Caucasus subalpine viper - Vipera dinniki
Commonly named Dinnik’s viper, and Caucasus subalpine viper, Vipera (Pelias) dinniki (Viperidae) is a species endemic to the Caucasus , found in Russia, Georgia and Azerbaijan.
It is a highly polymorphic species, with different color morphs in same small populations. The body color ranges from monophonic bronze-green to citreous-yellow, orange, red, or silver-grey, with dark brown or black zigzag which often can be broken off to few separate patterns.
Some interesting facts of this subalpine viper are: (1) the ability of females to hibernate while pregnant; and (2) the ability to give birth a year after mating (as observed in captive specimens). The possible reproduction without males in high-mountain zones of the Greater Caucasus can reflect either parthenogenesis, or the protracted retention of viable sperm, or delayed development of the impregnated ovules (histological analyzes are required to resolve this question).
Remaining pregnant during hibernation and the possibility of giving birth without mating are unique aspects of the reproductive strategies of alpine snakes of the Caucasus, developed in the glacial period.
The Caucasus subalpine viper is a declining species with some populations near to extinction. It is listed as Vulnerable (VU) on the IUCN Red List, and in the Red Data books of the Russian Federation, Krasnodarsky Krai, and Adygea Republic.
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Photo credit: ©Larsa Darafeyenka