The phylogenetic relationships and species limits within the chiropteran family Miniopteridae are poorly known in mainland Africa. Recent systematic studies in Madagascar have shown that this is a species-rich family, yet only eight species are currently recognized or hypothesized for continental Africa. Based on partial cytochrome b sequences and morphometric analysis, we describe a new species of Miniopterus that is endemic to a restricted, montane region of Liberia and Guinea. Furthermore, the taxonomic status of the West African Miniopterus schreibersii villiersi is resolved and shown to be a distinct species, M. villiersi, that is not closely related to M. schreibersii. Finally, the species M. inflatus is revealed to be paraphyletic, with the central African rainforest populations apparently not closely related to the savanna forms in eastern and southern Africa. Based on the results of this study, the number of Miniopterus species in Africa has increased from eight to 11, with more cryptic species likely to be discovered.