Erebia ajanensis is a butterfly found in the East Palearctic (China, Korea, Amur, Ussuri, Magadan) that belongs to the browns family.
ajanensis Men. (= eumonia Men.) (37 g), from the Amur and Ussuri, differs but little from the nymotypical form [of ligea]. The white band on the hindwing beneath is broader and more continuous, there being some obsolescent white spots near the base, which are occasionally also found in the nymotypical