The last crocodylian in Central Europe? A new occurrence from the late Middle Miocene of the Vienna Basin (Austria)

We present a new record of a crocodylian osteoderm from the Middle Miocene (Sarmatian) of the Vienna Basin (Austria) and summarise the current knowledge of Sarmatian occurrences of crocodylians. Our data extend the stratigraphic range of crocodylians in Central Europe by about 1 my compared to previous estimates. The obvious decline of fossils in the late Middle Miocene deposits is discussed as a result of the strong reduction of wetland habitat during increased aridity, which in addition reduced fluvial transport of potential fossils into coastal marine depositional environments. Both factors resulted in considerable preservational bias and render it difficult to define the timing of the final extirpation of crocodylians from Central Europe. Other than a decline in temperature, increased seasonality during the late Middle Miocene might have been crucial for the retreat of these reptiles by extending the cool period during which the animals brumated.