370 A. D. N. T. Kumara et al.
vae in tunnels might spread the pest to new areas
(Bedford 1980 ).
Bioecology
Female beetles lay eggs in rotting vegetation, es-
pecially in the trunks of rotting palms. The lar-
vae bore and damage in the tunnel constructed
by feces and silk among the spikes of flowers.
The life cycle lasts from 4 to 9 months allowing
more than one generation/year (Chen 1988 ). The
beetle breeds in dead standing coconut palms that
were killed by pest, disease, lightning, decay-
ing organic materials like compost and sawdust
heaps. Floating logs containing larvae in tun-
nels might spread the pest to new areas (Bedford
1980 ; Howard et al. 2001 cited Gressitt 1957 ).
The female lays around 70–140 eggs on the or-
ganic substrate; after hatching between 11 and
20 days the emerged larvae remain and feed on
the organic matter around 80–130 days. Pupa-
tion takes place in the breeding site, and organic
matter cocoon made around the pupae and adult
emergence occur after 14–30 days. The life cycle
is completed within nearly 9 months and adult
longevity about 4–6 months (Fig. 5 ) (Suwanda-
rathne, pers. comm.).
The adult beetle bores into the soft tissue of
the bud by cutting and chewing the tender un-
opened leaves and inflorescences. In the process,
the leaves and inflorescences are severely dam-
aged. The affected leaves, on the emergence,
will give a characteristic fan-like appearance
where the leaflets are cut off in the same place
on both sides of the leaf stalk. When the attack
is on the unopened spathe, the inflorescence gets
destroyed. Sometimes the beetles have also been
found boring into the soft tissues of the tender
nuts. Though death is not common in the grown-
up trees, the beetle may cause death of the young
palms by boring into the growing point and de-
stroying it, and repeated attacks may cause death
(Thampan 1975 ). In oil palm, the RB bores into
the base of the cluster of spears, causing wedge-
shaped cuts in the unfolded fronds. In younger
palms, the effect of damage can be much more
severe (Wood 1968 ). Attack by adults may re-
duce yield and kill seedlings. They may provide
entry points for lethal secondary attacks by RPW
or pathogens (Bedford 1980 ).(JJV
3XSD/DUYD$GXOWFig. 5 Life cycle of the RB