A new meiolaniform turtle from the Maastrichtian of Northern Patagonia, Argentina
Federico L. Agnolin, Mauro Aranciaga Rolando, Juliana Sterli, Nicolás R. Chimento, Fernando E. Novas, and Gonzalo L. Muñoz
Meiolaniformes are a group of chelonians including the famous horned-turtles Niolamia argentina (Patagonia) and Meiolania platyceps (Australia). In South America, the Late Cretaceous meiolaniforms are represented by two named taxa: Patagoniaemys gasparinae coming from Campanian–Maastrichtian beds of the La Colonia Formation, Chubut province, and Trapalcochelys sulcata from the Campanian–Maastrichtian beds of the Allen Formation, Río Negro Province. The aim of the present contribution is to describe a new meiolaniform chelonian coming from the Upper Cretaceous (Maastrichtian) Los Alamitos Formation, at Río Negro Province, Argentina. The material is represented by a partial basicranium, incomplete carapace and fragmentary postcranial bones (MPMIK 1839/P/33) belonging to a new species Patagoniaemys aeschyli. To this new species we refer all the material previously referred as indeterminate meiolaniid, meiolaniform and cf. Niolamia sp., coming from the same site and locality, and described by different authors since the 1980s. This new species differs from the type species P. gasparinae, particularly by the presence of longitudinal ridges in the nuchal bone. We also include brief comments about meiolaniform palaeobiogeography and the impact of K/Pg extinction event in Patagonian chelonians.
Key words: Testudinata, Meiolaniformes, Los Alamitos Formation, Maastrichtian, Cretaceous, Patagonia, Argentina.
Federico L. Agnolín [fedeagnolin@yahoo.com.ar, ORCID: https://orcid.org/0000-0001-5073-561X], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Avenida Ángel Gallardo 470, Buenos Aires C1405DJR, Argentina. Fundación de Historia Natural “Félix de Azara”, Universidad Maimónides, Hidalgo 775, C1405BDB Buenos Aires, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. Mauro Aranciaga Rolando [mauro.a_guido@hotmail.com, ORCID: https://orcid.org/0000-0002-0833-6866] and Gonzalo L. Muñoz [gonza_25_rnr@hotmail.com, ORCID: https://orcid.org/0009-0000-5041-1009], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Avenida Ángel Gallardo 470, Buenos Aires C1405DJR, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. Juliana Sterli [jsterli@mef.org.ar, ORCID: https://orcid.org/0000-0003-2942-5558], Museo Paleontológico Egidio Feruglio, Av. Fontana 140, 9100 Trelew, Chubut, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. Nicolás R. Chimento [nicochimento@hotmail.com, ORCID: https://orcid.org/0000-0002-6340-4358] (corresponding author), Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Avenida Ángel Gallardo 470, Buenos Aires C1405DJR, Argentina. Fundación de Historia Natural “Félix de Azara”. Museo de Ciencias Naturales y Arqueología “Prof. Manuel Almeida”. 25 de Mayo 533 (2820), Gualeguaychú, Entre Ríos, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. Fernando E. Novas [fernovas@yahoo.com.ar, ORCID: https://orcid.org/0000-0002-6901-8677], Fundación de Historia Natural “Félix de Azara”, Universidad Maimónides, Hidalgo 775, C1405BDB Buenos Aires, Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (for details please see creativecommons.org), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Full text (2,045.1 kB)