Since the late eighties, reptiles are receiving attention, because many populations are assumed to decline and many species are considered threatened (Christainsen 1981, Honegger 1981, McNeely 1992, Langton and Burton 1997, Gibbons et al. 2000, Reading et al. 2010, Todd et al. 2010, Böhm et al. 2013). During these years, research on the European herpetofauna increased greatly, especially focusing on distribution and conservation status (Sillero et al. 2014a). Based on the work of many local and national associations, which contributed significantly in filling distributional knowledge gaps (Jacob et al. 2007, Loureiro et al. 2008, Creemers et al. 2009, Corti et al. 2010), nowadays the current spatial distribution of European reptiles (and amphibians) is available online (Sillero et al. 2014a, b). According to this database, there are 145 species of reptiles in Europe, and almost 20% of them are considered threatened according to the Biodiversity Information System for Europe (BISE 2018). The majority of these threatened species are endemic to both Europe and the 27 European Union member states (EU 27), with particularly high endemism richness in the Iberian peninsula, in the Balkans and within Mediterranean islands (Cox and Temple 2009, Silva et al. 2009). Reptiles often show very specific habitat requirements and are particularly vulnerable to anthropogenic threats, so that they require urgent conservation measures (Böhm et al. 2013).