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We here describe the first Neogene record of the squamate clade Mabuyidae. Although this clade has a cosmopolitan distribution today, no pre‐Quaternary fossil record of these reptiles has so far been documented. The material comes from the locality Solnechnodolsk (Russia) and is dated to the late Miocene (MN 13). Although it comprises only jaw elements, it constitutes the first evidence of the occurrence of fossil skinks around the area of the Black Sea. The material is identical to Heremites vittatus, showing the existence of this lineage as early as the late Miocene. Thus, it may be used as a potential calibration point for further studies. The comparative anatomy of the structures of lower jaw in selected scincomorph taxa with a special reference to Mabuya group is presented. The closure of the Meckelian canal is the condition at the basal node of the clade Sphenomorphidae + Eugongylidae + Egerniidae + Mabuyidea, whereas the closed canal in Acontias (Acontidae) evolved independently. However, Sphenomorphidae (Asymblepharus and Scincella) + Eugongylidae (Ablepharus) retain a large anterior opening of the Meckelian canal, whereas only a small opening characterizes the basal node of Egerniidae and Mabuyidae, except for H. vittatus and H. septemtaeniatus. The closure of the Meckelian canal in these two taxa is less well developed in comparison with other mabuyid skinks. Thus, a heterochronic pedomorphic process might have played a role in the evolution of these skinks. The Meckelian canal condition supports the monophyly of Heremites. [ABSTRACT FROM AUTHOR]

The lacertid material from the locality of Herrlingen 8 (upper Oligocene, MP28) is described as a new species of the genus Plesiolacerta. The material is disarticulated and comprises isolated elements including parietal, frontal, maxilla and dentary. It can be assigned to a single species on the basis of the external surface ornamentation. This morphology is typical for the genus Plesiolacerta, but the material differs in detail from the type species P. lydekkeri. The most significant feature of the new species is that the occipital scute of the parietal bone is narrow, rectangular in shape and anteroposteriorly short. Hitherto, the last occurrence of this genus was in the lower Oligocene. This material represents the first evidence of the existence of this genus in the upper Oligocene. Therefore, our knowledge of its evolution is expanded by providing new data on its spatial and temporal ranges and morphology. This taxon has a much longer history than we thought. In addition, the Eocene species, P. lydekkeri, is reviewed here. P. lydekkeri shares the most lacertid synapomorphies and, given our present knowledge, Plesiolacerta is a taxon very close to or possibly within crown Lacertidae. The frontal and postorbitofrontal of Plesiolacerta are described for the first time. In view of the primitive morphology and early occurrence of Plesiolacerta, it seems that the feature of a longer anterior region of the frontal could be considered as a plesiomorphic feature within lacertid lizards, and the condition in Timon (approximately the same length) as derived. [ABSTRACT FROM AUTHOR]