title: The rediscovery and redescription of the holotype of the Late Jurassic turtle Plesiochelys etalloni.
abstract: Plesiochelyidae are a major component of Late Jurassic shallow marine environments throughout Europe. However, the taxonomy of plesiochelyid turtles is rather confused. Over the years, many taxa have been synonymized with Plesiochelys etalloni, one of the first described species. However, the holotype of P. etalloni (and only specimen known from Lect, the type locality) was lost for more than 150 years. This specimen has been recently rediscovered in the collections of the Musée d'archéologie du Jura in Lons-le-Saunier, France. For the first time since its original description in 1857, the holotype of P. etalloni is redescribed and compared to relevant material. The taxonomic status of this taxon is revised accordingly. Based on the morphology of the newly rediscovered holotype and on a reassessment of specimens from Solothurn (Switzerland), the species P. solodurensis, P. sanctaeverenae and P. langii are synonymized with P. etalloni. Known skull-shell associations for P. etalloni are re-evaluated in light of the new morphological information available since the rediscovery of this holotype specimen. Finally, we confirm that Plesiochelys is represented by a single species in the Late Jurassic of the Jura Mountains.
authors.affiliation: Section d'archéologie et paléontologie, Office de la culture, République et Canton du Jura , Porrentruy , Switzerland ; UMR CNRS 7207 MNHN UPMC, Muséum national d'Histoire naturelle , Paris , France.
authors.forename: Jérémy
authors.initials: J
authors.lastname: Anquetin
authors.affiliation: Musée d'Archéologie du Jura, CCE René Rémond , Lons-le-Saunier , France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Deschamps
authors.affiliation: Institut des Sciences de l'Evolution de Montpellier , UMR 5554 CNRS , Montpellier , France.
authors.forename: Julien
authors.initials: J
authors.lastname: Claude
keywords: France; Kimmeridgian; Late Jurassic; Plesiochelyidae; Plesiochelys; Switzerland; Testudines; Tithonian