The black viper has long been considered a species of ordinary viper. However, with a more thorough study of the snake, it was isolated and named after the zoologist Nikolsky (Vipera nikolskii).
The black viper has a more slender physique than an ordinary one. The body reaches a length of 765 mm, the tail - 80 mm. Males are slightly smaller than females. The head is wide, large, clearly delimited from the neck and slightly flattened. The iris is black. Adult snakes are always black, as can be seen in the photo. The adder on the labrum can sometimes have white spots. The bottom of the tip of the tail of the snake is yellow-orange or yellow. Young individuals have a gray-brown color with a zigzag on the back of a brown color. By three years of life, the pattern disappears, the color becomes dark.
Black viper lives in the forest-steppe and steppe regions of the European part of Russia and Ukraine (left-bank). The snake is noted in the Voronezh, Tambov, Penza, Saratov regions. It is found in the Don River Valley and its basin. In the northeast, the habitat extends to the foothills of the Middle and Southern Urals.
Black viper usually adheres to broad-leaved forests and oak forests. In the summer, it can be found in glades, clearings and edges. It prefers floodplain landscapes of the rivers Crow, Dipper, Khoper, Don, Seversky Donets and Samara. Summer and wintering habitats appear to be the same. In the wet areas of 1 km² there are more than 500 species. The black viper begins to show activity closer to mid-spring. Mating takes place in May, and in August, the female appears young (8-24 live individuals). The color of young snakes begins to darken after the first molt.
Nikolsky's viper is most active in the daytime. The main food of the snake is small rodents and (to a lesser extent) birds, frogs and lizards. In rare cases (apparently, with an extreme shortage of food), the black viper can eat fish or carrion. The biology of this species is still not well understood.
The black viper, in comparison with the already snake-like snakes, moves more slowly, but swims very well. In dangerous situations, takes an s-shaped stance, hisses and lunges towards the offender. Nicholas viper is poisonous. For a person, her bites are very painful, but the victims recover in a few days. The poison is a mixture of protein substances, enzymes and inorganic components. It has a destructive effect on tissues, paralyzes the nervous system and promotes blood coagulation. Caught individuals secrete liquid with a repulsive unpleasant odor from the cesspool.
For a long time, this snake was considered a dark form of the viper ordinary, based on the fact that in all its populations there is a certain percentage of melanists. However, after a careful study of the ecology and morphology of this snake, it was given species status. This significantly increased the interest of specialists in its study. But opinions still differ. Some scientists continue to consider this snake as just a subspecies of the basic form.
