Genetic and Morphological Evidence From a Group of Rare African Free-Tailed Bats Reveals a New Subgenus Within Mops

Recent surveys in the Congolian rainforest have significantly improved the quantity and quality of material available to rigorously assess bat diversity (Order Chiroptera) in this biodiversity hotspot. However, the paucity of data on free-tailed bats in this region is hindering our ability to resolve the actual number of species present in Central Africa. During a recent expedition to continental Equatorial Guinea, a single free-tailed bat was captured in a patch of primary continental rainforest. This bat exhibited unique external and cranial characteristics, strongly suggesting it to be a male of Mops tomensis, which was originally described as an endemic species from the oceanic island São Tomé in the Gulf of Guinea. The original description of this species was based on just three females collected 30 years ago. DNA from a paratype of M. tomensis fully supported that the newly captured specimen represents the first documented male of the species and extends its known distribution to mainland Africa. Furthermore, genetic analyses revealed a high divergence between these two individuals of M. tomensis and other species of the genus, and both clustered within a distinct, well-supported clade. With this genetic evidence, along with the unique morphological features of M. tomensis-like the prominent interaural lobe that is shared only with one other enigmatic free-tailed bat from the Democratic Republic of the Congo (Mops gallagheri)-we describe a new subgenus within Mops, as previously suggested for M. gallagheri. These findings demonstrate that even small-scale sampling can yield significant discoveries and expand the known distribution of rare bats in the Congolian rainforest. This underscores the urgent need to prioritise biodiversity studies in the region to fully assess its richness and implement effective conservation measures.