle of back reddish or purplish brown, sides paler 

 with dark speckling; series of dark brown crossbands, 

 narrow in midline, wider on sides, edged with white or 

 buff ; bell.v pinkish white mottled with brown ; top of 

 head dark brown, sides light pinkish brown, the colors 

 separated by a white stripe that passes just above the 

 eye. 



Average length 23 to 32 inches ; maximum about 40 

 inches. 



Distribution: Thailand, northern Malaysia, Cambo- 

 dia, Laos, Viet Nam, Java, Sumatra — apparently re- 

 quires climate with well-marked wet and dry seasons. 

 Frequents forests generally at low elevations ; common 

 on rubber plantations. 



/i'cm«rA»; .\ bad tempered snake, quick to strike If 

 illsliirbed. In iioiihcrii .Malaysia it causes approxi- 



Fku'ke !tO. Malayan I'it Vii)er, Aylcintrodon rliodo- 

 .stiinid. This smooth-scaled pit viper is the source of 

 many bites in southeast Asia. Photo by New York 

 Zoological Society. 



mately 700 snakebites annually with a death rate of 

 about 2 percent. Weeders and tapjiers on rubber es- 

 tates are most frequently bitten. The snake is remark- 

 ably sedentary and has often been found at the site of 

 an accident after several hours. 



This is another of the oviparous vipers. The eggs 

 are guarded by the female. Antivenin is produced by 

 the Institut Pasteur. Paris; the Institut Pasteur, Ban- 

 dung, Indonesia ; and Queen Saovabha Memorial Insti- 

 tute, Bangkok. 



Hump-nosed Viper, Agkistrodon hypnale (Mer- 

 reni ) . 



Identification: Of typical viperine build with stout 

 body and wide head with facial pit ; snout pointed and 

 turned up; large frontal and parietal shields but shields 

 of snout small and irregular. 



Grayish, heavily powdered or mottled with brown ; 

 double row of large dark spots ; belly yellowish or 

 brownish with dark mottling ; tip of tail reddish or 

 yellow. 



Average length 12 to 18 inches. 



f r 



Ijs-X 



/ 



Figure 91. — Hump-nosed Viper, Aghi.strodon hypnalc. 

 Photo by Edward H. Taylor (Preserved specimen). 



128 



