Fossil Record 24(1): 77-92, doi: 10.5194/fr-24-77-2021
A new delphinid from the lower Pliocene of the North Sea and the early radiations of true dolphins
expand article infoAlice Belluzzo, Olivier Lambert
‡ Dipartimento di Scienze della Terra, Università di Pisa, Pisa, Italy
Open Access

With a remarkable exception for the Mediterranean, the worldwidePliocene record of true dolphins (Cetacea, Odontoceti, Delphinidae) remainsscarce, in stark contrast with the large number of extant species testifyingto the evolutionary success of this family. Based on a fragmentary skulldiscovered in lower Pliocene deposits (Zanclean, 5 to 4.4 Ma) of theKattendijk Formation in the Antwerp harbour (Belgium, southern margin of theNorth Sea basin), we describe here a new delphinid species, Pliodelphis doelensis gen. et sp.nov. This small dolphin with cranial dimensions in the range of theshort-beaked common dolphin Delphinus delphis can be distinguished from other extinct andextant delphinids by a combination of cranial features including the maxillabeing significantly narrower than the premaxilla at a short distanceanterior to the antorbital notch in dorsal view, the maximum opening of themesorostral groove being located at the level of the antorbital notches, atransversely wide and anteroposteriorly long dorsal exposure of thepresphenoid anterior to the bony nares, and all dorsal infraorbital foraminabeing located posterior to the premaxillary foramina. P. doelensis constitutes the firstmember of the family described from the early Pliocene of the North Seabasin and, for the whole North Atlantic realm, only the third outside theMediterranean. This new record contributes thus to our understanding of thepoorly known Pliocene radiation(s) of true dolphins.