Paleoecology and paleoenvironment of the Early Cretaceous theropod-dominated ichnoassemblage of the Los Corrales del Pelejón tracksite, Teruel Province, Spain

Abstract

[EN]The earliest Cretaceous (mid-late Berriasian) tracksite Los Corrales del Pelejón is an important dinosaur trackway site in Teruel Province in Spain. The ichnoassemblage occurs in the Galve Formation (Galve sub-basin, Maestrazgo Basin) and comprises around 40 tracks assigned to theropods and ornithopods. In this paper, we undertake a paleoenvironmental analysis of the succession, which includes the overbank deposits of a fluvial environment, and discuss the implications of these findings for trackway preservation and orientation. The track-bearing unit is composed of fine- to very fine-grained, thinly bedded sandstone layers with wave ripples and traces of the Mermia ichnofacies, which were deposited as splay deposits within an ephemeral overbank pond. Two different theropod ichnotaxa (Megalosauripus cf. transjuranicus and Grallatoridae indet.) of three different size classes occur as small-, medium-, and large-sized tracks. The ornithopod tracks are classified as cf. Iguanodontipus isp. Five theropod trackways (M. cf. transjuranicus) show a bimodal orientation pattern with a similar orientation to NE-SW wave ripple crests, suggesting that these animals were walking parallel to the shoreline of the ephemeral overbank pond. Three of them walked in a similar subparallel orientation, but there is no evidence suggesting gregarious behavior as they have slightly different orientations and/or speed values. The Los Corrales del Pelejón site is an example of environmental influence on dinosaur behavior.