(Ploneta) diducta Snellen comb. n.
Ploneta diducta Snellen, Piepers & Snellen, 1900: 105.
Ploneta diducta Snellen; Hering, 1931: 689.
Diagnosis. The male has rather elongate dark brown forewings, distinctive features
of which are an oblique, fine, pale submarginal and a notch in the margin at the
position of vein R5, rendering the wing falcate. The female is larger
with rounded margins to the dark speckled forewings; there is a trace of a dark
Geographical range. Sundaland, S. Thailand.
Habitat preference. The species was recorded for Borneo by Hering (1931),
but no recent material has been seen.
Biology. The larva was described and illustrated by Piepers & Snellen (1900)
and by Kalshoven (1981). It is of typical Darna shape but the four
anterior and three posterior pairs of lateral tubercles are about twice as long
as the rest. The ground colour is dark grey or green mixed with black, brown or
even reddish brown. On the dorsum there is a network of grey, yellow and black
lines cut by a pale yellow or white dorsal line. There are three pairs of
subdorsal yellow patches, the central pair much larger than the other two and
invested with orange. The patches extend in a zone from just anterior to the
centre to one quarter from the posterior; sometimes these patches are more or
less fused. The anterior long processes and the first long posterior pair are
reddish brown; all other processes are pale. See below.
diducta in Peninsular Malaysia (W.J.W. Cock)
The spherical cocoon is dark reddish brown or dull brownish yellow,
enveloped in fine orange silk spun in a folded leaf.
The species reaches pest proportions on Cocos and Metroxylon but
also attacks other palms including Elaeis and Pinanga. It is also
recorded as feeding on Musa (Musaceae), Carica (Caricaceae), Annona
(Annonaceae), Theobroma (Sterculiaceae), Nephelium (Sapindaceae),
Eugenia (Myrtaceae) and Michelia (Magnoliaceae, but ?Barringtonia
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