New mammal and bird tracks from the Lower Oligocene of the Ebro Basin (NE Spain): implications for the Palaeogene ichnological record

The Ebro Basin (Spain) is one of the few worldwide areas where Palaeogene avian and mammal tracksites have been found. A new unpublished tracksite known as La Sagarreta is here described. The tracksite is located in a sandstone-dominated outcrop from the Early Oligocene Peralta Formation in the northern-central sector of the basin. Six different ichnotaxa have been identified. Four belong to mammals, including perissodactyl (cf. <i>Plagiolophustipus</i> isp), artiodactyl (<i>Megapecoripeda</i> isp. and cf. <i>Pecoripeda</i> isp.) and carnivoramorph tracks (cf. <i>Canipeda</i> isp.), and the other two to avian tracks (<i>Aviadactyla vialovi</i> and <i>Gruipeda dominguensis</i>). La Sagarreta presents a high ichnodiversity with the presence of a medium-sized member likely of the genus <i>Plagiolophus</i> (or relative), one medium- and one small-sized artiodactyl that probably belong to the family Entelodontidae, one medium-size unidentified carnivorous mammal and two types of birds. La Sagarreta tracksite is the most diverse Early Oligocene tracksite of the Ebro Basin and one of the few palaeontologic vertebrate records at the central area of the basin during this age.