Myotis nigricans
Adult bats of the species have a body length of 4 cm, a 3cm forearm and weigh approximately 4 g. The dorsal colouration is brown, varying geographically from light to dark, with a ventral colour similar to the back. They form groups ranging in size from less than 10 individuals to more than 300 and are found in caves, the hollows and bark of trees, cracks in rocks and thick foliage. They are widely found in anthropized areas, sheltering in the roofs of buildings, shutter boxes and air-conditioning ducts.
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