Eliot state of C. bromus, the female always have a spot in FW space 1b on the upperside. The underside have a similar corresponding spot. http://yutaka.it-n.jp/hes/93320001.html
PS. Baoris have blackish antennae. Male with a dark brand in a pale area UnF; female always with a space 1b spot on both surfaces. http://yutaka.it-n.jp/hes/93210001.html