Diagnosis. The long, narrow forewings are distinctive, with characteristic markings in the apical part: a white discal spot associated with a greyer zone towards the costa and distally, the distal part of this grey area being strongly terminated by a pale, concave border that encloses a dark brown band that curves towards the wing apex. The male antennae have a slight swelling at one third.
Taxonomic note. The wing shape and distal markings are similar to those of the Indian “M.” [Herminia]velifera Swinhoe, listed in Mecistoptera by Poole (1989), but excluded, along with several others listed in Poole by Lödl (1997) when revising the genus. “M” albisigna Hampson (India), also listed by Poole and having similar facies to emmiae, but darker and greyer, is another of these. Only females are known of velifera, but the only specimen of albisigna, the holotype, is male. Whilst the genitalia are not dissimilar to those of emmiae, they do not share any features that are obvious apomorphies, nor do they have the definitive features of Mecistoptera. The female genitalia of emmiae are very different from those of velifera where there is a spiny ostial pouch that leads through a constriction to a centrally swollen ductus that is also distally constricted at the junction with an irregular membranous corpus bursae without a signum. In emmiae the ostium is membranous, tapering gently into a sclerotised basal section (almost a colliculum) of the ductus bursae to just short of the origin of the ductus seminalis. Beyond this is a shorter, thick-walled, corrugated but unsclerotised section that joins the elongately ovate corpus bursae asymmetrically, subbasally. The corpus bursae is scobinate and corrugated throughout, mostly longitudinally but with a focus on a slightly more sclerotised strip that runs for almost the whole length from the point where the ductus joins. This group of species may extend much further east, as Robinson (1975: 234) tentatively associated a Fijian species with albisigna, and Edwards in Nielsen et al. (1996) recorded what is probably this Fijian species in Australia. Further material is needed to establish the affinities of these species. However, the phragma lobes between the basal two tergites are large as in the rest of the genus-group.
Habitat preference. Bornean material is limited to three specimens from Bidi in the lowlands of Sarawak.
Biology. Gardner (1947) described the larva of velifera as having the prolegs of A3 very small and those of A4 reduced, as is the case in typical Mecistoptera. The primary setae are short, and the head is rather strongly transverse. The colour is blackish with yellowish speckling and marking, and there are orange spots posterior to the spiracles.
The host plant recorded was Aspidopterys (Malpighiaceae).
