Nose-Horned Viper Vipera Ammodytes (Linnaeus, 1758) with Atypical Characters from Western Bulgaria

摘要

Two atypical individuals of nose-horned viper Vipera ammodytes (Linnaeus, 1758) were found in West Bulgaria. This part of the country falls into the range of the nominate subspecies V. a. ammodytes. Both specimens possess a yellow or yellow- greenish tail tips. However this is a typical trait of the other subspecies found in Bulgaria, V. a. montandoni which range rest outside of the territory from where the reported snakes come. The study of a different traits shows that one the specimens is close to the nominate subspecies but another one is not. We future discuss the possible reasons for the appearing of these atypical specimen. The atavistic traits display, possible human transfer or natural movement was taken into account.