Adder (vipera berus) male, close-up of head, tongue extended, peak district, uk

uk berus vertebrates britain snakes horizontals veperidae tongue blooded scaled animals adders serpentes horizontal limbless head adder scaly reptilia wildlife carnivorous male nature tongue united kingdom cold predator close up extended district english reptiles viperinae zoology serpent tongues vertebrate carnivore vipera reptile ophidia developed countries ectotherms british peak predatory developed country european england carnivora uk squamata ectotherm cold blooded carnivores snake serpents fauna ectothermic animal europe