The new rare record of the late Oligocene lizards and amphisbaenians from Germany and its impact on our knowledge of the European terminal Palaeogene

Abstract

There have been only a few studies on squamates from the late Oligocene of Europe, resulting in significant gaps in our knowledge of the reptile faunas from the latest Paleogene. Here, we report on new late Oligocene fossil material from two German localities, Herrlingen 11 (MP 28) and Herrlingen 9 (MP 29). The material can be assigned to the following major clades: Iguanidae, Gekkota, Lacertidae, Amphisbaenia, and Anguimorpha. The iguanid material shows that this clade was much more widely distributed in the Oligocene of Europe than previously thought, and also represents the youngest known record of this clade for Eurasia and Africa, with the exception of Madagascar. Although very fragmentary, the gekkotan material appears to be more similar to early Miocene forms such as Euleptes or Gerandogekko, rather than to early Oligocene taxa like Cadurcogekko, as indicated by the small size and morphology. The resemblance of the gekkotan fossils to Miocene forms suggests potential faunal turnover prior to the Paleogene–Neogene transition. The amphisbaenian material is represented by several types; the first can be allocated to Blanidae based on tooth count and the presence of a small 4th and an enlarged 3rd tooth, which is a derived feature. The second type is attributed to Palaeoblanus. Other cranial material is assigned to Amphisbaenia indet. The lacertid material consists of several amblyodont forms such as Dracaenosaurus, Pseudeumeces and Mediolacerta, as typically seen in other Oligocene deposits from Europe, but also includes non-ambylodont taxa such as Plesiolacerta and an undetermined lacertid. Especially common among the material are anguimorphs, which are here represented by Ophisaurus and a form that appears identical to the French Oligocene taxon described as Dopasia coderetensis. Reinvestigation of the European Oligocene "Dopasia" (=Ophisaurus) shows that the taxa described as D. frayssensis and D. coderetensis are markedly different from the members of the clade Ophisaurus in the morphology of the posterior dentary region and that those taxa cannot be allocated to this genus. For this reason, we erected a new generic name: Ophisauromimus gen. nov. The composition of the Herrlingen fauna shows an interesting mix of ancient Paleogene and more modern Neogene faunal elements, while overall bearing many similarities to contemporaneous faunas from France.