They are found in western North America. Their range stretches from southern British Columbia to Mexico, but they are most common in the American southwest.
They are found mostly in dry, rugged habitats, though there is usually a water source nearby. They roost in the high cliffs of canyons.
They reach up to 4.5 inches long but can be smaller. The wings are pinkish and have a wingspan of up to 14 inches. Their fur is black on top with white spots on the shoulders and one on the rump. The fur is white underneath. They have large, pinkish ears with distinct tragus inside the ear and small, sharp teeth. They have tiny, clawed feet for grasping as they roost. The flap of skin between their legs and tail called the uropatagium.
They are unusual in that they roost alone (not in colonies) and can be somewhat territorial. They go into torpor during the cold months, though some will migrate to warmer climates in winter. They use echolocation to find moths in the dark. Their echolocation is a low enough frequency that it can be heard by humans.
They eat moths (insectivorous), catching them in flight, at night, using echolocation.
They can be preyed upon by owls and other predators in their habitat.
Females have one offspring in June which she will nurse until it is old enough to hunt moths.
They are one of the rarest bats in North America.