An updated dichotomous key to the snakes of Europe
This work presents an updated dichotomous key to all snake species of Europe, based on morpho- logical, morphometric and distributional characters. It gathers data from both the last dichotomous keys concerning European snake species and every following paper giving updates on taxonomic classification or the occurrence of new allochthonous species. The key includes 58 species of snakes (five of which are recent allochthonous and one is listed as “uncertain taxon”) distributed on the European territory, and photographic material for each species. The aim of this paper is to make the identification of all European snake species through a single manuscript more accessible, not only for the research field, but also for the citizen science, thus enhancing data collection and assist species conservation.