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Throanagonia
Gen. n.
Type species:
albiocellata
Wileman & West comb. n., Philippines (Palawan, Luzon).
This genus has the facies characteristics of members of the Throana Walker complex of genera discussed by Holloway (2006: 303-310): angled margins to the wings that are additionally moderately crenulate; prominence on both surfaces of a white orbicular spot on the forewings (the reniform is transversely bipunctate in darker grey). There are also internal features that suggest membership of this complex, as noted below. The labial palps are long (3 or 4 times the length of the head), directed forwards, with the slender third segment shorter than the second and angled upwards.
The wings are an ashy grey with finely crenulate, dark, submarginal and postmedial fasciae; there is a darker zone between the latter and a weak medial, and the forewing has an irregularly crenulate antemedial just basal to the orbicular. The forewing costa is gently sinuous, bowed over the basal half, with a slight concavity.
The male abdomen lacks conspicuous phragma lobes between the first and second tergite and has an unmodified eighth segment. In the genitalia, the uncus is short, hooked, and the tegumen is relatively long, both conditions relatively extreme compared to other Throana group taxa. The valves are much more complex, divided into three or more processes, some slender, some with elongate setae; the ensemble can show bilateral asymmetry. The aedeagus vesica is elongate, tubular, set at an angle from the aedeagus when everted.
The female genitalia have a large, complex sterigma between a short eighth segment and a deep seventh one, with some invasion of the sternite of the latter. There is a characteristic lamella postvaginalis with a crown-like margin. The corpus bursae is generally rugose to scobinate.
There is a further species in Sulawesi that may be congeneric. It has generally similar facies, though more reddish brown in tint, and forewing shape, except the postmedial fascia on all wings is more linear, fine, pale with a dark edge basad, sinuous on the forewing (most sharply curved in the discal area) and shallowly zigzag on the hindwing. The genitalia are somewhat different from those of the Philippine and Bornean species. The male (slide 20107) has a stiletto-like valve, broadening slightly over the basal third and having a slender, delicate, digitate process interiorly that is about one third the length of the valve. The uncus is as in other species as are the aedeagus and vesica, except the latter has a long, slender cornutus at its apex. In the female genitalia (slide 20108), the ostium is set in a notch at the posterior apex of the triangular seventh sternite, and is flanked by a pair of asymmetrically bifid spines. The ductus is sclerotised to just anterior to the seventh sternite, then is more membranous, slightly corrugated, expanding gently and ultimately asymmetrically into a spherical corpus bursae that contains a long band of scobination and a crinkled, sclerotised pleat that runs back into the expanding portion of the ductus. It is probably sister-taxon to the type species and the two Bornean ones described below.
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