Late Pleistocene malacofauna of (MIS-2–MIS-4) loess-palaeosol sequence in Zalesie near Przemyśl (southern Poland)

Abstract

Lithological and malacological analysis was carried out at the loess site in Zalesie near Przemyśl. The profile exposed here comprises a loess-palaeosol sequence L-1 and is correlated with the Pleniglacial (MIS-2–MIS-4) of the Weichselian glaciation. Three loess layers separated by interstadial palaeosols are recognised here. Within the two younger parts of the cover, corresponding to the younger middle loess (LMs) and the younger upper loess (LMg), and in the soil horizon (Gi/LMs) separating them, numerous mollusc shells were found. The diversity of the malacofauna allowed five types of faunal assemblages to be distinguished. The main faunal components in the younger middle loess were open-country species typical of the dry subarctic steppe. The interstadial palaeosol horizon developed on this loess was dominated by hygrophilous taxa characteristic of the subarctic tundra environment. The malacofauna of the youngest part of the loess bed (LMg) contained mainly mesophilous snails, indicating the presence of open but relatively humid biotopes. The profile in Zalesie belongs to a tiny group of loess sites in Poland with a complete malacological sequence preserved, covering both the younger upper and middle loesses and the palaeosol horizon separating them.