Pupilla loessica LOŽEK 1954 (Gastropoda: Pulmonata: Pupillidae) - „A living Fossil“ in Central Asia?

Abstract

LOŽEK (1986) is of the opinion that Pupilla loessica has been found recently in Central Asia. The aim of this study is to provide some initial, concrete contributions to the discussion of this subject. It should be understood as a basis for further investigations. During recent visits on site between 1995 and 2006 in Central Asia in the Russian Altay, in Northern Mongolia, in the Baikal region and in the Tien Shan, numerous recent malacocenoses were examined. In many places evidence was found of a form of Pupilla which had not previously been described from this region; its shell morphology cannot be distinguished from Pupilla loessica. Its distribution is concentrated in the strongly continental Khrebet Saylyugem in the South Eastern Altay. The probability of the occurrence of Pupilla loessica in Central Asia is supported, apart from the shell morphology criteria, by the preference of this species for more continental types of habitat with average annual temperatures markedly below 0° C and the corresponding accompanying fauna adapted to the cold, including e.g. Columella columella, Vertigo genesii, Vallonia tenuilabris, etc., which make these fauna easily comparable to the Pleistocene glacial associations of the Central European region.