Taxonomic affinities of the enigmatic Prionogale breviceps, early Miocene, Kenya

Abstract

Prionogale breviceps is a tiny carnivorous mammal from the early Miocene of eastern Africa. Originally, specimens were interpreted as the adult morphology of the taxon. The dentition did not obviously align Prionogale with the carnivorous lineages present in Afro-Arabia during the early Miocene: Hyaenodonta and Carnivora. When Namasector was discovered in Namibia, the small taxa were placed together in Prionogalidae and aligned with Hyaenodonta. In this study, based on comparisons to hyaenodont specimens preserving deciduous dentition, the holotype of Prionogale is reinterpreted as preserving dP3 and dP4. Some of the lower dental specimens attributed to the taxon preserve dp4. The holotype of Namasector also preserves deciduous dental material. A phylogenetic analysis that includes deciduous dental characters for a broader sample of hyaenodonts resolved Prionogalidae as a clade. Understanding of the deciduous dentition of Prionogale allows future analyses to compare homologous morphology, and to explore the environmental factors that shaped carnivorous mammal evolution through the Miocene.

Keywords:

• Neogene
• Africa
• ontogeny
• phylogeny
• Creodonta
• Hyaenodonta
• carnivory

Acknowledgements

We dedicate this paper to the memory of mentor and colleague G. Gunnell. We thank M. Munguu, R. Nyaboke, J. Kibii, and F.K. Manthi for access to collections at the National Museums of Kenya. We thank C. Argot and G. Billet (Muséum National d’Histoire Naturelle, Paris), M. Brett-Surman (National Museum of Natural History, Washington, DC), P. Brewer (Natural History Museum, London), J. Chupasko (Museum of Comparative Zoology, Cambridge), L. Costeur (Naturhistorisches Museum, Basel), J. Cundiff (Museum of Comparative Zoology, Cambridge), J. Galkin (American Museum of Natural History, New York), G. Gunnell (DPC), M. Hellmund (Geiseltal Museum, Halle), J. Hooker (Natural History Museum, London), A. Lavrov (Paleontological Institute, Moscow), C. Norris (Yale Peabody Museum, New Haven), S. Pierce (Museum of Comparative Zoology, Cambridge), B. Sanders (University of Michigan, Ann Arbor), S. Schaal (Naturmuseum Senckenberg, Frankfurt am Main), A. Sileem (Cairo Geological Museum, Cairo), T. Smith (Institut royal des Sciences naturelles de Belgique, Brussels), F. Solé (Institut royal des Sciences naturelles de Belgique, Brussels), G. Rössner (BSPG), A. Vogal (Naturmuseum Senckenberg, Frankfurt am Main), E. Westwig (American Museum of Natural History, New York), N. Xijun (Institute for Vertebrate Paleontology and Paleoanthropology, Beijing), and R. Ziegler (Staatliches Museum für Naturkunde Stuttgart) for access to specimens used in comparative studies. This paper is a contribution to the REACHE collaborative network, and to the project BR/121/A3/PALEURAFRICA of the Belgian Science Policy Office.