Vipera latifii (Reptilia, Serpentes, Viperidae) an Endangered Viper from Lar Valley, Iran, and Remarks on the Sympatric Herpetofauna

Abstract

Vipera latifii Mertens, Darevsky & Klemmer, a recently described viper from northern Iran, is in severe need of conservation. Its range is restricted to the unique, alpine Lar Valley, which in a few years will be used as a huge water reservoir. Observations on the biology of Vipera latifii are given. Sympatric amphibians and reptiles show ecotypic adaptations. * * * The Lar Valley is found immediately south of the Caspian Sea in the Alburz mountain range, which is a barrier between two climatically and geobotanically different regions. Most valleys in the mountain range face either the deciduous forests on the northern slopes characterized by high rainfall and dense vegetation or the dry and sparsely vegetated steppe habitats along the southern slopes of the mountains. The geographical isolation of the Lar Valley makes it unique. With the exception of the steep and narrow canyon through which the Lar River exits to the Caspian Sea, the valley is surrounded by high mountains and is essentially closed. There is a distinct difference in the composition of the herpetofauna in different valleys in the Alburz Mountains. Those opening toward the south are inhabited by dry habitat amphibian and reptilian communities that include Agrama a. agilis Oliver, Agama c. caucasica (Eichwald) and Eumeces schneideri princeps (Eichwald), whereas north facing valleys possess species typical for humid forests or lowland habitats such as Rana macrocnemis pseudodalmatina Eiselt & Schmidtler, Anguis fragilis colchicus Demidoff, Ophisaurus apodus (Pallas), Lacerta chlorogaster Boulenger, Lacerta strigata Eichwald, Natrix tesselata (Laurenti) and Agkistrodon halys caucasicus Nikolski. The Lar Valley is located at an elevation of 2000 to 4000 m and is characterized as high, alpine steppe (Zoharry 1973). In this zone some wide-ranging alpine amphibian and reptile species occur. Of these, Lacerta raddei defilippi (Camerano) and Vipera ursinii ebneri Knoepffler & Sochurek are restricted to alpine elevations, while e.g. Agama c. caucasica and Agkistrodon halys caucasicus also occur at lower elevations. Bufo v. cf. viridis Laurenti, Rana r. ridibunda Pallas and Natrix t. tesselata have a wide elevational range from the Caspian Sea to the Alburz Moutains. Vipera latifii is in much need of conservation. However, the lack of knowledge about its ecology makes it difficult to create a fruitful plan for protection. Therefore we consider it important to present information on the habitat and biology of the species. We also find it relevant to comment the herpetofauna, of the isolated Lar Valley particularly Bufo v. cf. viridis and Agkistrodon halys caucasicus, which clearly differ from conspecific populations outside of the valley.