ABSTRACT
Tragulids are ruminant artiodactyls living today in two distinct areas in Central Africa (Hyemoschus) and South plus South east Asia (Moschiola, Tragulus). Their fossil record, however, is distributed much more widely including Europe. Yet, their palaeobiogeography and phylogeography is not fully understood. Taxonomy in need of revision, limited data and biochronological controversies hamper the reconstruction of the irevolutionary history. This study provides a taxonomic revision of tragulid faunas from late Early Miocene to early Middle Miocene sites at Napak (Uganda), which include the oldest known record on the African continent. Morphological and metrical characters of dentition supports the presence of ?Siamotragulus songhorensis in Iriri Member (ca. 20.5 Ma), Napak Member (ca. 20.5–19 Ma), and Akisim Member (ca.16 Ma). ?Siamotragulus aff. songhorensis, ?Siamotragulus n. sp., and ?Afrotragulus sp. are documented sporadically in the Iriri and Napak Member. Dorcabune iririensis and Dorcabune chappuisi as well as Dorcatherium pigotti and Dorcatherium n. sp. are recorded in the Napak Member . The results confirm the previously described successive appearance with ?S. songhorensis followed by Dorcatherium (now Dorcatherium and Dorcabune). However, our data suggest a higher diversity than previously thought, and accordingly we provide a partially alternative interpretation of the evolutionary history of Miocene African tragulids.
Acknowledgments
Special thanks go to DAAD for financial support, and Pro jet de Paléontologie de l’Afrique sub-saharienne (MEAE)-commission des fouilles. Gratitude goes to Uganda Palaeontology Expedition team led M. Pickford (Paris) and B. Senut (Paris) and the Uganda Museum for collecting of most of the material studied in this paper. We thank the Natural History Museum of Vienna (Austria) through Frank E. Zachos and Ursula Göhlich, who provided access to the mammal collection (extant and fossilised); National Museum of Kenya and staff (Job Kibii, Fredrick Manthi, Emma Ndiema, Jimmy Yatich) for allowing access to the published material, and the Principal Investigators of Rusinga Island (Kieran P. McNulty, Minnesota, USA; Thomas Lehmann, Frankfurt, Germany) for allowing access to unpublished material and help with literature; National History Museum of United Kingdom and staff (Spyridoula Pappa, Phillipa Brewer); Muséum National d’Histoire Naturelle of Paris (France) and staff (Brigitte Senut, Martin Pickford and Guillaume Billet); and the Natural History Museum of Madrid (Spain) and staff (Jorge Morales, Israel Sánchez) for permission to access material in their custody. We appreciate Manuela Schellenberger (SNSB) for taking some of the photographs as well as Carla J. Harper and Imelda Hausmann (both SNSB) who taught SM to use the digital microscope. Alexandre Lethiers (Sorbonne University) is appreciated for assisting in the technical drawing of the stratigraphic figure. Special thanks reach out to Rose M. Nkaale and Doreen Katusiime (Uganda Ministry of Tourism, Wildlife and Antiquities) who granted leave for SM to study, and thanks to all staff and friends (S. Besigye, R. Asiimwe, C. Ssebuyungo among others) at the Uganda Museum for help in the field. Heartfelt gratitude goes to SM’s mummy (C. Kyangwa) for the support and encouragement to her all through this study. Sincere gratitude is forwarded to M. Pickford, B. Senut, D. Gommery and Julius B. Lejju (Uganda Mbarara East African University) for providing support to SM in various capacities. Special thanks goes to M. Aiglstorfer, I.M. Sánchez, B. Mennecart, and an anonymous reviewer who greatly helped to improve the manuscript.
Disclosure statement
No potential conflict of interest was reported by the author(s).