Tahitian chestnut fruit borer.
Pacific Pests, Pathogens & Weeds
Tahitian chestnut moth (359)
Photo 1. Fruit of Tahitian chestnut, Inocarpus fagiferus, with holes bored by the larvae of Cryptophlebia pallimfimbriata.
Photo 2. Larva of Cryptophlebia pallimfimbriata tunnelling into a Tahitian chestnut fruit, Inocarpus fagiferus.
Photo 3. Larva of Cryptophlebia pallimfimbriata, tunnelling in a fruit of Tahitian chestnut, Inocarpus fagiferus.
Cryptophlebia pallifimbriana. It is a moth of the Tortricidae.
Asia, Africa, Oceania. It is recorded from Australia (Queensland), Cook Islands, Fiji, French Polynesia, and Vanuatu.
Tahitian chestnut, Inocarpus fagiferus (it is called ivi in Fiji). Other hosts are pods of Bauhinia, and Acacia, and avocado.
The larvae do the damage by boring into the fruits of Inocarpus while still on the tree, and make them unfit for eating (Photo 1). Infestation is often obvious with holes in the fruit and dark pellets of excreta protruding through the tunnel openings.
The larvae are about 15 mm long when mature, with light grey bodies and eight dark brown spots on each segment (Photos 2&3). The head and the plate covering the first segment behind the head are brown. The pupae are about the same length, brown with a row of stout spines on the top surface. They develop inside the fruit.
The adult moth is about 12 mm long, brown, with a yellowish patch at the tip of the forewing, surrounded by a curved dark brown line (Photos 4&5).
Swaine (1971)1 records this as a serious pest of ivi fruits in Fiji. There, and in many other Pacific island countries the cooked seed kernels are eaten for their high protein and carbohydrate. However, infestations are unlikely to be important as the fruit has declined in popularity. Previously, it filled a gap ('time-hungry') between harvests of major food crop staples. Today, with a monetary economy operating is most countries, collecting fruit from the wild has given way to purchasing food stuffs from stores.
Look for fruit with holes in them, split them open to see the tunnels and find the life stages of the moth. In particular, look for light grey larvae with distinctive eight spots on each segment.
None have been reported.
Ideally, infested fruit should be removed as soon as they fall, but this is unlikely to make a difference as the trees grow wild.
Not an appropriate control measure. The trees are large and wild, and the larvae are protected inside the fruit.
AUTHOR Grahame Jackson & Mani Mua
1Information from Swaine G (1971) Agricultural Zoology in Fiji. Her Majesty's Stationery Office. London; and from Cryptophlebia pallifimbriana. Wikipedia. https://en.wikipedia.org/wiki/Cryptophlebia_pallifimbriana). Photos 3&4 Gerald McCormack, Cook Islands Biodiversity & Natural Heritage. (http://cookislands.bishopmuseum.org).
Produced with support from the Australian Centre for International Agricultural Research under project HORT/2016/185: Responding to emerging pest and disease threats to horticulture in the Pacific islands, implemented by the University of Queensland and the Secretariat of the Pacific Community.