New carnivoraforms from the latest Paleocene of Europe and their bearing on the origin and radiation of Carnivoraformes (Carnivoramorpha, Mammalia)

ABSTRACT

We report the discovery of the earliest European carnivoraforms, based on two new taxa from the latest Paleocene of France and Romania. A new species of Vassacyon, V. prieuri, from the locality of Rivecourt (MP6b; Oise, France) (MP = Mammalian Paleogene reference levels) is described based on a dentary fragment and isolated teeth. This species displays several primitive features compared with species of Vassacyon known from the early Eocene of North America and Europe. A second Paleocene carnivoraform, cf. Gracilocyon sp., is described based on fragmentary specimens from the locality of Jibou (MP6b; Transylvania, Romania). Carnivoraformes were previously unknown in Europe before the Eocene, and Vassacyon prieuri and cf. Gracilocyon sp. are their oldest records in Europe. These discoveries favor the hypothesis of a dispersal of these two genera from Europe to North America during the Paleocene-Eocene Thermal Maximum. Vassacyon prieuri and cf. Gracilocyon sp. strengthen support for the level MP6b and its correlation with the Clarkforkian. The geographic origin of the Carnivoraformes remains unknown. However, based on the observed biochronological and geographic distributions of the carnivoraforms, we infer a possible Asian origin for this group. In this scenario, Gracilocyon and Vassacyon dispersed to Europe during the Clarkforkian MP6b time, probably together with rodent taxa, whereas Uintacyon dispersed from Asia to North America shortly after rodents and tillodonts.

http://zoobank.org/urn:lsid:zoobank.org:pub:FC885E7F-877A-4454-9902-DF118B8C8693

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Citation for this article: Solé, F., T. Smith, E. de Bast, V. Codrea, and E. Gheerbrant. 2016. New carnivoraforms from the latest Paleocene of Europe and their bearing on the origin and radiation of Carnivoraformes (Carnivoramorpha, Mammalia). Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2016.1082480.

ACKNOWLEDGMENTS

This paper is in honour of G. de Plöeg, J. Prieur, and C. Gagnaison, the French amateur palaeontologists who made the work at Rivecourt possible: without their tireless efforts and unselfish contributions to science, the early history of European carnivorous mammals would have stayed in the shadow of the past. Field work in Rivecourt has been possible thanks to permission and logistic support of F. Maubert, C. de Collasson, P. Lobjois, S. Rimey, and R. Maïa (Lafarge Granulats Company). Special thanks are addressed to C. Truffert (Research Division of the BRGM) for encouraging and supporting research on early Paleogene stratigraphy of the Paris Basin and E. Bas (CPIE) for promoting research on paleomammalogy in the Oise region. We would like to thank F. Vanderlinden (IRSNB) for his precious help with the sorting and preparation of the specimens from Rivecourt. We thank C. Iselin (Musée Antoine Vivenel) for the access to the specimens from Rivecourt. We also thank P. Gingerich (University of Michigan, Museum of Paleontology) for having authorized the illustration of UM 82530 (Vassacyon promicrodon). The research at Jibou (Romania) was financially supported by the National Geographic Society grant 7085-01 (E. Gheerbrant, V. Codrea). All participants in field work—too numerous to be named here—are acknowledged with thanks. We also thank the two anonymous referees and the editor, B. Van Valkenburgh, for their very constructive comments that improved the manuscript. This study was supported by a grant from ‘La Société des Amis du Muséum National d'Histoire Naturelle.’ This paper is a contribution to research project BR/121/A3/PALEURAFRICA, which is financially supported by the Belgian Science Policy Office.