|
Platyja Hübner
Type
species: umminia Cramer, Java.
Synonyms:
Cotuza
Walker
(type species drepanoides Walker, India, Hong Kong, W. Malaysia); Cremnodes
Felder
(type species lemur Felder, Moluccas) praeocc.;
Ginaea
Walker
(type species removens Walker, India = umminia);
Iontha
Doubleday
(type species umbrina Doubleday) syn. n.; Mocrendes
Nye
(replacement name for Cremnodes); Yerongponga Lucas
(type species exequialis Lucas, Queensland).
This
genus can be defined by two highly distinctive features: tripectinate antennae
in males and an unusually strongly looped postmedial on the forewing. The extent
of the genus is still being explored (Zilli, Yen & Holloway, in
prep),
but it will probably also embrace all or part of Facidina Hampson
(see below).
The male
antennae are ventrally serrate, the serrations sometimes long, and always deeper
than the lateral rami that, when they occur, render the antennae tripectinate.
The lateral rami are short in some species (e.g. sumatrana
Felder)
and vestigial in others (e.g. ciacula Swinhoe and umbrina
Doubleday).
The legs in males usually bear conspicuous scale tufts and scent pencils, and
the abdomen of most members of the Iontha group
has a conspicuous black brush of scales at its apex. The forewing postmedial
runs from the costa well distal to the reniform and is often angled immediately
distal to it. It then extends to beyond CuA2 and then loops back towards the
reniform to run basad along CuA in the cell before flexing back to meet the
dorsum at approximately its centre. The area enclosed by the loop in the spaces
each side of CuA2 may be distinctly paler and divided by dark along the vein.
Sexual dimorphism is weak to (in the Iontha group)
extreme. The genus can probably be subdivided into a series of species groups,
some of which conform to older generic concepts such as Iontha
and
Cremnodes
that
could be given subgeneric status. It is found throughout the Indo-Australian
tropics, and inclusion of Facidia Walker and Megacephalomana Strand
would extend it to Africa. The latter genus includes species from Sri Lanka (divisa
Walker)
and Ambon (pilosum
Pagenstecher)
according to Poole (1989).
The
species Facidina suffumata Guenée has the same forewing facies type
as Platyja,
and the male antennae are tripectinate. The species was described from Java
(East India Company specimen; other material from this source includes a pupa
within a tightly rolled leaf) and is known from Thailand as a fruit piercer (Bänziger,
1982; Kuroko & Lewvanich, 1993). The type species of Facidina
Hampson
is polystigma
Lower
(Australia, S. Moluccas to Solomons), and the genus also includes the African semifimbria Walker.
The three species were brought together formally by Poole (1989), reflecting an
unpublished arrangement in BMNH. However, polystigma
lacks
the characteristic loop of the forewing postmedial of Platyja,
it being punctate, white and only slightly sinuous. The male antennae are
fasciculate, and the genitalia have valves with complex, bilaterally asymmetric
distal processes, a complex, elongate, bilaterally asymmetric juxta, and a long,
slender, sinuous aedeagus. The New Guinea species argenteopunctata Bethune-Baker, placed in Platyja
by
Poole (1989), shares all these features, and is therefore transferred to Facidina, comb. n.;
suffumata
Guenée
is transferred to Platyja, comb. n.,
as is semifimbria
Walker, comb.
n.,
as it also has characters typical of Platyja.
The male
abdomen has the eighth segment variably modified, but the sternite is usually
bilobed on the anterior and posterior margins, sometimes very weakly, but
strongly so in some members of the Iontha group.
The genitalia have a robust uncus associated with a scaphium. The valves are
simple, narrow, somewhat as in Ischyja but
with more variety, tending only to have processes (or a slight bifurcation) at
the apex in the Iontha group; an exception in the Bornean fauna is ciacula
where
there is a prominent digitate process from the valve costa at one third. The
juxta is similar to that of Ischyja but with the narrow, central, more weakly sclerotised
zone extending dorsally, with a slight splaying at its distal end. The aedeagus
vesica has a number of slender diverticula with diverse ornamentation including
strong cornuti in some taxa.
The
female genitalia have the ostium associated with the posterior part of the
seventh segment, where it is concealed by a bilobed extension of the posterior
margin of the sternite.
The
adults of several species have been noted to pierce fruit; the records of the
type species from Annona (Annonaceae) in Robinson et
al. (2001)
may be of this nature rather than of larval hosts.
<<Back
>>Forward <<Return
to Content Page
|
