A mouse-eared bat reported from the Caribbean region and northern South America. The classification that groups island and mainland specimens has been debated.
In mainland specimens, dorsal hairs are dark at the base and tawny-olive at the tips, while the underside is pale. The Curaçao specimen was described as smaller and paler than M. nigricans.
The 2013 review examined 12 mainland specimens and only one specimen from Curaçao. These records rest on limited sampling, and the review does not describe diet or roosting.
An extinction-risk assessment has not been added yet.