Repartition et dynamisme des faunes de Lacertilia et d'Amphisbaenia dans l'Eocène Europe

Marc Augé

The composition of assemblages of lizards and Amphisbaenian from the European Eocene are described. At least ten lizard families are identified from the lower European Eocene levels. Eight are still recorded in the last level (Escamps) of the late Eocene. Agamid lizards (genus Tinosaurus) died out by the end of the lower Eocene and Varanid lizards (genus Saniwa) disappeared by the beginning of the late Eocene. Amphisbaenians are recorded throughout the Eocene in Europe. The lacertilian fossil record of Europe and North America show a high degree of faunal resemblance in the early Eocene, followed by a decrease during the later part of the epoch. The lacertilian and amphisbaenian faunas from the European Eocene are not subject to great variations during the period; this is in contrast with the mammal record at the same time. It is argued that the low metabolic rates and the ectothermy of lizards could explain those differences, along with the increasing insularity of the West European area during the late Eocene time.