Amesia Duncan

Type species: sanguiflua Drury, India.

This and Eucorma Jordan are components of a subclade of Clade 12 of Yen et al. (2005) but, whilst Amesia is recovered as monophyletic, Eucorma Jordan is paraphyletic in at least some of the analyses, forming the basal branches of a clade that also includes the genera Erasmia Hope (monobasic, N.E. Himalaya) and, paired, Erasmiphlebohecta Strand (monobasic, Taiwan) and Chalcophacdra Jordan (two species, N.E. Himalaya, Vietnam). Amesia is placed as sister to this clade or embedded within it in the analyses. Eucorma is most frequently associated with Erasmia; Erasmia is the older name.

Yen et al. (2005: 275) stated that the whole clade shared a specialised copulatory mechanism where the male genitalia are muscle-bound, immovable, reduced, membranous and enclosed by the highly modified eighth segment, of which the two sclerites are also not articulated. The inner margin of the valve sacculus has a large internally directed spine, though such a feature also occurs elsewhere, e.g. in Eterusla Hope. The aedeagus is also very long, with a curved bulbus ejaculatorius. The female genitalia appear unspecialised.

The Amesia subclade is defined by further modifications of the male abdomen and by some shared but cryptic wing facies characters within the clade. Amesia has the male basal abdominal scent organ reduced to a depression, and a hair-pencil. The female genitalia have the ostium located within a deep excavation of the posterior margin of the seventh sternite. However, these features are also seen in some other clades, e.g. in Opisoplatia Jordan.

The moths are large, relatively robust with wing patterns that are probably mimetic, resembling various Euploea butterflies. The ground colour is black but the veins may be lined slightly paler. There are fields of white spots in the postmedial zone of all wings, though those of the hindwing may be pale blue amid a rich, deep blue iridescence over the distal part. The wings may have the veins edged paler over a short distance submarginally (more extensive in the only Bornean species, which also has blue spots medially on the hindwings). Some species have yellow patches and bars in the basal part of the forewings. The antennae of both sexes are filiform.

The male abdomen has the eighth segment strongly modified, with ‘manta ray’ processes from the tergite and extreme complexity in the much smaller sternite, as illustrated by Yen et al. (2005: fig 28). The genitalia have the uncus vestigial, but with complex structures in the anellar region (Yen et al., 2005: fig 34). The valves are setose, rather deep, tongue-like or bilobed.

Amesia contains four species: aliris Doubleday and sangiflua in mainland Asia, the latter extending to Sumatra and Java; namouna Doubleday; apoensis Kishida & Horie from Mindanao in the Philippines.

Tarmann (1992b) recorded the larva of the type species as feeding on Helicia (Proteaceae).