Abstract The Sakeji horseshoe bat Rhinolophus sakejiensis is an endemic to south-central Africa. Until recently, it remained known only from the type series of three specimens collected in Nchila Wildlife Reserve, north-western Zambia. The phylogenetic position of R. sakejiensis was evaluated based on morphologic traits and it was suggested that it represents a part of the ‘clivosus-complex’ within the Rhinolophus ferrumequinum clade of the genus. In this study, we provide an insight into the phylogenetic position of R. sakejiensis employing molecular data, using a newly discovered specimen that originates from the identical area as the type series. We assessed the genetic relationships of R. sakejiensis using the mitochondrial cytochrome b gene. This analysis revealed this species to be phylogenetically distinct from morphologically similar congeners of the capensis, fumigatus, and ferrumequinum species groups. In fact, it does not belong to any recognised species group but rather represents a distinct evolutionary lineage – along with another African relic bat, Rhinolophus horaceki. The divergence time of R. sakejiensis from R. horaceki, its closest relative, was estimated to have occurred in the Middle Miocene, roughly at 15.3 Ma, a period of dynamic environmental changes that may have led to widely separated occurrences of various relic bat lineages.
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