First fossils of the extant blacktip shark carcharhinus limbatus from europe and the mediterranean basin

Here we report on two fossil teeth attributed to the blacktip shark Carcharhinus limbatus (Elasmobranchii: Carcharhiniformes: Carcharhinidae) from lower Pliocene (ca. 5.1–4.5 Ma) marine deposits of Tuscany (central Italy). A survey of the palaeoichthyological literature and online resources reveals that fossils of C. limbatus have been reported from Neogene and Quaternary deposits of the Americas and Indo-Pacific Asia. Therefore, the Tuscan specimens described herein represent the first occurrence of C. limbatus as a fossil from both Europe and the Mediterranean Basin. Our finds suggest that the blacktip shark reached a circumglobal distribution in warm waters (including the then warmer-than-today Mediterranean Sea) not later than the Pliocene; at the same time, they demonstrate that the continued study of the relatively well-investigated Neogene elasmobranch faunas of Italy can still result in significant novelties. Further investigations on other shark tooth assemblages from shallow-marine, warm-water, nearshore deposits are likely to reveal new occurrences of C. limbatus in the Pliocene of the Mediterranean Sea and elsewhere (e.g., along the palaeontologically under-explored Atlantic and Pacific coasts of Africa).