In this study we report findings in roosting ecology, ectoparasites, echolocation characteristics and the phylogenetic position of Cardioderma cor, an impressive bat species that is distributed throughout the savannas and woodlands of eastern Africa. For individuals caught in Mago National Park, Ethiopia, we recorded broadband frequency-modulated ultrasound signals having very short duration (2 ms) with three harmonic components. The mean peak frequency of the first harmonic was 50.4 kHz and the mean inter-signal interval was 186 ms. Phylogenetic reconstructions of all known species from the family Megadermatidae based on DNA sequences of two mitochondrial and four nuclear genes yielded incongruent topologies (both Bayesian inference and maximum likelihood analysis) with only weak support for nodes. The phylogeny that combined all six loci into a species tree was not congruent with any previous inference based on dental or cranial characteristics, but it suggested separate generic status of two Megaderma species. However, additional genetic data are necessary to resolve the phylogeny of Megadermatidae, a group that probably evolved by simultaneous divergence of all five extant lineages.