ABSTRACT
The vampire bats were rather late in being recognized in the taxonomic literature; the first species was not described until 1810 and the first genus was not recognized until 1823. Of the three generally recognized species of vampire bats, rotundus and ecaudatus were recognized relatively early, both being generically distinguished, as Desmodus and Diphylla respectively, by 1824. There are important distributional differences in details among the three species. In modern terms, this difference is basically whether to emphasize the clear phylogenetic derivation of vampires from phyllostomids, particularly from some group of fruit or nectar feeders, or conversely, to emphasize the truely unique modifications of the vampires. Phylogenetic character analysis is difficult with vampire bats because of the close relationship among all three species and the very considerable morphological gap that separates them from any other phyllostomids.
