Abstract
A recent collection of African electric fish of the genus Petrocephalus from the Bangweulu-Mweru ecoregion of the Congo basin comprises two endemic species, Petrocephalus squalostoma (Boulenger, 1915), which was previously known only from its type specimens and another specimen, and a new species described herein as Petrocephalus frieli sp. nov. An exclusive set of morphological characters distinguishes P. frieli sp. nov. from P. squalostoma and all other species of Petrocephalus from the Congo basin. Petrocephalus frieli sp. nov. can further be distinguished from the East African Petrocephalus catostoma catostoma (Günther, 1866) in having only 12 circumpenduncular scales (versus 15/16 in P. c. catostoma). A molecular phylogenetic analysis confirms the distinctiveness of P. squalostoma and P. frieli sp. nov. among a sampling of 18 species of Petrocephalus. Previous reports of Petrocephalus simus Sauvage, 1879 from the Bangweulu-Mweru ecoregion probably represent misidentifications and the occurrence of P. c. catostoma is not confirmed.
Acknowledgements
Roger Bills, Alex D. Chilala and John P. Friel collected the Petrocephalus specimens in the Bangweulu-Mweru region with funding from The All Catfish Species Inventory (NSF DEB-0315963). I also thank John P. Friel and Charles Dardia (Cornell University Museum of Vertebrates, Ithaca, NY, USA) and Oliver Crimmen and James Maclaine (Natural History Museum, London, UK) for access to the collections under their care. The specimen photographs are credited to Roger Bills, John P. Sullivan, and © The Natural History Museum, London. I thank Bernd Kramer, Roger Bills, Paul Skelton and Michael Wink for providing a copy of their taxonomic revision of the Petrocephalus of East and South Africa, ahead of publication. This manuscript has greatly benefited from the comments of two anonymous reviewers and Louise Allcock (co-editor, Journal of Natural History). This work was completed while I was at the National Taiwan University, supported by a postdoctoral fellowship from the National Science Council of Taiwan (NSC100-2811-M-002-069).