Rolf Nussbaumer / Western Cottonmouth (Agkistrodon piscivorus leucostoma) head portrait in grass, Fennessey Ranch, Refugio, Coastal Bend, Texas Coast, USA

Edwin Giesbers / Portrait of female Adder (Vipera berus) in long grass, the Netherlands

Paul Hobson / Grass snake (Natrix natrix) swimming amongst duck weed, Oxfordshire, UK

Edwin Giesbers / Shed skin of grass snake {Natrix natrix} on lilypad, Netherlands.

Edwin Giesbers / Grass snake {Natrix natrix} coiled, the Netherlands

Kim Taylor / Grass Snake (Natrix natrix) captive, Surrey, England

Andy Sands / Grass snake (Natrix natrix) basking on tree stump among Bluebells, Hertfordshire, England. UK

Andy Sands / Grass snake (Natrix natrix) feigning death, Hertfordshire, England. UK

Solvin Zankl / Grass Snake (Natrix natrix) beside Marsh marigold flower in riverine habitat, Germany

Tony Phelps / Grass snake {Natrix natrix} male with eyes glazed prior to moulting, Surrey, UK

Andy Sands / Grass snake {Natrix natrix} swimming, Captive, UK

Tony Phelps / Grass snake feigning death {Natrix natrix} Purbeck, Dorset, UK