These are common bats and fairly easy to see roosting over or beside water during the day. A distinctive feature is the way that they roost in groups of anything from 3 to 45 in a line one above the other about 2 to 4 cms apart.

They roost on the lower side of a large branch, the steep face of a bank, below a bridge or, as in this photo, on the lower side of a leaning tree trunk.

It is found from Mexico to South America east of the Andes as far as Mato Grosso and Minas Gerais, Brazil

There are illustrations in Eisenberg & Redford, Plate 4; and in Emmons, Plate 5.