The sawfish (Rhinopristiformes, Pristidae) rostrum displayed in the "Basilica Santuario del Carmine Maggiore" in Naples, Italy: A long story of legends and taxonomic errors

Although historically widespread in most of the shallow and warm waters of the world, the presence of sawfishes in the Mediterranean Sea is still a debated question. For some authors, they never inhabited this basin except as vagrants, while for other authors both Pristis pristis and Pristis pectinata were present in the Mediterranean Sea but were extirpated in the 1960s-1970s. The sawfish rostrum kept in the Basilica Santuario del Carmine Maggiore (Naples, Italy), and considered by some authors the first record of sawfish in the Mediterranean was studied using a combination of morphological, genetic, radiocarbon dating and histochemical staining methods to validate the taxonomic identification, estimate its age and assess its geographical origin. Results indicate that the rostrum does not belong to P. pristis as reported by previous authors, but instead possesses morphological and genetic characters typical of P. pectinata. In addition, the radiocarbon age shows that the rostrum is more recent than previously believed, dating it back to the mid-nineteenth century, and genetic and meristic results cast doubt on its presumed Mediterranean origin. This study demonstrates that historical records should always be critically evaluated before using them to draw any far-reaching conclusion about species' past ecology and/or biogeography, and that future studies using historical information and specimens should adopt an integrative taxonomy approach similar to the one used here.