A "Leptosaurus" (Rhynchocephalia) from the Kimmeridgian of Schamhaupten, Bavaria

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The Rhynchocephalia are an ancient group belonging to the Lepidosauria, and are currently represented with a single genus. However, the clade was taxonomically and ecologically diverse during the Mesozoic. Understanding the evolution of Mesozoic rhynchocephalians is thus of greatest importance for our interpretation of the recent Tuatara and of the implications of this group for our understanding of the other group of lepidosaurs, the squamates. One of the most important fossil lagerstätten for Mesozoic rhynchocephalians are the Late Jurassic limestones of southern Germany: Not only is this group represented by several taxa in these deposits, but these taxa are known from complete skeletons, whereas many Mesozoic rhynchocephalians are known only from isolated remains, often jaws. Unfortunately, however, the taxonomy of the rhynchocepalians from these limestones is still problematic, and recent finds have usually been referred to one of the known taxa simply on the basis of general similarity. Thus, the only known rhynchocephalian from the Kimmeridgian locality of Schamhaupten has been referred to Leptosaurus pulchellus, although it shows several differences to this taxon, which might indicate that it represents a new species. In the framework of this project, we will therefore study and describe this specimen in detail and establish its taxonomic identity. The results will not only be of interest for our understanding of the faunal composition of Schamhaupten and the diversity of rhynchocephalians in the Late Jurassic limestones of southern Germany, but will also provide new information on the separation or possible synonymy of the genera Kallimodon and Leptosaurus and the species included in these genera.