Middle-to-Late Pleistocene malacofauna from the archeopaleontological site of Oued Sarrat (Tajerouine area, NW Tunisia)

Abstract

The malacofauna collected from the archeopaleontological site in Oued Sarrat (Tajerouine area, NW Tunisia) is the first reference from the Middle and Late Pleistocene stratigraphic series in Tunisia. These malacologic assemblages are abundant but little diversified; they are considered as continental, lakeside, and fluviatile ecosystem forms. They are associated with bones of small and large vertebrates and lithic artifacts. The dominant species of gastropods are Cernuella virgata (Da Costa, 1778), Xerosecta cespitum (Draparnaud, 1801), and Sphincterochila baetica (Rossmassler, 1854) which are typical of the Mediterranean regions. The abundance of these pulmonate terrestrial gastropods indicates a post-mortem transport of shells by floods and fluvial channels. The only bivalve, Unio ravoisieri (Deshayes, 1847), still common in the rivers of northern Tunisia, characterizes a typical lakeside environment, with relatively low energy. Considering the recently discovered associated vertebrate remains, their occurrence corroborates the onset of a paleoenvironment landscape with swamps, or even a shallow freshwater paleolake with close forests. Hence, this environment also inhabited by a diversity of large mammal species and other abundant microvertebrates and invertebrates was a support for human survival within these northern African latitudes.