A new species of Rain Frog (Brevicipitidae, ) endemic to Angola.

Recent molecular phylogenetic work has found that Merrem, 1820 comprises two major clades, one of which, the group, is widely distributed across southern sub-Saharan Africa. This group is notable for harboring abundant cryptic diversity. Of the four most recently described species, three are members of this group, and at least five additional lineages await formal description. Although has long been known to occur in Angola, no contemporary material has been collected until recently. The three most widespread taxa, , , and , may all occur in Angola, but accurate species assignment remains challenging given the rampant morphological similarity between these taxa, and, until recently, the lack of genetic resources. Phylogenetic, morphological, and acoustic analyses of recently collected samples from disparate localities within Angola provide evidence for an undescribed species that is sister to . The new species can be diagnosed from its sister taxon by lacking pale spots along the flanks, a pale patch above the vent, and a short, dark band below the nares (all present in ). Additionally, the male advertisement call differs from the three other that might occur in Angola in having both a longer interval between consecutive calls and a higher average dominant frequency. We here describe this lineage as a distinct species, currently only known from Angola, and discuss the presence of other taxa within Angola.