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Fascellina Walker

Type species: chromataria Walker, Sri Lanka.

This genus can best be defined in its totality by characters of wing facies. Most taxa have an excavation at the tornal margin of the forewing, but this is shared with Corymica Walker, a potential sister-genus. On the forewing there is usually a prominent submarginal fascia that is strongly angled subcostally; other fasciae are usually obscure. This is reflected on the hindwing by a straight, often doubled medial fascia or, in more apomorphic taxa, a more irregular postmedial (weaker and evenly curved in plesiomorphic ones). On the underside the ground colour is usually chrome or orange-yellow, irrorated and marked with rich brown. Most taxa have the forewing postmedial and submarginal enclosing a band of brown colour that expands to the subcostal angle of the submarginal, then narrows to the costa. The fasciation of the hindwing underside reflects that of the upperside, tending to be irregular and weakly defined in more apomorphic taxa. The male antennae are filiform, but densely ciliated.

The male genitalia are, for more plesiomorphic taxa, typical of the hypochrosine ground-plan, with an asymmetric furca, left side longer. The eighth sternite tapers distally, becoming narrower and more triangular in apomorphic taxa. For Bornean taxa, all except subsignata Warren, punctata Warren and clausaria Walker have the tegumen swollen laterally, somewhat balloon-like, membranous. In all of this group except meligerys Prout there are prominent setal bases on these balloon-like expansions and in all except altiplagiata Holloway the basal coremata of the valves are much more densely (the setal bases) and darkly setose. In this group there is the plagiata Walker/altiplagiata sister-pair, pulchracoda sp. n. sister to the Himalayan dacoda Swinhoe, and a large group where the most prominent hindwing fascia on the upperside is irregular and those on the underside faint and also irregular. All of this last group except meligerys have the uncus bifid and the setae or scales on the tegumen membrane short, spindle-shaped rather than filiform or straplike, and this membrane extends dorsally on either side of the uncus. The type species belongs to this last group as do the Bornean species aurifera Warren, albicordis Prout, castanea Moore and quadrata sp. n. All New Guinea species (a complex of two or three, e.g. papuensis Warren, glaucifulgurea Prout) and two out of three Sulawesi taxa (cydra Prout, possible sister-species to aurifera, but with wing shape as in meligerys, and cervinaria Snellen (?= celata Walker = olivataria Walker)) also belong to this terminal group. The third Sulawesi taxon (slide 12806) falls within the swollen tegumen group but lacks the apomorphies of the terminal group.

The female genitalia lack a signum in clausaria and have an extensive, partially scobinate lamella vaginalis. This latter is less extensive in aurifera, but there are broad, sclerotised pockets laterally on the seventh tergite; a signum is present in the form of a pinched up, short, serrate ridge. In both species the ductus is unsclerotised except at the extreme base and broadens out gradually to the bursa.

The life history of the type species in India has been described by Singh (1953) and Bell (MS). Bell referred to the larva as rather spindle-shaped, cylindrical, strongly looped when resting (usually on the edge of a leaf). The skin is dull, smooth, with sublateral conical processes on A2, A3 and A4, and a prominent fleshy reddish cone on A8. It is coloured a dull brown-pink, suffused with rich dark brown dorsolaterally and laterally that is marked with oblique light brown lines or suffused light brown. There is a dark brown triangular mark dorsally, anteriorly on A5, crossed by a light brown line. The conical processes of A2 are bright orange. A similar larva is illustrated in Sugi (1987) and attributed to chromataria but the taxonomy of the complex in mainland Asia requires revision. The conical processes appear to be characteristic of the genus.

Pupation takes place in a light brown silken cell between two leaves joined firmly.

The resting postures of larva and adult in Fascellina are similar to those observed in Corymica.

The host-plants recorded are all Lauraceae: Alseodaphne, Cinnamomum, Litsea, Machilus, Phoebe. Sugi (1987) noted Lindera, Machilus and Illicium as hosts for chromataria in Japan, all Lauraceae, or the distantly related family Illiciaceae (Illicium). Corymica Walker, possible sister-genus, is also known only from Lauraceae.

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