Vipera berus bosniensis

Vipera berus bosniensis, the Balkan cross adder or Bosnian viper, is a venomous subspecies of viper endemic to the Balkan Peninsula.

Geographic range
It is only found within the Balkan Peninsula, particularly the Herzegovina region of Bosnia and Herzegovina, hence its common name.

Taxonomy
McDiarmid et al. (1999) follow Golay et al. (1993) and recognize V. b. bosniensis as a subspecies of V. berus. However, it has been considered a full species in recent literature.