The whiskered bat is the smallest member of the Myotis genus in Europe. It is very similar in appearance to Brandt's bat (Myotis brandtii); indeed Brandt's bat was only separated from the whiskered bat as recently as 1970. Both species have shaggy fur, but generally speaking, the whiskered bat is darker in colour; the back is nut-brown, grey-brown or light brown, the belly is usually dark or light grey, and the wing membrane, nose and ears are blackish-brown. Definite distinguishing features between whiskered and Brandt's bats are the shape of the tragus, the teeth and the penis, which in Brandt's bat has a club-shaped tip.