Savi's Pipistrelle

Savi's pipistrelle is a small dark-faced bat measuring about 40–54mm and weighing 5–10g. Its ears are short, broad, and rounded, with a short rounded tragus; the face, ears, and membranes are blackish. Long dense dorsal fur is brown, sometimes silver- or gold-tipped, and contrasts with a dirty-white to pale-yellow belly. The slender tail tip projects several millimetres beyond the membrane. (Wikipedia, general species account)

The species has a wide Palearctic distribution from the Mediterranean and North Africa through Central Asia toward East Asia. It is associated with rocky country and often roosts in cliff cracks, buildings, and other crevices. Like other pipistrelle-sized bats it catches flying insects on the wing, frequently foraging over open ground and around rock faces. The opened source did not provide a Mongolia-specific locality or population account. (Wikipedia, general species account)