Distribution of light back stripes in grass snakes based on iNaturalist records. Densely documented western part enlarged in bottom map. Small inset map (top) shows subspecies distribution according to Asztalos et al. (2021a): Natrix natrix natrix – yellow, N. n. vulgaris – red, N. n. moreotica – grey, N. n. scutata – green. Hybrid zones hatched. Back stripes are restricted to two regions, the Balkan Peninsula plus adjacent Central Europe and Transcaucasia plus northern Iran.

  Part of: Fritz U, Ihlow F (2022) Citizen Science, taxonomy and grass snakes: iNaturalist helps to clarify variation of coloration and pattern in Natrix natrix subspecies. Vertebrate Zoology 72: 533-549. https://doi.org/10.3897/vz.72.e87426