An overview of the fossil turtles from Sardinia (Italy)

ABSTRACT

We review in detail the published fossil record of turtles from Sardinia and, in addition, we document previously undescribed specimens for the first time. Among these undescribed specimens, is the oldest occurrence of Testudo hermanni on the island, from the Early Pleistocene of Monte Tuttavista. The turtle fossil record in Sardinia goes back to the Eocene and comprises 18 different taxa, pertaining to 6 lineages: Podocnemididae, Cheloniidae, Emydidae, Geoemydidae, Testudinidae, and Trionychidae. Remarkable is the occurrence of Eocene pleurodires, whose presence is in agreement with the Oligo-Miocene rifting of the Corso-Sardinian block. Interestingly, the fossil record provides evidence for the presence in the island of both Testudo hermanni and Emys orbicularis during the Pleistocene although according to molecular data the extant populations of these two taxa were introduced in recent times. Finally, a large ungual phalanx from the Middle–Late Pleistocene Monte San Giovanni bone breccia testifies the occurrence of a giant tortoise in the Quaternary terrestrial ecosystem of Sardinia.

KEYWORDS:

• Testudines
• taxonomy
• palaeobiogeography
• Cenozoic
• Italy

Acknowledgments

C. Dal Sasso (Museo Civico di Storia Naturale di Milano) and R. Sardella (Museo Universitario di Scienze della Terra, Sapienza Università di Roma) are thanked for information about the collections under their care. DZ was supported by grants P.O.R. Sardegna F.S.E. 2014-2020 - Asse III “Istruzione e Formazione, Obiettivo Tematico: 10, Obiettivo Specifico: 10.5” Azione dell’accordo di Partenariato: 10.5.12 “Avviso di chiamata per il finanziamento di Progetti di ricerca - Anno 2017” GLP was supported by the Università di Cagliari CAR Project, “Paleobiodiversità: strumento di base in biostratigrafia, in paleoecologia e nella valorizzazione dei beni culturali Geo-Paleontologici” GLG acknowledges funding from the Ulam Program of the Polish National Agency for Academic Exchange (PPN/ULM/2020/1/00022/U/00001) and Forschungskredit of the University of Zurich, Grant no. [FK-20-110]. Field work background for this study at Fiume Santo and Monte Tuttavista has been carried out under agreements between the “Soprintendenza Archeologia, Belle Arti e Paesaggio per le province di Sassari e Nuoro” and the Dipartimento di Scienze della Terra dell’Università degli Studi di Firenze, and have been supported by the University of Florence (Fondi di Ateneo to LR), the National Geographic Society (grant #7484-03 to LR), the RHOI program at University of Berkeley (project NSF-BCS-0321893 to LR). Samplings at Grotte di Is Zuddas have been carried out under agreements between the “Soprintendenza Archeologia, belle arti e paesaggio per la città metropolitana di Cagliari e le province di Oristano e Sud Sardegna” and the Dipartimento di Scienze Chimiche e Geologiche dell’Università degli Studi di Cagliari. We would like to thank reviewers A. Čerňanský, W.G. Joyce and À.H. Luján for comments that greatly improved the quality of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Geographic Society [#7484-03].