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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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