Notes on a geologically young record of the extinct whale barnacle, Coronula bifida Bronn, 1831 (Calabrian, central Italy)

Two fossil whale barnacle (Cirripedia: Coronulidae) specimens are here described from the Calabrian locality of Montalto, Pisa Province (Tuscany, central Italy). Based on both traditional and micro-CT-assisted observations, the studied specimens are assigned to the extinct coronuline species Coronula bifida. This, coupled with other records, evokes the persistence of C. bifida into the late Early Pleistocene, that is, until a time when the extant species Coronula diadema was already present in the Pacific Ocean. On the whole, the distributional data conf lict with previous hypotheses that regarded C. bifida and C. diadema as globally distributed chronospecies, instead suggesting that the latter taxon may have originated from the former through cladogenesis. The specific kind of cetacean that hosted C. bifida during the Early Pleistocene is still unknown, but it may be found within the baleen whale family Balaenopteridae (humpback whales and rorquals).