1. Snakes of Medical Importance in India: Is the Concept of the “Big 4” Still Relevant and Useful? 
Ian D. Simpson, BSc DM, Robert L. Norris, MD 
Wilderness & Environmental Medicine 
Volume 18, Issue 1, Pages 2-9 (March 2007)
DOI: /06-WEME-CO-023R1.1
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2. Figure 1 The Russell's viper (Daboia russelii).
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3. Figure 2 The saw-scaled viper (Echis carinatus).
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4. Figure 3 The Indian or spectacled cobra (Naja naja).
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5. Figure 4 The common krait (Bungarus caeruleus).
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6. Figure 5 The hump-nosed pit viper (Hypnale hypnale).
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7. Figure 6
Comparison of the head scalation of Echis carinatus (a) compared to Hypnale hypnale (b). Note the multiple tiny scales running between the eyes in Echis compared to the large plates in Hypnale.
Wilderness & Environmental Medicine  , 2-9DOI: ( /06-WEME-CO-023R1.1)
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