Late Pleistocene Fish Remains from the Rurubu River, Tanzania

ABSTRACT

A collection of fish bones was recovered from upper Pleistocene (Gamblian) deposits near the confluence of the Kagera and Rurubu rivers in Tanzania, west of Lake Victoria. The Rurubu/Kagera bones include two families: the Clariidae (Clarias gariepinus, Clarias sp.) and Cichlidae (tribes Oreochromini, Haplochromini; Oreochromis sp.). Geological, paleontological, and molecular data presented here provide new insights into Pleistocene eastern African biogeography and into the evolution and past affiliations of the Rurubu/Kagera and Lake Victoria fish taxa. The data indicate that the Rurubu/Kagera taxa were descended from Miocene-aged populations in the Congo and/or Nile rivers. Data also suggest that the Rurubu/Kagera haplochromines may have been part of a shared Kagera River/Lake Victoria basin haplochromine clade, whose later members radiated into hundreds of species in Lake Victoria over the past approximately 15,000 years.

ACKNOWLEDGMENTS

The authors are grateful to M. Sinitsa (Yekaterinburg, Russia) for the collection of abandoned fish fossils from the Rurubu/Kagera and for bringing them to the authors’ attention. The authors also thank the editor, A. Murray, and one anonymous reviewer for their constructive and insightful comments. O.A.G.’s and N.V.P.’s contribution was made possible by Act 211 of the Government of the Russian Federation, contract no. 02.A03.21.0006.

ORCID

Kathlyn M. Stewart http://orcid.org/0000-0002-6259-6706

Oleksandr M. Kovalchuk http://orcid.org/0000-0002-9545-208X

Nataliya V. Pogodina http://orcid.org/0000-0003-1636-7010