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Myotis ciliolabrum

Western Small-footed Myotis

Order: Chiroptera
Family: Vespertilionidae

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

The western small-footed myotis occurs in limited areas of southwestern Canada, throughout much of the western United States, and into Mexico. It is better adapted to moist areas than to dry ones. It roosts alone or in small groups in rock crevices, mines, caves, or buildings, and even occasionally uses in an abandoned swallow's nest as a roosting site. It eats insects, including flies, beetles, moths, and ants. Like many bats, the western small-footed myotis mates in the fall and sperm is stored in the female's body over the winter, while she hibernates. In the spring, the female ovulates and fertilization occurs. A single pup is born in May, June, or July, and is ready to fly when it is about a month old.

Also known as:
Small-footed Myotis, Western Small-footed Bat

Sexual Dimorphism:
Females are larger than males.

Range: 76-90 mm

Range: 2.8-7.1 g


Merriam C. H. 1886. Description of a new species of bat from the western United States (Vespertilio ciliolabrum sp. nov.). Proceedings of the Biological Society of Washington, 4:14.


Mammal Species of the World

Distribution of Myotis ciliolabrum

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