Similar species: 
Syngamia latimarginalis (Walker, 1859)
Based on images, Syngamia latimarginalis can be separated from Orphanostigma abruptalis as in the latter species, the FW postmedial line is more deeply excurved between vein 5 and 2. Both wings with two black marginal lines and grey cilia. Many individuals of Syngamia latimarginalis have pale area on the inside of the disco-cellular module and sometimes on the inside of the postmedial near the costa. This pale area is mostly absent in Orphanostigma abruptalis. The basal area as well as the medial area and the postmedial area has a single colour (typically two-toned in Syngamia latimarginalis). The characters mentioned for separating the two species in Hampson, 1896, Vol. 4: the black band on forelegs and the black line on the abdomen does not seem to be valid for separating the two species.