Vipera eriwanensis (Reuss, 1933), known only from the localities of the eastern Aras River in Turkey, was morphologically examined and compared with the related species on the basis of one additional specimen from Gavur mountain (province Gümüşhane), situated outside the known localities. This information changed our knowledge of the total distribution of V. eriwanensis, clearly showing that this taxon has expanded its range at least 210 km to the west in eastern Turkey. Furthermore it differs from V. eriwanensis reported from Turkey, Armenia and Azerbaijan in having a lower number of mid-body scales and loreals, and a higher number of crown scales.
KUTRUP, BİLAL; BÜLBÜL, UFUK; and YILMAZ, NURHAYAT (2005) "On the Distribution and Morphology of the Steppe Viper, Vipera eriwanensis (REUSS, 1933), from Gavur Mountain (Gümüşhane)," Turkish Journal of Zoology: Vol. 29: No. 4, Article 6. Available at: https://journals.tubitak.gov.tr/zoology/vol29/iss4/6