New Fossils of Mellivora Benfieldi (Mammalia, Carnivora, Mustelidae) from Langebaanweg, ‘E’ Quarry (South Africa, Early Pliocene): Re-Evaluation of the African Neogene Mellivorines

ABSTRACT

We describe abundant new remains of the medium-sized mustelid Mellivora benfieldi from the early Pliocene site of Langebaanweg (South Africa). The specimens are from the Muishond Fontein Pelletal Phosphorite Member (MPPM) and the Langeberg Quartz Sand Member (LQSM). Novel dentognathic—upper dentition, alveolus for m2—and postcranial—humerus, metacarpal V, femur and calcaneus—information is provided. This sample enables us to review the taxonomic status of Mio–Pliocene African mellivorines. Mellivora benfieldi is distinguished from the middle–late Miocene ‘Eomellivora’ tugenensis from Ngorora Kenya by its smaller size, and a M1 protocone messially placed; from the late Miocene Howellictis valentini from Chad by greater dental size with more crowded lower premolars, and p3 with distal accessory cuspid; and from the late Miocene Erokomellivora lothagamensis from Kenya, by shorter p4 and buccolingually shorter m1 protoconid. It also differs from H. valentini and Er. lothagamensis in absence or residual presence of the m2 alveolus. We infer M. benfieldi was an opportunistic, medium-sized carnivoran with semifossorial abilities, comparable to its living relative Mellivora capensis. A cladistic analysis was performed and our phylogenetic results place M. benfieldi as the sister species of M. capensis. Mellivorini contains M. benfieldi, M. capensis, and H. valentini. Additionally, we also include Er. lothagamensis and the Indian Promellivora punjabiensis. We propose the creation of one new tribe within Mellivorinae: Eomellivorini (Eomellivora spp. + Ekorus). It shares a common ancestor with Mellivorini and is characterized by large size, a robust and sharp dentition, as well as a skeleton with cursorial adaptations.

ACKNOWLEDGMENTS

We would like to thank the following curators and collection managers for access to comparative material under their care: E. Westwig, J. Galkin, J. Meng, R. O’Leary, and A. Gishlick (AMNH), B. Patterson, W. Simpson, and K. Angielczyk (FMNH), M. March, J. Galindo, J. M. Robles, and D. Alba (ICP), K. Rauscher (IPUW), J. Kibii (KNM), E. López Errasquin (MNCN), U. B. Göhlich (NHMW), D. Kalthoff (NRM), J. O. R. Ebbestad and V. Berg-Madsen (PMU), S. Govender (SAM-PQL), J. Opperman (SAM-ZM), and D. Lunde (USNM). We are especially grateful to M. Pina (Kyoto University), who kindly provided us with photographs of Erokomellivora lothagamensis housed at KNM, S. Mayda (Ege University) for the photographs of Laphictis mustelinus from La Grive-Saint-Alban (France), Steinheim (Germany), and Erkertshofen 2 (Germany), as well as Dehmictis vorax from Wintershof-West (Germany), J. Morales (MNCN) for photographs of Ischyrictis zibethoides from Sansan (France), and M. Sotnikova (Russian Academy of Sciences Moscow) for photographs of the holotype of E. ursogulo from Grebeniki (Ukraine). We also thank G. Avery (SAM-PQL) for discussion on South African Pleistocene Mellivora capensis, L. Werdelin (NRM) for kindly allowing us to study the cast of the skull and postcranial bones of Ekorus ekakeran and J. Samuels (ETSU), for kindly sharing the raw database of postcranial measurements of carnivorans published in Samuels et al. (2013). This research received support for A.V. from the European Union’s Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 226506 (SYNTHESYS; SETAF- 3637). A.V. also received support from the American Museum of Natural History Collection Study Grant Program 2014, the U.S.C. School of Medicine (Columbia, South Carolina, U.S.A.), and a Visiting Scholarship from the Chicago Field Museum of Natural History (2016). The support of the DST-NFR Centre of Excellence in Palaeosciences (CoE-Pal) toward this research for A.V. (COE2018-09POST and COE2019-PD07) is hereby acknowledged. Opinions expressed, and conclusions arrived at, are those of the authors and are not necessarily to be attributed to the CoE. R.G. was funded through the NRF/AOP Grant (UID98834). The “Juan de la Cierva Formación” program (FJC2018-036669-I), from the Spanish Ministry of Science, Innovation, and Universities also funded AV. Finally, we are indebted to the editor M. Borth and the reviewers L. Werdelin and L. de Bonis for their useful comments and suggestions, which made meaningful improvements to the original manuscript.