any of several small to medium-sized common bats of the genera Myotis and Eptesicus, found worldwide in caves, trees, and buildings, including M. lucifugus(little brown bat) and E. fuscus(big brown bat) a widespread North American species.
any of the bats belonging to the genus Myotis (little brown bats) or Eptesicus (big brown bats). Both are vesper bats, and both are widely distributed, being found in almost all parts of the world. Both genera are insectivorous
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