The holotype for the species was collected in Chiriquí Province in Panama; it was sent to Miller by British zoologist Oldfield Thomas.

Thomas had received the specimen from HJ Watson, who was the owner of extensive plantations in Panama.

[5] Its taxonomy has been revised several times, however, with some authors considering it a subspecies of the dwarf bonneted bat.

[6] E. nanus was consistently maintained as a subspecies of the dwarf bonneted bat from 1932 until 2007, when Eger et al. recommended that it should be elevated to a species once more.

Miller stated that the species reminded him of a miniature Wagner's bonneted bat.

It meets the criteria for this designation because it has a large range, it occurs in several protected areas, and its population is unlikely to be declining at a rapid rate.