Superficially extremely similar to the Grayling, H.
semele. This species replaces semele in the extreme south of
Europe in Greece, Sicily (partial range overlap), Sardinia, Corsica and
north Africa. The male genitalia are different. The best way to separate
these species is to recognise in which range the butterfly was found! In
Greece there is another species that it very closely resembles -
Delattin's Grayling, H. volgensis.
In Greece this butterfly is
of the subspecies senthes, although I believe some people treat
this as a full species in its own right. The fact that the entire
Hipparchia group appears to be subject to much debate and appears to
be in state of speciation throughout its range, I leave it to the
members of my audience to make their own choices!