Adder (Vipera berus). Adult male. Showing inverted 'V' pattern on rear of head, a means of species identification.

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Adder or Northern Viper (Vipera berus). Adult male. Showing vertical pupil, inverted 'V' on rear of head and keeled scales- all features useful in species identification.

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Size: 4992px × 3328px
Photo credit: © Joe Blossom / Alamy / Afripics
License: Licensed
Model Released: No

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