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Nyctinomops femorosaccus

Pocketed Free-tailed Bat

Order: Chiroptera
Family: Molossidae

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Credit: New Mexico Bat Call Library, W. L. Gannon
Image of Nyctinomops femorosaccus
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Conservation Status: Least Concern.

A small fold, or "pocket" in the wing membrane of the free-tailed bat, near its knee, gives this bat its common name. Pocketed free-tailed bats have large ears and long wings, and fly rapidly, generally pursuing insects on the wing. They eat many kinds of insects, but seem to prefer small moths. Small colonies, usually fewer than 100 bats, roost together in caves, crevices in rocky cliffs, or buildings. Females have a single pup each year, not twins.

Sexual Dimorphism:

Average: 109 mm
Range: 99-118 mm

Range: 13.8-17 g


Merriam, C.H., 1889.  Descriptions of fourteen new species and one new genus of North American mammals, p. 23.  North American Fauna, 2:v + 1-48, 6pls.


Mammal Species of the World

Mammalian Species, American Society of Mammalogists' species account

Distribution of Nyctinomops femorosaccus

Image of Nyctinomops femorosaccus
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