A well-preserved mandible of Amphiperatherium from the Middle Miocene fissure filling Petersbuch 39: one of the youngest records of Metatheria (Mammalia) from Germany

The karst system of the White Jura-δ of Petersbuch near Eichstatt (Germany, Franconian Alb) is famous for the abundance of fossil-enriched infillings (e.g., Bolliger & Rummel 1994). More than 120 distinct fossil faunas ranging from the Oligocene to the Pleistocene have been recovered from these fissure fillings. One of the poorly studied Middle Miocene faunas is Petersbuch 39. This infilling is noteworthy because it contains remains of several taxa rarely reported from elsewhere in Germany, including representatives of the genus Cricetodon and a large cricetid rodent, Lartetomys (=Mixocricetodon; review of the genus in preparation by the authors and colleagues; Rummel 1997, 2000). Moreover, Mlikovský (1998) described several fossils of owls (Strigidae), and later also added Strix edwardsi and Coturnix gallica (Mlikovský 2002) to the inventory. Szyndlar & Rage (2002) reported on the presence of the Oriental viper (Vipera sp.) from Petersbuch 39. This communication briefly describes and discusses a mandible of Amphiperatherium, one of the rarest taxa from Petersbuch 39. The fossil stems from a private collection that was recently acquired by the Bavarian State Collection for Palaeontology and Geology (SNSB-BSPG) in Munich, Germany (see Rossner 2012 for an overview). The fossil is a well-preserved left mandible (SNSBBSPG 2011 V 1; Fig. 1) that evidences the presence of a metatherian mammal in the assemblage. It shows the ascending ramus, but the apophysis of the angular process is slightly broken. All molars are in situ but the m1 is lingually damaged. Anteriorly to the m1 occur seven alveoli (a large one for the canine and six smaller ones for the double-rooted p1-p3), and the most anterior part of the bone is missing. The ventral margin of the horizontal ramus is con