The hairy-legged myotis is a small bat, measuring just in total length, and weighing about . The body is covered with long, sometimes woolly, fur, which varies from greyish to reddish brown in colour. The common name refers to the presence of thick fur on the legs and on the upper surface of the
uropatagium, the flight membrane stretching between the legs. Although other, related bats, also have fur on this membrane, it is more extensive in this species, reaching at least halfway between the knee and the foot. There is also fur on the upper surface of the
plagiopatagium, the main part of the wing between the arms and legs. This fur can be quite thick, and covers the part of the wing closest to the body, reaching as far as the elbows. The hairless portions of the wings are dark brown to black in colour. ==Biology and behaviour==