Type species: asigna van Eecke.
The unique species in this genus has usually been placed in Thosea as,
apart from its pale golden brown colour, the external appearance is very similar
to species of that genus. However, it differs in features of both genitalia and
larvae indicating that it is best excluded from Thosea, lacking the
traits presumed to be apomorphic and used in the definition of that genus.
In the male genitalia the uncus has a ventral subapical spur, possibly
plesiomorphous within the 'crescent signum' group. The furca arms are not
flexed back into the abdomen and are more robust, and sinuous than in Thosea;
they are conspicuously setose. The aedeagus terminates in a spine and the
anellus is also coarsely scobinate in the zone near the attachment to the
The ductus bursae of the female is short, unspiralled except for one
twist where it enters the bursa. The base of the ductus and the lamella
postvaginalis are distinctively sclerotised, shaped and scobinate, the latter
overlapping the ostium in a semicircular flap.
The larva, illustrated by Wood (1968) and in below, is not lozenge
shaped but more elongate, deep sided as in members of the bisignate group. The
lateral row of processes is complete, uniform, but the dorsolateral row has
strong tubercles on T2, T3, Al, A5 and A8 or A9 (indeterminate from the
illustration) and the rest vestigial or absent. This situation (or variation on
the theme) is also seen in other genera of the 'crescent signum' group such as
Setora but the pattern along the dorsum, described in the specific
account, is distinctive.
asigna in Peninsular Malaysia (P.A.C. Ooi)
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