Vipera berus walser

Sindaco, Roberto & Razzetti, Edoardo, 2021, An updated check-list of Italian amphibians and reptiles, Natural History Sciences 8 (2), pp. 35-46 : 42

76 Vipera berus walser - Species status debated. Previously considered an isolated population of V. berus (Capra, 1954; Sindaco et al., 2006), according to the phylogeny by Ghielmi et al. (2016) V. walser seems surprisingly related to the Caucasian species of the V. ursinii complex. Speybroeck et al. (2020) consider premature the acceptance of the new species due to the possible existence of cito-nuclear discordance and tentatively regard it as a subspecies of Vipera berus . Freitas et al. (2020) consider V. walser a valid species (Boettger 1889). Doniol-Valcroze et al. (2021) confirm the cito-nuclear discordance suspected by Speybroeck et al. (2020). Therefore, following these authors, we consider V. walser as a subspecies of V. berus .