Dating of Permian Pyrenean terrestrial record (NE Iberian Peninsula). Interbasinal tetrapod ichnology correlation

Abstract

The limited ichnological tetrapod record of the continental red bed succession of the Pyrenean Permian (NE Iberian Peninsula) is here largely expanded after new findings. The aim of the present work is to highlight the faunal diversity by analyzing the tetrapod footprints with 3D techniques (i.e., photogrammetry), as well as inferring paleoenvironmental conditions of the studied localities. The tetrapod ichnoassemblage is composed of Batrachichnus salamandroides, cf. B. salamandroides, Limnopus isp., Amphisauropus isp., cf. Ichniotherium cottae, I. sphaerodactylum, Dromopus isp., Varanopus curvidactylus, Hyloidichnus isp. and Dimetropus leisnerianus. These ichnotaxa suggest the presence of temnospondyl amphibians, basal amniotes such as seymouriamorphs and diadectomorphs, captorhinid eureptiles and synapsid pelycosaurs as potential trackmakers. Several invertebrate traces, dominated by Notostraca ichnites, are identified on the ichnoassemblage, while plant remains are very scarce. Trace fossils are yielded in two ichnoassociations corresponding to different sedimentary deposits, showing that the taxonomical composition of each association is subjected to the paleoenvironmental conditions. The first ichnoassociation is in meandering fluvial system deposits, while the second one is in unconfined runoff surfaces. In comparison with basins bear ing similar ichnoassemblages (from Central Pangea and Central Europe), the tentative age assignation is middle-late Early Permian. The proximity to the Pangea equatorial part and the unsuspected fossil richness situate the Pyrenean basin as an important region for the understanding of the Permian terrestrial fauna evolution and the potential establishment of paleobiogeographic patterns.Peer Reviewe