A new species of Amphilagus (Mammalia: Lagomorpha) from the Late Oligocene lake deposits of Enspel (Westerwald, Germany)

Abstract

The Paleogene lagomorph record in Europe is based exclusively on dental remains-with the exception of an undetermined skeleton from the Late Oligocene oil shale locality of Rott, Germany (Paleogene Mammal Unit MP 30). The specimen described here was excavated from the Late Oligocene oil shales of the Enspel locality in the Westerwald, Germany. These crater lake deposits have an 40Ar/39Ar date of between 24.79 Ma and 24.56 Ma and are biostratigraphically correlated with MP 28. The specimen is preserved as a skull with an almost complete dentition and mandibles as well as an articulated partial skeleton with trunk and forelimbs. Based on the dentition, it can be safely attributed to the European early lagomorph Amphilagus and it is one of the oldest representatives of the genus. The cheek teeth are significantly larger than those of Amphilagus antiquus, the only species known from the European Paleogene. Therefore, we assign the Enspel lagomorph to a new species of Amphilagus. The Enspel specimen represents a juvenile individual based on the presence of almost unworn cheek teeth and a number of deciduous teeth. On the basis of the development of the dentition and skeletal elements, we estimate the individual age of the animal at about 5 weeks. Nevertheless, it is much larger than the Rott lagomorph, which also is a juvenile individual of approximately the same age, suggesting that the Rott lagomorph represents a taxon different from the Enspel Amphilagus. © 2009 Senckenberg, Gesellschaft für Naturforschung and Springer.