Petrocephalus Marcusen, 1854 (Osteoglossomorpha: Mormyridae) of the Bangweulu-Mweru ecoregion (Luapula River system, Congo basin), with the description of a new species

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.