SIZE Head and body length 10 to 13cm. Forearm length 10.2 to 11.2cm.
Females are smaller than males.
During the breeding season females congregate in maternal colonies, while males congregate into all male colonies. Groups in excess of 100 bats are unusual. The contraction in range occurred well before European settlement. Very sensitive to disturbance, human intruders to a cave colony may cause the group to become nervous and leave. Many roost caves have been destroyed or are threatened by mining activity.