Type species: medardaria Herrich-Schäffer
Synonyms: Dichroptera Herrich-Schäffer (type species medardaria);
Bargosa Walker (type species chandubija Walker = medardaria).
This genus consists of delicate pinkish brown species; the wings above
are irrorated and striated with darker brown and marked with dark brown or
black, variably at the discs and apices of the wings and in medial fasciae. The
underside is pinkish buff with a blackish border; the discal spots and fasciae
are usually strongly picked out in black.
The male genitalia are elongate, slender, as is the eighth abdominal
segment. The uncus is strongly curved, the socii very small. The valves are
simple, long and narrow, unadorned, apart from deep coremata at the sacculus,
bearing hair pencils. The aedeagus vesica is a simple or weakly diverticulate
tube with a short, blunt cornutus on the weak diverticulum that may have a zone
of corrugation associated with it. The juxta is discussed below.
The female genitalia have the bursa elongate with no marked
sclerotisation at its base or in the ductus apart from a longitudinal band that
is stronger in P. delostigma Prout and P. paroobathra Prout. The
signum is a circular scobinate sclerotisation that forms a slight indentation on
the surface of the bursa. The ostium opens posteriorly to a narrow, transverse
ribbon of sclerotisation that represents the eighth sternite. There is a
conspicuous, balloon-like extension dorsally to the intersegmental membrane just
anterior to the ovipositor lobes; this membrane also bears a ring of scales that
is usually lost when clearing the genitalia. The ballooning of the membrane is
also seen in the next genus.
The medardaria group of Petelia (eastern Oriental taxa not
investigated) can be divided into three groups. The juxta is long, narrow, with
lateral thickenings: in one group these converge to fuse distally and in the
other they remain separate. In the first group the hindwing underside discal
spot is weak or absent, and component species are immaculata Hampson (Sri
Lanka, India), delostigma Prout, paroobathra Prout (both described
below) and undescribed species from Seram (slide 12914) and N.E. India (slide
12909). The second group probably exhibits the plesiomorphic state of the juxta
but can be subdivided on the basis of two probable apomorphies. A group of four
shares the feature of a doubly humped uncus: medardaria, an undescribed
species that ranges from New Guinea to Vanuatu (slide 9531), aesyla Prout
(Fiji) and trifascia Holloway (New Caledonia). A group of three species
has the cornutus basal in the aedeagus vesica with a zone of corrugation distal
to it: distracta Walker and tuhana Holloway, both described below,
and an undescribed species from New Guinea and the Bismarcks (slide 12926).
The genus Polycrasta Warren (two species, Moluccas to Solomons)
is probably closely related to Petelia. The species are larger, with
marked sexual dimorphism. The male genitalia show some similarity, but the
aedeagus vesica is more complex. The female genitalia lack a signum.
All host records for Petelia are from Rhamnaceae (Sato, 1976, and
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