The smooth snake is a non-venomous colubrid snake, which adopted the bad idea of resembling the venomous vipera aspis, which has led to it being killed indiscriminately. We must remember, however, that both the vipera aspis and the smooth snake are protected species. It can be recognised in particular by the black stripe over its eye and on its round pupil (which helps to distinguish colubrids from vipers, which have a slit pupil).