For more than 80 years, Proconsul has held a pivotal position in interpretations of catarrhine evolution and hominoid diversification in East Africa. The majority of what we 'know' about Proconsul, however, derives from abundant younger fossils found at the Kisingiri localities on Rusinga and Mfangano Islands rather than from the smaller samples found at Koru-the locality of the type species, Proconsul africanus-and other Tinderet deposits. One outcome of this is seen in recent attempts to expand the genus "Ugandapithecus" (considered here a junior subjective synonym of Proconsul), wherein much of the Tinderet sample was referred to that genus based primarily on differentiating it from the Kisingiri specimens rather than from the type species, P.africanus. This and other recent taxonomic revisions to Proconsul prompted us to undertake a systematic review of dentognathic specimens attributed to this taxon. Results of our study underscore and extend the substantive distinction of Tinderet and Ugandan Proconsul (i.e., Proconsul sensu stricto) from the Kisingiri fossils, the latter recognized here as a new genus. Specimens of the new genus are readily distinguished from Proconsul sensu stricto by morphology preserved in the P.africanus holotype, but also in I1s, lower incisors, upper and lower canines, and especially mandibular characteristics. A number of these differences are more advanced among Kisingiri specimens in the direction of crown hominoids. Proconsul sensu stricto is characterized by a suite of unique features that strongly unite the included species as a clade. There have been decades of contentious debate over the phylogenetic placement of Proconsul (sensu lato), due in part to there being a mixture of primitive and more advanced morphology within the single genus. By recognizing two distinct clades that, in large part, segregate these character states, we believe that better phylogenetic resolution can be achieved.
Bibliographical noteFunding Information:
We thank many people and agencies that assisted with the development and completion of this project. This research was initiated as a result of funding from the Wenner-Gren Foundation and the Johns Hopkins School of Medicine to D.R. Begun in 1987–1989 and was renewed following research and travel generously funded by multiple Leakey Foundation grants to K. McNulty, National Science Foundation grants to K. McNulty ( 0852609 , 1241807 ), the McKnight Foundation , the University of Minnesota , the Lloyd A. Wilford Endowment, the Leverhulme Foundation, and the Turkana Basin Institute. J. Kelley gratefully acknowledges support from the Institute of Human Origins, Arizona State University . D.R. Begun also wishes to acknowledge the Alexander Humboldt Stiftung and NSERC for funding support. We are grateful to the National Museums of Kenya, the Uganda Museum, the Natural History Museum, and to Rose Mwanja, Ezra Musiime, Tom Mukhuyu, Samuel Muteti, James Yatich, and Mary Muungu for access to and assistance with specimens in their care. Many people provided assistance, comments, criticisms, insights, and suggestions on various aspects of this work, and we especially thank Holly Dunsworth, Will Harcourt-Smith, Tom Lehmann, Dan Peppe, Nicole Garrett, Kirsten Jenkins, Rutger Jansma, Susy Cote, Isaiah Nengo, Andrew Hill, and Brenda Benefit. K. McNulty acknowledges the evolutionary anthropology faculty and students at Durham University for their helpful comments on an early version of this manuscript, and for their gracious hospitality. We are likewise grateful to the anonymous reviewers, associate editor, and editor whose comments strengthened the paper. This manuscript is publication #1 supporting Research on East African Catarrhine and Hominoid Evolution (REACHE).
© 2015 Elsevier Ltd.
- Fossil ape