Revisiting historical diversity of sawfishes (Pristidae) in the Mediterranean Sea using natural history collections

Abstract

Sawfishes are highly threatened elasmobranchs, now locally extinct in many coastal areas worldwide. Global conservation efforts emphasize documenting historical shifts in species’ distribution and range. In the Mediterranean Sea, these historical reconstructions suggested the past presence of two species, Pristis pristis and Pristis pectinata, thought extinct by the 1970s, revising prior assumptions on sawfish distribution. In this study, we evaluated whether any historical sawfish specimens housed in several European institutions and private collections might represent records from the Mediterranean Sea. We analysed 229 rostra, of which 28 were labelled as Mediterranean individuals. Most specimens lacked detailed taxonomic identification or reliable collection data. Using morphometrics and mitochondrial gene sequencing (partial COI and NADH2) we identified all rostra as belonging to four extant sawfish species: Pristis zijsron (104), Anoxypristis cuspidata (52), P. pristis (47), and P. pectinata (26). Specimens labelled as Mediterranean belonged to P. zijsron (9), A. cuspidata (8), P. pristis (6), and P. pectinata (5). These findings demonstrate the effectiveness of an integrative framework combining molecular and morphometric analyses for reliable species’ identification in historical sawfish specimens, providing a robust basis for re-evaluating historical diversity and biogeography even when collection metadata are incomplete or uncertain.