The taxonomic history of the African catfish genus Auchenoglanis includes eight nominal species, with two of these, Auchenoglanis biscutatus and Auchenoglanis occidentalis, being recognized as valid by most authors. The validity of all eight species was recently established based on mainly pigmentation-related characters and the shape of the premaxillary tooth plates. As these results opposed previous works but lacked any mention of these, the species diversity in the genus was re-evaluated based on biometric, meristic and other morphological data. It reconfirms the status of only two valid species within the genus. Auchenoglanis occidentalis ranks among the African fish species with very large distribution areas, being present from Senegal to Tanzania. Auchenoglanis biscutatus is distinguished from A. occidentalis by a postorbital head length that is greater than the preorbital head length, an adipose fin that rises abruptly, and a maxillary barbel with a tip not darker than the head colour.