Just right of its right ear, you can see the tip of the tail which is nearly as long as its entire body.
To be honest: this bat could possibly also be the Lesser Mouse-tailed Bat (Rhinopoma hardwickei), which is slightly smaller (body lenght of 5.5 cm).
Based on the animal's size, I have identified it as the Greater Mouse-tailed Bat (Rhinopoma microphyllum).
I found this wonderful creature in one of the caves near the National Museum of Mali in Bamako.

Bamako area, Mali, 26 February 2010