Some insights on well-preserved Amphisauropus and Erpetopus trackways from the Eastern Collio Basin (Trentino-Alto Adige, NE Italy)

The finding of new tetrapod trackways from the eastern sectors of the Collio Basin, in Val Aperta (Trentino Alto-Adige) allows new interpretations on Early Permian tetrapod behavior. The footprints, recorded in a slab with a wavy surface produced by ripples, consist of a short but well-preserved trackway attributable to Amphisauropus kablikae (Geinitz & Deichmüller, 1882) and two parallel trackways, moving in the same direction, assigned to Erpetopus willistoni Moodie, 1929. A narrower trackway, of uncertain taxonomic affinity, was probably produced in subaqueous conditions. This kind of association is the first report from all the Trentino-Alto Adige region, pointing to environments with higher energies than those associated to the classic Collio Formation.