Vertebrate paleobiodiversity of the Early Cretaceous (Berriasian) Angeac-Charente Lagerstätte (southwestern France): implications for continental faunal turnover at the J / K boundary Author Allain, Ronan Author Vullo, Romain Author Rozada, Lee Author Anquetin, Jérémy Author Bourgeais, Renaud Author Goedert, Jean Author Lasseron, Maxime Author Martin, Jeremy E. Author Pérez-García, Adán Author Fabrègues, Claire Peyre De Author Royo-Torres, Rafael Author Augier, Dominique Author Bailly, Gilles text Geodiversitas 2022 2022-07-21 44 25 683 752 journal article 107849 10.5252/geodiversitas2022v44a25 d0184974-bea3-4f97-a2f8-98887ec4f87e 1638-9395 6902033 urn:lsid:zoobank.org:pub:EA12DCB7-A5BE-4763-B805-25087EBD726D Hylaeochelys belli ? ( Mantell, 1844 ) ( Fig. 12 C-H) DESCRIPTION The third turtle taxon is represented by many isolated plates and one incomplete specimen discovered in 2018, consisting of parts of the plastron, some peripherals and both humeri ( Fig. 12 C-H). The shell bone surface is nearly smooth with shallow grooves, which clearly distinguishes this taxon from the two others previously described. The shell bones are relatively thin. The vertebral scutes are very wide and cover more than half of the costals laterally. The neurals are narrow and elongated, especially in the mid-posterior part of the carapace. The plastron bears a central plastral fontanelle. The mesoplastron is absent. The humerus shape is unremarkable and similar to that recently described in Late Jurassic thalassochelydians (e.g., Püntener et al. 2014 , 2017 ). Based on the available characters, this form is possibly closely related to the Early Cretaceous (Purbeck and Wealden of the United Kingdom ) thalassochelydian Hylaeochelys belli ( Lydekker 1889 ; Hirayama et al. 2000 ; Pérez-García 2012; Pérez-García & Ortega 2014; Anquetin & André 2020 ). Hylaeochelys belli is generally considered to be a freshwater turtle based on the sedimentary contexts of the localities in which it occurs ( Milner et al. 2012 ; Pérez-García & Ortega 2014; Anquetin & André 2020 ). Most of the Angeac-Charente material represents juveniles or sub-adults, which may suggest that the swampy environment was a rookery for this turtle.