The galip weevil (Ectatorhinus magicus) ecology and life cycle

Authors

DOI:

https://doi.org/10.67387/pngjaff.v56i1.1967

Keywords:

Galip nut, East New Britain, tree architecture, weevil, vertical distribution

Abstract

The Galip Weevil (Ectatorhinus magicus) is the main pest of the Galip Nut (Canarium indicum). The adult is free-living but its larva bores tunnels in galip trees causing severe damage to the improved, elite trees in plantations and smallholder blocks in East New Britain and New Ireland Provinces. The life cycle and ecology of the weevil were studied under field and laboratory conditions using a simple cost-effective rearing technique during 2022-2023.

Larvae were reared using 25 cm cut host branches as food substrate. We found that the Galip Weevil has a complete life cycle with four larval stages. The complete cycle takes about 100 days. The cycle from egg to pupa took place inside the galip tunnels. This makes it impossible to immediately develop management strategies to control the pest. We currently recommend hand collection of the adult weevils, severing off their heads, burning them on a fire and keeping the galip blocks clean and tidy.

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Published

16-06-2026