Blepharomastix cayugalis is a moth in the Crambidae family. It was described by Schaus in 1924. It is found in Guatemala. The wingspan is about 14 mm. The wings are chamoisee colour with fuscous markings, the lines consisting of fine diffused scales. The basal half of the costa of the forewings has dark irrorations. The hindwings have a sinuous medial line, a wavy postmedial line to the termen at the submedian fold and a terminal line.