Natural history and conservation.—Most of the information
available on the ecology, reproduction, and natural history of
M. midastactus comes from museum labels and from L.
Aguirre’s fieldwork in Bolivia. This information is synthesized
under accounts for M. simus in Espinoza (2007) and Moratelli
(2012). Myotis midastactus has day roosts in holes in the
ground, under thatched roofs, and hollow trees (Espinoza 2007;
Moratelli 2012). In the first 2 roosts, it was found together with
the Argentine brown bat, Eptesicus furinalis d’Orbigny and
Gervais, 1847 (Espinoza 2007).