The Miocene Keramidomys (Rodentia, Eomyidae) from the Sandelzhausen locality (Germany)

In this note the taxonomic position of the tiny eomyid genus Keramidomys (Hartenberger, 1967) from the Early/Middle Miocene boundary locality of Sandelzhausen in the Bavarian Upper Freshwater Molasse is reexamined. As the chronological dating of the Sandelzhausen fossil site has been modified in the past from formerly the Neogene mammal unit MN6 to now MN5 and thanks to new abundant material this rodent is compared with other European forms. It is shown that the Sandelzhausen eomyid must be called K. thaleri Hugueney & Mein, 1968 on the basis of several morphological dental differences from K. carpathicus Schaub & Zapfe, 1953. This rodent seems to be an immigrant from East Asia into Europe. Even if K. thaleri is known in many European localities, all correlated to MN5, it is always a rare element of European rodent faunas. Differentiation from K. carpathicus is not easy and requires a sufficiently large sample.