The Little Brown Myotis is small with moderately long ears and pointed tragus. The fur is long, silky and brownish in color. Length of head and body is 4-5 cm. Weight is 8 g.

The Little Brown Myotis is nocturnal and generally eats insects in flight. The habitat of this bat is temperate forests and woodlands.

It roosts in colonies of up to several thousand in warm locations. Breeding occurs in late summer but fertilization is delayed until spring. The colonies migrate 290 miles and hibernate off and on through the winter. In spring females form large maternity colonies. Gestation is 50-60 days with a single offspring born in summer. Young are independent at 1 month.

The Little Brown Myotis is found in Alaska (USA) to Labrador and Newfoundland (Canada), south to S California, N Arizona, and N New Mexico (USA).