Diagnosis. This and the next three species are characterised by an ochreous cream zone along the forewing costa to the postmedial and a rather oblique reniform mark of the same colour. The ground is virtually black but suffused pale mauve from the postmedial to the distal margin (also to a lesser extent on the hindwing). The course of the postmedial is zig-zag, oblique, with a distinct indentation of the mauve area centrally. The postmedial in rostrilinea is more basal than in the other species, rendering the mauve margin broader. The male labial palps in all the species are a similar colour to the ochreous zone of the forewing and recurved to the centre of the thorax.
Taxonomic note. The holotype is a female, with a much darker forewing than the male illustrated here. The four species of the group are currently only known from Borneo and fall into pairs, one species of each from heath forest and one from montane forest, though samples are very small.
Geographical range. Borneo.
Habitat preference. The holotype is from G. Penrissen in Sarawak. Three specimens have since been taken at 1790m in upper montane forest on G. Mulu and one at 1500m in montane scrub on the limestone G. Api.