Eptesicus Fuscus is a species of bat commonly known as the Big Brown Bat. There are several synonymic names for this species including Vespadelus fuscus, Nyctalops fuscus, and Euderma fuscum. These synonyms are based on a variety of morphological, genetic and geographic differences that distinguish them from other members of the Eptesicus genus. The Big Brown Bat is found throughout most of North America and typically inhabits urban and suburban areas where it feeds on insects, primarily at night. Despite being an important insect predator, the Big Brown Bat can often be viewed as a nuisance by humans due to its tendency to roost in attics and other structures.