Variation in the body coloration of 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. Note that dark coloration types prevail in the north and northeast of the range. Natrix natrix × N. tessellata hybrids are often characterized by a brownish coloration.