Abstract
In this contribution, we describe the external and internal morphology of a delphinid petrosal bone collected from Ahu Tahai, a burial site located on the Southwestern coast of Easter Island, at Hangaroa. We discuss the taxonomic attribution of this archaeological item and describe its internal structures based on µCT data, including the bony labyrinth and the nerve and vein patterns. Identification of the nerves exists lead us to relocate the identification of the foramen singulare in delphinid petrosals.