Asp Viper
Vipera aspis balcanicaBuresch et Zonkov, 1934
Order Squamata
Family Viperidae
Conservation status: in Bulgaria: Extinct EX. International: BeC-III.
General distribution. From Northeastern Spain in the east to the border between Italy and Slovenia; in the north the area includes France (without the northern quarter), the westernmost part of Southern Germany (it is probably already extinct there), Western Switzerland, in the south – the whole of continental Italy and Sicily. Four individuals are known collected at the end of the 19th and the beginning of the 20th century in the Balkan peninsula, far from the area described: one from Saraevo in Bosnia, a second one near Ripan in Serbia and another two from Bulgaria [1].
Distribution and abundance in Bulgaria. From the territory of the country only two individuals are known: one large female, collected on 20 July 1933 near the village of Nadezhden, Harmanli region, and another one, male, collected earlier, but without a registered locality and a date of finding. It was probably found in the mountainous regions of the country [2]. There are no data of the numbers of the species in the past. It is supposed that the four Balkan individuals are last remains of a larger distribution of the species in the past that was later ousted by the nose-horned viper (Vipera ammodytes) [2]. The Harmanli specimen is the type individual of the subspecies Vipera aspis balcanica Buresch et Zonkov, 1934.
Habitats. In the main part of the area: mainly sunny, rocky and stony places. In the Pyrenees it has been found at altitudes of up to 2 900 m, and in the Alps at altitudes of up to 3000 m [3].
Biology. It gives birth to from 4 to 8 young. It feeds on small mammals, lizards, etc. Found in the stomach of the Bulgarian male individual with an unknown location was a swallowed rodent: an underground vole whose distribution in Bulgaria is mainly in the mountains [2].
Similar species. It resembles the common viper (Vipera berus) but differs from it by the upward tilted edge of the muzzle; in the viper, the flat upper surface of the head is without an upward tilted edge.
Negative factors. Unknown. Probably, the reasons for the disappearance of the species from the Balkan peninsula are not of an anthropogenic nature.
Conservation measures. In Bulgaria – none. Included in the Bulgarian Red Data Book, 1985, in category EX.
References. 1. Buresch & Zonkow, 1934; 2. Buresch & Beschkov, 1965; 3. Saint Girons, 1997.
Author: Vladimir Beschkov
