First records of extinct kentriodontid and squalodelphinid dolphins from the Upper Marine Molasse (Burdigalian age) of Switzerland and a reappraisal of the Swiss cetacean fauna

• Published in: PeerJ
• Main Authors: Aguirre-Fernández, Gabriel, Jost, Jürg, Hilfiker, Sarah
• Other Authors: Fonds für Lehre und Forschung, The Synthesys Programme
• Format: Article in Journal/Newspaper
• Language: English
• Published: PeerJ 2022
• Subjects: Northwest Atlantic
• Online Access: http://dx.doi.org/10.7717/peerj.13251; https://peerj.com/articles/13251.pdf; https://peerj.com/articles/13251.xml; https://peerj.com/articles/13251.html

The Swiss Upper Marine Molasse (OMM) documents a transgression event dated to around 21 to 17 million years in which dolphin and other vertebrate remains have been reported. We revised the whole cetacean (whales and dolphins) OMM assemblage available in main collections, focusing on the identification and interpretation of periotics (bone that contains the inner ear). Periotics are rare, but they provide the richest taxonomic information in the sample and hint to environmental associations. Micro-computerized tomography allowed the reconstruction of bony labyrinths for comparisons and environmental interpretations. Three families are represented by periotics: Kentriodontidae, Squalodelphinidae and Physeteridae. The cetacean taxonomic composition of the Swiss OMM reinforces biogeographical patterns reported for the Mediterranean and Paratethys during the Burdigalian at a regional scale and the Calvert cetacean fauna of the northwest Atlantic at oceanic scale.