Phylogenetic analyses of nuclear (Mcm7, nrITS, nrLSU) and mitochondrial (mrSSU) DNA sequences revealed geographically disjunct lineages in Leptogium hibernicum. One of these lineages is described here as Leptogium krogiae, which differs from L. hibernicum in the thinner thallus (190–210 µm vs. 390–480 µm), shallowly striate lobes instead of deeply furrowed lobes, isidia that are seldom distinctly flattened, and apothecia with a subhymenial euparaplectenchymatous layer. Leptogium krogiae is a widespread epiphyte in mist-affected woodlands and montane forests in East Africa and appears to be a common species.