In the subgenus Peronymus of Peropteryx the wings are white from the forearm outward. In the proboscis bat, Rhynchonycteris, the upper surface of the forearm is dotted with tufts of hair. The face and lips are smooth. A nose leaf is not present. The ears are often united across the top of the head, and a tragus is present.
Many forms have glandular wing sacs that open on the upper surface of the wing.
These glands secrete a red substance of strong odor. In the genus Taphozous a glandular mass is located between the lower jaws. In the members of this family the tail pierces the tail membrane, and its tip appears completely free on the upper surface of the membrane, the base of the tail being loosely enclosed in the membrane. Thus, in flight the tail membrane can be lengthened by stretching the hind limbs, the membrane then slipping quite easily over the tail vertebrae. Most forms can steer and turn exceptionally well.