Europe 



INTRODUCTION 



Europe has comparatively few species of native 

 snakes. This reflects the generally cool, present- 

 day climate, tlie scarcity of suital)le habitats for 

 snakes, and the geologic history of glaciation that 

 eliminated all reptiles from mucli of the continent 

 some 10,000 to 20,000 years ago. Poisonous 

 snakes in Europe tend to be quite local and spotty 

 in distribution, especially toward the north. The 

 hai'dwood and evergi'een forests that originally 

 covered much of the continent were never good 

 liabitats for snakes. Centuries of intensive agri- 

 culture and more recent industrialization have 

 furtlier reduced the suitable habitats. In spite 

 of tliis, i)oisonous snakes may be locally plentiful. 

 In Scandinavia and Finland, the European viper 

 ranges sliglitly above the Arctic Circle — farther 

 north than any other known species of snake. In 

 Finland during the sunnner of lOfi], Ifi.'? snake- 

 lutes were re[)orted. One physician in Corn- 

 wall, England, saw 18 cases of adder bite be- 

 I ween 1952 and ll)r)0. The eastern Mediterranean 

 region has the greatest number of venomous 

 snakes and the mo.st dangerous species. 



All the Eui'opean |>oisonous snakes are vipers 

 and present a strikingly similar appearance. 

 They are small to medium-sized snakes of mod- 

 erately stout build with shoi't tails. In distin- 

 guishing them from noni)oisonous snakes, note 

 that the eye is separated from the upper li}) 

 sliields by one or moiv small scales (exce])t in the 

 single species of pit viper Aghi-strodon Inifi/s) and 

 the pupil is elliptical. In most European non- 

 ])oisonous snakes the eye touches the u])i)er lip 

 shields and the ])upil is round. The only excep- 

 tions to both these rules are the little boas of the 



genus Eryx; they are easily recognized by their 

 small ventrals. In distinguishing one species of 



Map 



Soctifiii 4. Eiirii|io. 



viper from another, note particidarly the shape 

 of the snout and the presence or absence of en- 

 larged shields on the toj) of the head. Body 

 .scales are keeled in all the European vipers. 



The common vipers of Europe feed largely 

 U|)on lizards and small inannuals. They are all 

 live-bearing. 



Antivenins against venoms of the conunon 

 vipeis of Europe are pi'oihiced by the Institut 

 Pasteur, Paris; Behringwerke, MarburgLahn, 

 Germany; Institufo Sieroterai)ico e Vaccinogeno 

 Toscano, Siena, Italy; and the Institute for Ini- 

 nnuiology, Zagreb, Yugoslavia {Y'tpcra nmmo- 

 (lytcK only). 



KEY TO GENERA 



1. A. Nine large crown shields (fig. (>) ; eye in contact with 



upper lip shields 2 



B. Crown shields 6 or fewer or broken up into small scales; 



eye sejiarated from lip shields 3 



2. A. Loreal pit present (fig. 4) Agkktrodon 



B. Loreal pit absent NP* 



3. A. Ventrals extend full width of belly (fig. 9A) Vipeni 



B. Ventrals do not extend full width of belly (fig. 9B) XP 



• NP = Nonpolsonous 



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